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#59505 From: "dons3148" <dons3148@...>
Date: Sun Jun 17, 2012 11:14 am
Subject: Re: Bonobo Genome Completed
dons3148
Send Email Send Email
 
--- In AAT@yahoogroups.com, "Rob Dudman" <ausell@...> wrote:



Hello Rob...



> Hello Bill..........
>
> >
> Curiously Mans closest living "relative" is apparently the Bonobo, not the
> more aggressive brutal chimpanzee...
> >
>
> I agree that this would be a curious situation........but I'd suggest that
> the research doesn't really go so far as to say that bonobos are a closer
> relative than common chimps:


:)   o.k.



> From the Science News article........
>
> 'Despite the fact that on average the genomes of bonobos and chimpanzees are
> equally distant from human, analysis of the genome sequence of the bonobo
> revealed that for some particular parts of the genome, humans are closer to
> bonobos than to chimpanzees, while in other regions the human genome is
> closer to chimpanzees.'
>
> It seems from this that 'on average' bonobos and common chimps are
> genetically equidistant from us. If the bonobo/chimp LCA split with the
> formation of the Congo River c. 1.5 - 2 Mya, which is of course at least 2-3
> My after the H/P divergence, then given the similarity of habitat north and
> south of the river we can expect them to have remained more or less
> equidistant from us on average.



Perhaps, though they do go on to suggest also that the similarities
in certain regions of the genome could be behind behavioural
differences in bonobos, chimpanzees and humans…  which in a nutshell
could be interpreted as saying bonobos represent the best, the
chimpanzee the worst aspects of hominid behaviour...

[quote]
"Despite the fact that on average the genomes of bonobos and
chimpanzees are equally distant from human, analysis of the
genome sequence of the bonobo revealed that for some particular
parts of the genome, humans are closer to bonobos than to
chimpanzees, while in other regions the human genome is closer
to chimpanzees. Further research will determine whether these
regions contribute in any way to the behavioural differences
and similarities between humans, chimpanzees, and bonobos."

_______________


I would say the differences between bonobos and their more
aggressive kin are likely to be largely  behavioral, whether
they are the result of genetic or an adaptive differences
(apparently the bonobos did not face much if any competition
from the gorilla south of the Congo river) is an
another question.




>
> Of interest is a paper I found while reading around the topic during a
> recent conversation with Elaine...............
>
> 'Analysis of Chimpanzee History Based on Genome Sequence
> Alignments'
> By Caswell, J.L., et al.
>
> 'We show that bonobos and common chimpanzees were separated ~1,290,000 years
> ago, western and other common chimpanzees ~510,000 years ago, and eastern
> and central chimpanzees at least 50,000 years ago. We infer that the central
> chimpanzee population size increased by at least a factor of 4 since its
> separation from western chimpanzees, while the western chimpanzee effective
> population size decreased. Surprisingly, in about one percent of the genome,
> the genetic relationships between humans, chimpanzees, and bonobos appear to
> be different from the species relationships.'
>
> http://tinyurl.com/7yhzdnv
> ____________
>
> If bonobos and common chimps were genetically separated at c.1.3 Mya, then
> the time-lag for the accumulated adaptations that
> resulted in this sub-speciation (given an identical rainforest habitat),
> would make their geographic separation more or less contemporary with the
> formation of the Congo River.
>



Thanks for the link...

With the presence of the a'piths in eastern Africa (probably related
to Man) and in southern Africa (unrelated to Man) millions of years
ago, I have tended to presume that the west Africa chimpanzee or its
ancestor was the origin of today's various chimpanzee (sub)species…
spreading into central Africa and subsequently east Africa when the
southern a'piths became extinct.

This illustration of the current geographical distribution of bonobos
and various chimpanzee species is from the paper in Nature:

http://www.nature.com/nature/journal/vaop/ncurrent/fig_tab/nature11128_F1.html

________________________



Note the Congo river acts to separate the bonobos from the eastern
chimpanzee as claimed, but another river to the north splits the
territory of the eastern chimpanzee in two, yet does seem to be a
barrier for the eastern chimpanzee on either side of the river.
I would say the main role of the Congo river as such seems to have
been to keep the gorilla to the north, while allowing the bonobos
south of the river to adapt without competition from the gorilla.

Nature link:
The bonobo genome compared with the chimpanzee and human genomes
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11128.html
________________________________



> It seems to me that if we're going to use this research to shed some light
> on our own evolutionary path, then we need to ask if the information can
> offer clues as to the geographic location of the ancestral chimp population.
> When we have an idea of where the ancestral chimps emerged, we can surely
> take it for granted that the geographic location of the H/P LCA just prior
> to the divergence was within plausible walking distance (whatever distance
> that might have been for the H/P LCA and it surely wasn't very far if they
> were to remain viable candidates for adapting to rainforest
> knuckle-walking).
>


The territory of central chimpanzee today is approximately directly
south of Chad, while that of the west African chimpanzee is to the
west or south-west…  As to how far the ancestor of the extant
chimpanzee would have had to move in terms of distance, it may not
have been problematic … as it could have depended on how fast the
rainforest retreated southwards or broke-up in the face of climate
change over north-Africa (if it was a gradual retreat, possibly the
ancestor of the extant chimpanzee simply followed it southwards
over generations).



> Eastern and central chimps separated only c. 50 Kya, but this result begs
> the question of where those Kenyan fossil chimp teeth came from (there were
> three reported by Jabonski et al. and dated to c. 500 Kya); those teeth are
> contemporary with the estimated time for the split between western and
> central chimpanzees and this requires explanation. While the earlier
> central/western divergence c. 500 Kya doesn't definitively identify either
> central or western Africa as the ancestral location, it does add some weight
> to the proposition that the ancestral location was not eastern Africa.
>


The Kenyan fossils, could be those of an ancestor of the extant
chimpanzee who strayed too far east (like those remains of a'pith
in Chad (who is said to have strayed too far west of the Rift!)...



> What the results do show is that since the central/west divergence the
> western population has declined while the central population has
> significantly increased. Given that the rainforest habitat was then as
> identical east/west as it was north/south in the case of the later bonobo
> emergence, it makes sense to ask what sort of circumstances could result in
> this quite dramatic demographic difference?
>
> Maybe a western population ravaged by a disease that didn't reach the
> outliers, who then went on to thrive and spread into central Africa? OTOH,
> those Kenyan teeth imply an ancestral population that had spread throughout
> the entire rainforest and only the western inhabitants were reduced by a
> disease c. 500 Kya that left survivors identifiably different from those who
> succumbed?
>
> In all I think this genetic evidence lends support to the proposition that
> the ancestral chimp population was central African. When they found success
> in one part of tropical rainforest they were pretty well suited to any part
> of it and from a central location they could spread south to become bonobos
> and east-west to eventually become western and eastern common chimps.
>


I would tend to favour a chimpanzee ancestor spread from the west, as
eastern and southern Africa would likely have been home to the a'piths,
and central Africa home to whatever proceeded the extant gorilla




> (Another puzzle that intrigues me is why the gorilla, with about 8 million
> years to spread throughout a uniform rainforest habitat, does not live south
> of the Congo River and AFAIK, they never have.......chimps obviously spread
> there, so why not the gorilla with so much more time at their disposal? Then
> maybe they did and the southerners have since been exterminated by H.ss.
> Given the size of the rainforest, is that at all feasible prior to
> firearms?)
>


Need not have been H.ss, the territory might have already been
occupied by the southern a'piths, some of whom are said to have
been pretty robust. But, on balance as the bonobos south of the
Congo river seemed not to have encountered or competed with the
gorilla, it looks like the gorilla did not stray south of the
Congo river.

Gorilla was first observed on the west coast by mariners of the
ancient world (Carthaginians) who sailed down the west African
a few thousand years ago, they seemingly mistook Gorilla for a
tribe of hairy women… hence the name Gorilla!

(Guess those Carthaginians, had been at sea too long!)



> My belated apologies for a sudden exit from our previous conversation - I
> had to deal with a threat to the long-term health of my spine. All's well
> that ends well and I'm back running and back on the tennis court.
>
> Rob.


Great to hear all's well on the health front, Rob...
long may it continue.


With regards to our previous conversation Rob, you might be interested
to know Ajit Vakari and his colleagues have recently come out with a
new paper, it appears to detail a more recent inactivation in the
human lineage to enhance immunity from pathogens… pathogens that
appear to have targeted the newborn.

PNAS
Specific inactivation of two immunomodulatory SIGLEC genes
during human evolution

http://www.pnas.org/content/early/2012/05/30/1119459109


This account in Science Daily is a little confusing... as the abstract
of the paper in question appears to say it occurred in common ancestor
of H.ss, the Neanderthals and the Denisovans... while this article
places it only a few hundred thousand years ago.


How Infectious Disease May Have Shaped Human Origins

[Quote]
"In a paper published in the June 4, 2012 online Early Edition
of The Proceedings of the National Academy of Sciences, an
international team of researchers, led by scientists at the
University of California, San Diego School of Medicine, suggest
that inactivation of two specific genes related to the immune
system may have conferred selected ancestors of modern humans
with improved protection from some pathogenic bacterial strains,
such as Escherichia coli K1 and Group B Streptococci, the leading
causes of sepsis and meningitis in human fetuses, newborns
and infants.

http://www.sciencedaily.com/releases/2012/06/120604155554.htm

________________________________



Bill







> From: AAT@yahoogroups.com [mailto:AAT@yahoogroups.com] On Behalf Of dons3148
> Sent: Thursday, 14 June 2012 9:17 PM
> To: AAT@yahoogroups.com
> Subject: [AAT] Bonobo Genome Completed
>
>
> In a project led by the Max Planck Institute for Evolutionary
> Anthropology in Leipzig, an international team of scientists
> has completed the sequencing and analysis of the genome of the
> last great ape, the bonobo. Bonobos, which together with
> chimpanzees are the closest living relatives of humans, are
> known for their peaceful, playful and sexual behaviour that
> contrasts with the more aggressive behaviour
> of chimpanzees.
>
> Bonobo Genome Completed: The Final Great Ape to Be Sequenced
> http://www.sciencedaily.com/releases/2012/06/120613133144.htm
>
> _________________________________
>
> Curiously Mans closest living "relative" is apparently
> the Bonobo, not the more aggressive brutal chimpanzee...
>
> Neither of course is as close to Man as were the
> Neanderthals, where the difference was less than
> one percent (chimpanzees, differ by nearly 6%).
>
> [Quote]
> "A lot more genes may separate humans from their chimp relatives
> than earlier studies let on. Researchers studying changes in the
> number of copies of genes in the two species found that their mix
> of genes is only 94 percent identical. The 6 percent difference
> is considerably larger than the commonly cited figure
> of 1.5 percent."
>
> Scientific American:
>
> Human-Chimp Gene Gap Widens from Tally of Duplicate Genes
> There's a bigger genetic jump between humans and chimps than previously
> believed
>
> http://www.scientificamerican.com/article.cfm?id=human-chimp-gene-gap-wide
>
> __________________________________
>
>
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2012.0.2177 / Virus Database: 2411/5045 - Release Date: 06/04/12
> Internal Virus Database is out of date.
>
>
> [Non-text portions of this message have been removed]
>

#59506 From: Marc Verhaegen <m_verhaegen@...>
Date: Sun Jun 17, 2012 1:25 pm
Subject: Re: World's oldest cave art Neanderthal.
aquape
Send Email Send Email
 
U-Series Dating of Paleolithic Art in 11 Caves in Spain
AWG Pike cs 2012 Science 336:1409-13 doi 10.1126/science.1219957

... We present U-series disequilibrium dates of calcite deposits over- or
underlying art found in 11 caves (incl.Altamira, El Castillo & Tito
Bustillo):
the tradition of decorating caves extends back at least to the Early
Aurignacian period, with minimum ages of
- 40.8 ka for a red disk,
- 37.3 ka for a hand stencil &
- 35.6 ka for a claviform-like symbol.
These minimum ages reveal either that
- cave art was a part of the cultural repertoire of the first anatomically
modern humans in Europe or
- perhaps Neandertals also engaged in painting caves.

________



John Hellstrom 2012 Science 336:1387-8
Absolute Dating of Cave Art
Fig.  U-Th sampling of calcite overgrowths. Since U-Th dating was first
introduced in the 1960s, sample size requirements have fallen continually.
Large jumps in efficiency occurred with the introduction of mass
spectrometric analysis & advances in mass spectrometric technology, and
can now often lead to sample sizes of <10 mg or 4 mm3. As shown by Pike
cs, a 1 mm-thick speleothem film overlying a cave art panel can now be
dated by removing a few mm2 of overgrowth, minimizing impact on the
artwork.
Use of uranium-thorium dating shows that cave art in Spain is older than
expected.
... despite great advances in dating technologies, it remains extremely
difficult to determine the age of a thin layer of pigment on a cave or
rock shelter wall.
Researchers are often limited to reconstructing relative chronology by
comparing drawing styles and, where available, creating sometimes tenuous
links to other dated human remains or artifacts.
Mass-spectrometric radio-C dating has arguably been the most successful
technique for dating cave art, in the rare cases where it is possible to
directly date charcoal or other
pigments containing C.
Pike cs p.1409 report an ambitious study of paleolithic cave art sites
from Spain, in which they have applied the previously under used U-Th
dating method.
U-Th dating measures the ingrowth of Th*230 in a geological or biogenic
material, through decay of U incorporated within it at its time of
formation.
When it was first applied almost 50 years ago, this technique required
samples of 100 g or more in the case of cave formations such as those now
dated by Pike cs.
In 1987, Edwards cs showed that U-Th dating could be conducted as long as
large amounts of material were required for dating, its sampling could
only be condoned in very rare circumstances. The greatly reduced sample
size required for analysis allows subtle removal of small volumes of
speleothem directly ass.x cave art, from which precise absolute ages may
be determined.
Coatings of speleothem calcite do not directly date the cave art itself,
but give robust & reliable determinations of the minimum age for the
underlying art.
Any one calcite overgrowth has a rel.low probability of approaching the
age of the underlying art.
Studies of overlying calcite layers that consider a small number of
examples of cave art in isolation may therefore return ages that do not
advance understanding of the age of that art.
By undertaking a broad regional study of many examples of cave art, Pike
cs have transcended this problem.
The scope of their study has allowed them to unambiguously identify a
number of examples that challenge & overturn the previous understanding of
that art's origin.
In particular, 3 of the 50 examples dated show art to have been created in
Spain at around (or indeed possibly before) the time of the arrival of
modern humans, bringing current ideas of the prehistory of human art in
S-Europe into question.
U-Th dating, particularly of speleothems, has mostly been used to
reconstruct climatic change over the past several hundreds of thousands of
years.
The techniques developed for this field now allow archaeological
applications to be revisited.
Human remains, artifacts & other evidence of habitation are sometimes
coated with CaCO3 coatings, and may thus be dated in the same way as the
cave art of Pike's study.
Sample material can be collected using micro-machining strategies
developed for high-resolution climate change chronologies, such that
growth intervals & durations may be determined, even within a single thin
film of carbonate.
Other applications include the dating of cave sediments, using fragile
incorporated fragments of soda straw stalactites.
All geo-chronological technologies available for dating prehistorical
remains have improved greatly over recent decades ...
U-Th dating has become >10,000 times more efficient since its invention,
and in the case of the technique used by Pike cs, there is little room for
further spectacular gains.
Now allowing cave art & other human artifacts found in caves to be dated
based on a few mg of speleothem calcite, the U-Th technique can be
considered mature enough for widespread use in this field.
Pike's findings push the earliest evidence of cave art in Europe back by
several 1000 years to at least 40.8 ka: Was such art the exclusive domain
of modern humans?
news.nationalgeographic.com/news/2012/06/120614-neanderthal-cave-paintings-
spain-science-pike/
<http://news.nationalgeographic.com/news/2012/06/120614-neanderthal-cave-pa
intings-spain-science-pike/>

______


IOW, there's no evidence Hn made cave-art. --marc

#59507 From: "dons3148" <dons3148@...>
Date: Mon Jun 18, 2012 12:21 pm
Subject: A Warmer, Drier Africa 20 Mya?
dons3148
Send Email Send Email
 
Apparently it was warm enough 15 to 20 million years ago for trees to
grow on the coasts of Antarctica... if it was this warm at the poles,
could this have resulted in more arid climate in Africa...


[ABSTRACT]
"From 20 to 15 million years (Myr) ago, a period of global warmth
reversed the previous ice growth on Antarctica, leading to the
retreat of the West Antarctic Ice Sheet and the contraction of the
East Antarctic Ice Sheet1, 2. Pollen recovered from the Antarctic
shelf indicates the presence of substantial vegetation on the margins
of Antarctica 15.7 Myr ago3. However, the hydrologic regime that
supported this vegetation is unclear. Here we combine leaf-wax
hydrogen isotopes and pollen assemblages from Ross Sea sediments
with model simulations to reconstruct vegetation, precipitation and
temperature in Antarctica during the middle Miocene. Average leaf-wax
stable hydrogen isotope (&D) values from 20 to 15.5 Myr ago
translate to average -D values of 50‰ for precipitation at
the margins of Antarctica, higher than modern values. We find that
vegetation persisted from 20 to 15.5 Myr ago, with peak expansions
16.4 and 15.7 Myr ago coinciding with peak global warmth and
vegetation growth. Our model experiments are consistent with a
local moisture source in the Southern Ocean6. Combining proxy
measurements with climate simulations, we conclude that summer
temperatures were about 11°C warmer than today, and that there
was a substantial increase in moisture delivery to the Antarctic
coast."


Hydrologic cycling over Antarctica during the middle Miocene warming
http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1498.html

_____________________________

#59508 From: Marc Verhaegen <m_verhaegen@...>
Date: Mon Jun 18, 2012 6:43 pm
Subject: Re: A Warmer, Drier Africa 20 Mya?
aquape
Send Email Send Email
 
Thanks a lot.  17 Ma was when we find the earliest great hominoid in
Europe (google Engelswies hominoids) - due to the hot climate?
It's found in a lake-side (swamp / sea-side? --mv) landscape with
reed-beds & palm-trees.

The Oldest Eurasian Hominoids Lived in Swabia.
Africa is regarded as the centre for the evolution of humans & their
precursors.
Yet long before modern humans left Africa some 125 ka, their antecedents
migrated from Africa to Eurasia many times, as is documented by fossils.
How often, when & why hominoids went "out of Africa" is still a hotly
debated field of intense research.
Possibly, the first wave of emigration occurred at 17 Ma, as documented by
finds in the Swabian N-Alpine foreland basin, SW of Sigmaringen.
Researchers from Tübingen cs (JHE 2011) successfully pinpointed the age of
a molar tooth at 17–17.1 Ma ...
It is thus the oldest known Eurasian hominoid found to date.
The owner of the tooth once inhabited a lake-side landscape with
subtropical vegetation in a warm-humid climatic zone.
Today, there is an abandoned quarry at the locality known among
palaeontologists for its fossiliferous layers.
... the find itself dates to June 24th 1973 ... Only in 2001 was the molar
taken under scrutiny, and determined as a hominoid fossil ...
... the mean yearly Tp was c 20°C in the area of what is now S-Germany,
some 11°C above today's conditions. Winters were frost-free.
There was a swamp to the S of the lake, full of reed-beds & a coast-line
of trees, palm trees (amongst them the climbing rattan palms), lianas,
ferns & grasses.
To the N was a slope covered by an evergreen forest. This vegetation is
unique in the circum-Alpine area.
"The chronologic relationships support the idea that the Engelswies
hominoid was a descendent of Early Miocene Afro-Arabian afropithecins."
This find is thus the earliest known trace of hominoids which immigrated
to Eurasia from Africa ...
Böhme M cs 2011 JHE doi 10.1016/j.jhevol.2011.04.012
Bio-magnetostratigraphy and environment of the oldest Eurasian hominoid
from the Early Miocene of Engelswies (Germany)









Apparently it was warm enough 15 to 20 million years ago for trees to
grow on the coasts of Antarctica... if it was this warm at the poles,
could this have resulted in more arid climate in Africa...

[ABSTRACT]
"From 20 to 15 million years (Myr) ago, a period of global warmth
reversed the previous ice growth on Antarctica, leading to the
retreat of the West Antarctic Ice Sheet and the contraction of the
East Antarctic Ice Sheet1, 2. Pollen recovered from the Antarctic
shelf indicates the presence of substantial vegetation on the margins
of Antarctica 15.7 Myr ago3. However, the hydrologic regime that
supported this vegetation is unclear. Here we combine leaf-wax
hydrogen isotopes and pollen assemblages from Ross Sea sediments
with model simulations to reconstruct vegetation, precipitation and
temperature in Antarctica during the middle Miocene. Average leaf-wax
stable hydrogen isotope (&D) values from 20 to 15.5 Myr ago
translate to average -D values of 50‰ for precipitation at
the margins of Antarctica, higher than modern values. We find that
vegetation persisted from 20 to 15.5 Myr ago, with peak expansions
16.4 and 15.7 Myr ago coinciding with peak global warmth and
vegetation growth. Our model experiments are consistent with a
local moisture source in the Southern Ocean6. Combining proxy
measurements with climate simulations, we conclude that summer
temperatures were about 11°C warmer than today, and that there
was a substantial increase in moisture delivery to the Antarctic
coast."

Hydrologic cycling over Antarctica during the middle Miocene warming
http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1498.html

#59509 From: "dons3148" <dons3148@...>
Date: Tue Jun 19, 2012 10:57 am
Subject: Re: A Warmer, Drier Africa 20 Mya?
dons3148
Send Email Send Email
 
--- In AAT@yahoogroups.com, Marc Verhaegen <m_verhaegen@...> wrote:
>
> Thanks a lot.  17 Ma was when we find the earliest great hominoid in
> Europe (google Engelswies hominoids) - due to the hot climate?
> It's found in a lake-side (swamp / sea-side? --mv) landscape with
> reed-beds & palm-trees.
>
> The Oldest Eurasian Hominoids Lived in Swabia.


Possible as some twenty million years ago a large chunk of central and southern
Europe were likely to have been under the waters of the Tethys. (sea levels
would have higher 20 Mya, with less water locked up as ice).

Closure of the Tethys
http://www.uwgb.edu/dutchs/platetec/closteth.htm

Note on the first map - the sea is estimated have reached as far north as
southern Germany/Swabia 20 Mya...



> Africa is regarded as the centre for the evolution of humans & their
> precursors.
> Yet long before modern humans left Africa some 125 ka, their antecedents
> migrated from Africa to Eurasia many times, as is documented by fossils.
> How often, when & why hominoids went "out of Africa" is still a hotly
> debated field of intense research.
> Possibly, the first wave of emigration occurred at 17 Ma, as documented by
> finds in the Swabian N-Alpine foreland basin, SW of Sigmaringen.
> Researchers from Tübingen cs (JHE 2011) successfully pinpointed the age of
> a molar tooth at 17â€"17.1 Ma ...



There possibly was no land bridge between the two continents before 17/19
million years ago (Arabia the bit that is broke of Africa, when Africa hit
Europe, probably provided the first land link when the eastern end of the
Tethys was finally closed by Africa moving northwards).

Sicily might provide an older 'European' ape fossil, as Sicily was once a
bit of Africa. (Sicily could have provided a land bridge to Europe when
sea levels were low).

[quote]
"Was Sicily ever attached to Africa or to mainland Italy? It almost certainly
was, but even today Sicily is only 3 kilometers from Calabria at the narrows
of the Strait of Messina, and just 160 kilometers from the African coast.
Sicily's most southern point, near Ispica, is farther south than parts of the
Tunisian coast, and while much of Sicily's flora and fauna are colsely related
to those of peninsular Italy others show a closer affinity with Africa.
Prehistoric fossils of large mammals discovered in caverns and during
excavations around the island suggest that a land bridge existed in the
remotest times."

Sicily: An Island Poised Between Europe, Africa and Asia




> It is thus the oldest known Eurasian hominoid found to date.
> The owner of the tooth once inhabited a lake-side landscape with
> subtropical vegetation in a warm-humid climatic zone.
> Today, there is an abandoned quarry at the locality known among
> palaeontologists for its fossiliferous layers.
> ... the find itself dates to June 24th 1973 ... Only in 2001 was the molar
> taken under scrutiny, and determined as a hominoid fossil ...
> ... the mean yearly Tp was c 20°C in the area of what is now S-Germany,
> some 11°C above today's conditions. Winters were frost-free.
> There was a swamp to the S of the lake, full of reed-beds & a coast-line
> of trees, palm trees (amongst them the climbing rattan palms), lianas,
> ferns & grasses.
> To the N was a slope covered by an evergreen forest. This vegetation is
> unique in the circum-Alpine area.
> "The chronologic relationships support the idea that the Engelswies
> hominoid was a descendent of Early Miocene Afro-Arabian afropithecins."
> This find is thus the earliest known trace of hominoids which immigrated
> to Eurasia from Africa ...
> Böhme M cs 2011 JHE doi 10.1016/j.jhevol.2011.04.012
> Bio-magnetostratigraphy and environment of the oldest Eurasian hominoid
> from the Early Miocene of Engelswies (Germany)
>



A more interesting, an more important ancestor 20 (20.6) Mya would have
been Moroto (Morotopithecus) in eastern Africa.  That had a orthograde
trunk posture (vertical posture).


_____________________________








>
> Apparently it was warm enough 15 to 20 million years ago for trees to
> grow on the coasts of Antarctica... if it was this warm at the poles,
> could this have resulted in more arid climate in Africa...
>
> [ABSTRACT]
> "From 20 to 15 million years (Myr) ago, a period of global warmth
> reversed the previous ice growth on Antarctica, leading to the
> retreat of the West Antarctic Ice Sheet and the contraction of the
> East Antarctic Ice Sheet1, 2. Pollen recovered from the Antarctic
> shelf indicates the presence of substantial vegetation on the margins
> of Antarctica 15.7 Myr ago3. However, the hydrologic regime that
> supported this vegetation is unclear. Here we combine leaf-wax
> hydrogen isotopes and pollen assemblages from Ross Sea sediments
> with model simulations to reconstruct vegetation, precipitation and
> temperature in Antarctica during the middle Miocene. Average leaf-wax
> stable hydrogen isotope (&D) values from 20 to 15.5 Myr ago
> translate to average -D values of 50‰ for precipitation at
> the margins of Antarctica, higher than modern values. We find that
> vegetation persisted from 20 to 15.5 Myr ago, with peak expansions
> 16.4 and 15.7 Myr ago coinciding with peak global warmth and
> vegetation growth. Our model experiments are consistent with a
> local moisture source in the Southern Ocean6. Combining proxy
> measurements with climate simulations, we conclude that summer
> temperatures were about 11°C warmer than today, and that there
> was a substantial increase in moisture delivery to the Antarctic
> coast."
>
> Hydrologic cycling over Antarctica during the middle Miocene warming
> http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1498.html
>

#59510 From: "Rob Dudman" <ausell@...>
Date: Tue Jun 19, 2012 11:19 am
Subject: RE: Re: Bonobo Genome Completed
rob_dudman
Send Email Send Email
 
Hello Bill..........

>
> I would say the differences between bonobos and their more      >
aggressive kin are likely to be largely behavioral, whether they > are the
result of genetic or an adaptive differences (apparently   > the bonobos did
not face much if any competition from the        > gorilla south of the
Congo river) is an another question.             >
and............
>
> Note the Congo river acts to separate the bonobos from the        >
eastern chimpanzee as claimed, but another river to the north    > splits
the territory of the eastern chimpanzee in two, yet does    > seem to be a
barrier for the eastern chimpanzee on either side of > the river. I would
say the main role of the Congo river as such   > seems to have been to keep
the gorilla to the north, while           > allowing the bonobos south of
the river to adapt without             > competition from the gorilla.
>

As I understand it, the general idea seems to go something like this: the
formation of the Congo River permanently separated the chimp population
south of the river from those north of the river. The southern population
did not have to compete with gorillas for resources and the resultant plenty
then led to less intraspecific aggressive behaviour, which in turn led to a
neotenous trend in adaptation.

It's neat, but surely an early and predictable consequence of such
uncontested resources would be a rise in population density and, by now, a
spread to all parts of the rainforest south of the river and this is not the
case. More to the point, north of the river there is little competition for
resources between chimps and gorillas....... they specialize in different
foods and the huge size of the rainforest habitat allows the two species to
be widely separated from each other and therefore not troubled by
competition for the few resources shared by the two species. The idea that a
lack of competition from gorillas in a vastness like the African rainforest
would be the trigger for the social changes so characteristic of the bonobo,
is simply not at all compelling IMO.

(Given the numbers and distribution of the two species in the vast
rainforest north of the Congo River, it could well be the case that all but
a miniscule percentage of the chimps who have ever lived never saw or even
smelled a gorilla and vice-versa. Come to think of it, by the age of fifteen
I'd probably seen more gorillas than most chimps who have ever lived and I
grew up in Devonshire!)

The three characteristics of bonobo life that clearly differentiate them
from the common chimp are their comparative lack of intra- specific
aggression, their use of simulated copulation to ease social tension and
their enjoyment of play well into adulthood.
Bearing in mind that human toddlers will massage their genital area to ease
anxiety, the neotenous trend that also extended playfulness in bonobos could
well have extended the use of genital massage into a broader social setting.



But the comparative lack of intraspecific aggression is not only the
characteristic which can most readily 'set the stage' for the other two,
it's also the most likely to have been genetically determined. One
possibility would be that the group first isolated south of the river
happened to lack a chimp version of the MAOA-L variation found in a small
percentage of humans (commonly called 'the warrior gene'). Now that the
bonobo genome is complete someone might think to look.

>
> With the presence of the a'piths in eastern Africa (probably       >
related to Man) and in southern Africa (unrelated to Man)          >
millions of years ago, I have tended to presume that the west     > Africa
chimpanzee or its ancestor was the origin of today's        > various
chimpanzee (sub)species...spreading into central Africa > and subsequently
east Africa when the southern a'piths became > extinct.
>

Until I can find an explanation for our lack of those RV markers that
doesn't involve special-pleading, then I'm forced to the null that the
A'piths are not more closely related to us than chimps and in fact I still
have the opinion that the most likely relational distance is probably the
same in both cases......ie., there was an A/H/P LCA; with neither A. nor H.
finding refuge in the rainforest after the divergence.

>
> The territory of central chimpanzee today is approximately        >
directly south of Chad, while that of the west African                  >
chimpanzee is to the west or south-west... As to how far the      > ancestor
of the extant chimpanzee would have had to move in    > terms of distance,
it may not have been problematic ... as it       > could have depended on
how fast the rainforest retreated            > southwards or broke-up in the
face of climate change over         > north-Africa (if it was a gradual
retreat, possibly the ancestor of > the extant chimpanzee simply followed it
southwards over          > generations).
>

I understand that the Megalake was so big that it reached south to the
rainforest and while the climatic consequences of the MSC would have been
felt that far south (the evaporating Med was being dumped somewhere and
probably expanded the northern limits of the rainforest), I think it would
have been the draining of the lake that caused the (A)/H/P LCA that had
previously exploited the southern edges of the Megalake to then move further
south and into the rainforest to become the ancestral chimps. Central and/or
western, I don't think that they had very far to go and given what a rapidly
draining lake leaves behind, I think they probably did it quickly.


>
> The Kenyan fossils, could be those of an ancestor of the extant
> chimpanzee who strayed too far east (like those remains of        > a'pith
in Chad (who is said to have strayed too far west of the     > Rift!)...
>

If I may misquote that great paleoanthropologist Gerry Lee Lewis: 'There's a
whole lotta strayin' goin' on.'

:-)

What Abel does show is that from a hominid point of view there was a viable
'ecological corridor' between Chad and East Africa c. 3.5 Mya. The
affinities between A.bahrelghazali and A.afarensis  indicate that spread
over those many kms and many generations the central African arafensis had
changed enough to become a subspecies. One of the safest predictions in
paleoanthropology surely has to be that there are more A'pith fossils
waiting to be found between the Abel site and the Lucy site.

Of interest..........

  'Two new Mio-Pliocene Chadian hominids enlighten Charles Darwin's 1871
prediction'
By Michel Brunet
<http://rstb.royalsocietypublishing.org/search?author1=Michel+Brunet&sortspe
c=date&submit=Submit> .

http://rstb.royalsocietypublishing.org/content/365/1556/3315.full
__________________

>
> Gorilla was first observed on the west coast by mariners of the
> ancient world (Carthaginians) who sailed down the west African
> a few thousand years ago, they seemingly mistook Gorilla for a
> tribe of hairy women... hence the name Gorilla!
>
> (Guess those Carthaginians, had been at sea too long!)
>

IIRC, Hanno reported that they killed and skinned three of them...... some
things don't change much.

>
> With regards to our previous conversation Rob, you might be       >
interested to know Ajit Vakari and his colleagues have recently   > come out
with a new paper, it appears to detail a more recent       > inactivation in
the human lineage to enhance immunity from       > pathogens... pathogens
that appear to have targeted the newborn.
>
> PNAS
> Specific inactivation of two immunomodulatory SIGLEC genes
> during human evolution
>
> http://www.pnas.org/content/early/2012/05/30/1119459109
>
> This account in Science Daily is a little confusing... as the            >
abstract of the paper in question appears to say it occurred in       >
common ancestor of H.ss, the Neanderthals and the Denisovans... > while this
article places it only a few hundred thousand years ago.
>
> How Infectious Disease May Have Shaped Human Origins
>
> [Quote]
> "In a paper published in the June 4, 2012 online Early Edition
> of The Proceedings of the National Academy of Sciences, an
> international team of researchers, led by scientists at the
> University of California, San Diego School of Medicine, suggest
> that inactivation of two specific genes related to the immune
> system may have conferred selected ancestors of modern humans
> with improved protection from some pathogenic bacterial strains,
> such as Escherichia coli K1 and Group B Streptococci, the leading
> causes of sepsis and meningitis in human fetuses, newborns
> and infants.
>
> http://www.sciencedaily.com/releases/2012/06/120604155554.htm
>

In the abstract they say.......

'We describe two primate Siglecs that were rendered nonfunctional by single
genetic events during hominin evolution after our common ancestor with the
chimpanzee.'

and


'Neanderthal and Denisovan genomes show human-like sequences at both loci,
corroborating estimates that the initial pseudogenization events occurred in
the common ancestral population of these hominins.'


If I sneakily change 'the common ancestral population' to 'a common
ancestral population', that's a time-window of about 5 million years! The
abstract doesn't say which sialic acid was recognized by these Siglecs, but
I'm game......I'll predict the time at c. 2.4-5 Mya and the acid was Neu5Gc.

Rob.



[Non-text portions of this message have been removed]

#59511 From: Marc Verhaegen <m_verhaegen@...>
Date: Tue Jun 19, 2012 7:26 pm
Subject: Re: Darren Naish article on AAT/Aquarboreal Theory
aquape
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>http://sciencefocus.com/feature/life/aquatic-apes

Thanks a lot, DD.
The poor man has still no idea what AAT is about. He still thinks AAT is
about apiths ("hominids").


Were we once aquatic apes?
Darren Naish examines(?? Naish lets us know his prejudices --mv) a debate
that's lasted 50 years.
In 1960, the marine biologist Sir Alister Hardy proposed that humans had
gone through an aquatic phase in their history. Hardy pointed to human
swimming abilities, hairlessness, hair tracts patterns and the presence of
subcutaneous fat in support of his idea. Hardy's hypothesis was mentioned
by Desmond Morris in his 1967 book The Naked Ape, but it was television
script-writer Elaine Morgan who made the Aquatic Ape Hypothesis (AAH)
famous thanks to her several books, especially The Aquatic Ape (published
in 1982). Morgan expanded on Hardy's idea, arguing that many additional
peculiarities of human biology and anatomy pointed to an aquatic phase in
human ancestry. A 1987 conference devoted to the AAH resulted in a
technical volume containing 22 contributions, the more scholarly of which
argued against the AAH.(the less informed, he means... --mv)
It has been argued that German anatomist Max Westenhöfer supported the AAH
in his work of the 1920s and 30s. Westenhöfer interpreted an aquatic
ancestry for humans within his "initial bipedalism" hypothesis. According
to this idea, humans are the most structurally primitive of primates and
the ancestors of all other primate groups. This work is
generally regarded as "fringe" science today.(by people like Naish... --mv)
Today, the AAH has mostly failed to win adherents and is not considered
seriously by mainstream primatologists or anthropologists.(not impossible,
but unproven --mv) There are several reasons for this. One is that the
basic arguments are erroneous. That is, the supposedly "aquatic" features
of humans are either not unique among primates, or are not like those of
aquatic mammals as the AAH argues.(nonsense, eg, all furless + fat mammals
spend a lot of time in the water --mv) Some monkeys are capable swimmers
and divers, for example.(=anti-AAT argument? :-D --mv) The "diving reflex"
is present in other primates and indeed in other mammals, the babies of
just about all mammals behave the same when placed in water, and there are
non-human primates that sweat as much as humans do. The descended human
larynx is not unique to aquatic species, nor are humans unique in their
hair tract patterns, in possessing hymens, in the position of their fat
deposits, and so on.(so? irrelevant - I never said otherwise  --mv)
Fossil evidence also fails to support the AAH.(nonsense: all archaic Homo
are found in waterside sediments, often littoral, AFAWK always next to
edible shellfish --mv) Morgan and her supporters argued against the idea
that humans owed their anatomy to a life in dry, hot grasslands, but this
is a straw-man argument since early fossil members of the human lineage
were woodland- or forest-adapted animals. Furthermore, fossil hominids
lack adaptations special to mammals that regularly swim or forage in
water.(:-D eg, pachyostosis  --mv) The supposed peculiarities of humans
are well explained by adaptation to a lifestyle where sweating,(:-DDD  the
most sweating mammals are humans & sealions on land  -mv) complex
formation of sounds in communication, and exploitation of scarce, fatty
foods were important.
Some modern supporters of the AAH argue that great apes went through an
"aquarboreal" phase in which they waded and swam in swampy forests,
feeding on molluscs and fruit. Members of the human lineage, they argue,
became bipedal in this context and remained tied to waterside resources as
coastal foragers. It is possible that at least some fossil humans
and human relatives foraged on shorelines or in mangroves, waded in
shallows, or ate aquatic foods like crabs, stranded fish and
shellfish.(the first sensible sentence... --mv)
However, there are no indications that such a lifestyle, if it existed,
left any obvious mark on human anatomy, so this watered-down idea of a
link with aquatic environments cannot be considered in the same ballpark
as the AAH.(platycephaly, platymeria, ear exostoses, pachyostosis, flaring
ilia, short tibiae, huge brain etc.etc.  --mv)
Despite a huge number of recent fossil hominid discoveries, fossil
evidence that might support the AAH has not appeared.(:-D  Homo flew to
Flores?  --mv) The evidence from primate physiology, behaviour and anatomy
also fails to support it.(ridiculous statement  --mv)
Overall, the AAH remains a historical curiosity, but not an acceptable
explanation for human evolution. It is, many argue, dead in the
water.(we're not interested in the nonsense Naish "argues"...  --mv)
Darren Naish is a palaeozoologist at the University of Southampton (a pity
for the Univ.of Southampton  --mv)

#59512 From: Marc Verhaegen <m_verhaegen@...>
Date: Tue Jun 19, 2012 8:04 pm
Subject: Archaeologist finds oldest rock art in Australia 18.6.12
aquape
Send Email Send Email
 
http://www.boston.com/news/science/articles/2012/06/18/archaeologist_fin
<http://www.boston.com/news/science/articles/2012/06/18/archaeologist_fin\>
ds_oldest_rock_art_in_australia/

Rod McGuirk

?An archaeologist says he found the oldest piece of rock art in Australia
and one of the oldest in the world:
an Aboriginal work created 28 ka in an Outback cave.

The dating of one of the thousands of images in the Northern Territory
rock shelter known as Nawarla Gabarnmang will be published in J archaeol
Sci.

#59513 From: Marc Verhaegen <m_verhaegen@...>
Date: Tue Jun 19, 2012 8:11 pm
Subject: Re: Re: A Warmer, Drier Africa 20 Mya?
aquape
Send Email Send Email
 
> Thanks a lot.  17 Ma was when we find the earliest great hominoid in
> Europe (google Engelswies hominoids) - due to the hot climate?
> It's found in a lake-side (swamp / sea-side? --mv) landscape with
> reed-beds & palm-trees.

> The Oldest Eurasian Hominoids Lived in Swabia.

Possible as some twenty million years ago a large chunk of central and
southern
Europe were likely to have been under the waters of the Tethys. (sea levels
would have higher 20 Mya, with less water locked up as ice).
Closure of the Tethys
http://www.uwgb.edu/dutchs/platetec/closteth.htm
Note on the first map - the sea is estimated have reached as far north as
southern Germany/Swabia 20 Mya...

Yes, Engelswies 17 Ma was probably a coast or delta.
The Engelswies tooth is thought to belong to Griphopith, a Miocene ape c
15 Ma (Austriaco=Griphopith) that was possibly more "advanced" than
Helio=Afro=Morotopith.

--marc

_____

> Africa is regarded as the centre for the evolution of humans & their
> precursors.
> Yet long before modern humans left Africa some 125 ka, their antecedents
> migrated from Africa to Eurasia many times, as is documented by fossils.
> How often, when & why hominoids went "out of Africa" is still a hotly
> debated field of intense research.
> Possibly, the first wave of emigration occurred at 17 Ma, as documented
>by
> finds in the Swabian N-Alpine foreland basin, SW of Sigmaringen.
> Researchers from Tübingen cs (JHE 2011) successfully pinpointed the age
>of
> a molar tooth at 17-17.1 Ma ...

There possibly was no land bridge between the two continents before 17/19
million years ago (Arabia the bit that is broke of Africa, when Africa hit
Europe, probably provided the first land link when the eastern end of the
Tethys was finally closed by Africa moving northwards).

Sicily might provide an older 'European' ape fossil, as Sicily was once a
bit of Africa. (Sicily could have provided a land bridge to Europe when
sea levels were low).

[quote]
"Was Sicily ever attached to Africa or to mainland Italy? It almost
certainly
was, but even today Sicily is only 3 kilometers from Calabria at the
narrows
of the Strait of Messina, and just 160 kilometers from the African coast.
Sicily's most southern point, near Ispica, is farther south than parts of
the
Tunisian coast, and while much of Sicily's flora and fauna are colsely
related
to those of peninsular Italy others show a closer affinity with Africa.
Prehistoric fossils of large mammals discovered in caverns and during
excavations around the island suggest that a land bridge existed in the
remotest times."

Sicily: An Island Poised Between Europe, Africa and Asia

> It is thus the oldest known Eurasian hominoid found to date.
> The owner of the tooth once inhabited a lake-side landscape with
> subtropical vegetation in a warm-humid climatic zone.
> Today, there is an abandoned quarry at the locality known among
> palaeontologists for its fossiliferous layers.
> ... the find itself dates to June 24th 1973 ... Only in 2001 was the
>molar
> taken under scrutiny, and determined as a hominoid fossil ...
> ... the mean yearly Tp was c 20°C in the area of what is now S-Germany,
> some 11°C above today's conditions. Winters were frost-free.
> There was a swamp to the S of the lake, full of reed-beds & a coast-line
> of trees, palm trees (amongst them the climbing rattan palms), lianas,
> ferns & grasses.
> To the N was a slope covered by an evergreen forest. This vegetation is
> unique in the circum-Alpine area.
> "The chronologic relationships support the idea that the Engelswies
> hominoid was a descendent of Early Miocene Afro-Arabian afropithecins."
> This find is thus the earliest known trace of hominoids which immigrated
> to Eurasia from Africa ...
> Böhme M cs 2011 JHE doi 10.1016/j.jhevol.2011.04.012
> Bio-magnetostratigraphy and environment of the oldest Eurasian hominoid
> from the Early Miocene of Engelswies (Germany)
>

A more interesting, an more important ancestor 20 (20.6) Mya would have
been Moroto (Morotopithecus) in eastern Africa.  That had a orthograde
trunk posture (vertical posture).

>
> Apparently it was warm enough 15 to 20 million years ago for trees to
> grow on the coasts of Antarctica... if it was this warm at the poles,
> could this have resulted in more arid climate in Africa...
>
> [ABSTRACT]
> "From 20 to 15 million years (Myr) ago, a period of global warmth
> reversed the previous ice growth on Antarctica, leading to the
> retreat of the West Antarctic Ice Sheet and the contraction of the
> East Antarctic Ice Sheet1, 2. Pollen recovered from the Antarctic
> shelf indicates the presence of substantial vegetation on the margins
> of Antarctica 15.7 Myr ago3. However, the hydrologic regime that
> supported this vegetation is unclear. Here we combine leaf-wax
> hydrogen isotopes and pollen assemblages from Ross Sea sediments
> with model simulations to reconstruct vegetation, precipitation and
> temperature in Antarctica during the middle Miocene. Average leaf-wax
> stable hydrogen isotope (&D) values from 20 to 15.5 Myr ago
> translate to average -D values of 50‰ for precipitation at
> the margins of Antarctica, higher than modern values. We find that
> vegetation persisted from 20 to 15.5 Myr ago, with peak expansions
> 16.4 and 15.7 Myr ago coinciding with peak global warmth and
> vegetation growth. Our model experiments are consistent with a
> local moisture source in the Southern Ocean6. Combining proxy
> measurements with climate simulations, we conclude that summer
> temperatures were about 11°C warmer than today, and that there
> was a substantial increase in moisture delivery to the Antarctic
> coast."
>
> Hydrologic cycling over Antarctica during the middle Miocene warming
> http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1498.html

#59514 From: Marc Verhaegen <m_verhaegen@...>
Date: Tue Jun 19, 2012 8:50 pm
Subject: human monogamy?
aquape
Send Email Send Email
 
Human origins and the transition from promiscuity to pair-bonding

Sergey Gavrilets 2012 PNAS 109:9923-8

A crucial step in recent theories of human origins is the emergence of
strong pair-bonding between males & females accompanied by
- a dramatic reduction in the male-to-male conflict over mating &
- an increased investment in offspring.

How such a transition from promiscuity to pair-bonding (?? gibbons are
monogamous... --mv) could be achieved is puzzling.
Many spp would, indeed, be much better off evolutionarily if the effort
spent on male competition over mating was re-directed to increasing female
fertility or survivorship of
offspring. (group selection!! The man hasn't heard of sociobiology?? --mv)
Males, however, are locked in a "social dilemma", where shifting one's
effort from "appropriation" to "production" would give an advantage to
free-riding competitors, and
therefore, should not happen.

Here, I first consider simple models for 4 prominent scenarios of the
human transition to pair-bonding:
- communal care,
- mate guarding,
- food for mating &
- mate provisioning.

I show that the transition is not feasible under biologically relevant
conditions in any of these models.
Then, I show that the transition can happen if one accounts for
- male heterogeneity,
- assortative pair formation &
- evolution of female choice & faithfulness.

This process is started when low-ranked males begin using an alternative
strategy of female provisioning.
At the end, except for the top-ranked individuals, males invest
exclusively in provisioning females who have evolved very high fidelity to
their mates.

My results point to the crucial importance of female choice, and emphasize
the need for incorporating between-individual variation in theoretical &
empirical studies of social dilemmas & behaviors.

#59515 From: Marc Verhaegen <m_verhaegen@...>
Date: Tue Jun 19, 2012 8:56 pm
Subject: Religion as a means to assure paternity
aquape
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Religion as a means to assure paternity
BI Strassmann cs 2012 PNAS 109:9781-5

The sacred texts of 5 world religions (Buddhism, Christianity, Hinduism,
Islam, Judaism) use similar belief systems to set limits on sexual
behavior.
We propose
- This similarity is a shared cultural solution to a biological problem:
male uncertainty over the paternity of offspring.
- Religious practices that more strongly regulate female sexuality should
be more successful at promoting paternity certainty.

Using genetic data on 1706 father­son pairs, we tested this hypothesis in
a traditional African population in which multiple religions (Islam,
Christianity, indigenous) co-exist in the same families & villages.

We show :
The indigenous religion enables males to achieve less cuckoldry (1.3 vs
2.9 %) by enforcing the honest signaling of menstruation.
All 3 religions share tenets aimed at the avoidance of extra-pair
copulation.

Our findings provide evidence for high paternity certainty in a
traditional African population,
they shed light on the reproductive agendas that underlie religious
patriarchy.

#59516 From: Marc Verhaegen <m_verhaegen@...>
Date: Tue Jun 19, 2012 9:02 pm
Subject: Direct reciprocity in structured populations
aquape
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Direct reciprocity in structured populations
Matthijs van Veelen, Julián García, David G Rand & Martin A Nowak 2012
PNAS 109:9929-34

Reciprocity & repeated games have been at the center of attention when
studying the evolution of human cooperation.
Direct reciprocity is considered to be a powerful mechanism for the
evolution of cooperation,
it is generally assumed that it can lead to high levels of cooperation.

Here we explore an open-ended infinite strategy space, where every
strategy that can be encoded by a finite state automaton is a possible
mutant.

1) We find that direct reciprocity alone does not lead to high levels of
cooperation.
Instead, we observe perpetual oscillations between cooperation &
defection, with defection being substantially more frequent than
cooperation:
"indirect invasions" remove equilibrium strategies: every strategy has
neutral mutants, which in turn can be invaded by other strategies.

2) Another mechanism for the evolution of cooperation is assortment
because of population structure.
Here we develop a theory that allows us to study the synergistic
interaction between direct reciprocity & assortment.
This framework is particularly well suited for understanding human
interactions, which are typically repeated, and occur in rel.fluid, but
not unstructured populations.
We show that if repeated games are combined with only a small amount of
assortment, then natural selection favors the behavior typically observed
among humans:
high levels of cooperation implemented using conditional strategies.

#59517 From: Jack Barnes <teamyin@...>
Date: Wed Jun 20, 2012 4:06 am
Subject: Re: human monogamy?
needninfo
Send Email Send Email
 
Marc,
Actually Asians have been shown to have been almost exclusively monogamous
over time.   This is another reason against the out-of africa theory.   In
Africa you needed the group to survive the pressures of the heat, malaria,
tse tse fly, predators and most of all viral infections like PTERV.

Homo entered asia with the ability as a bipedal creature, able to swim and
as monogamous couples, that is why our oldest genes are asian not african
and why asians are monogamous.
http://ts-si.org/relationships/23561-modern-homo-sapiens-monogamy-and-polygamy

1.6mya Homo grew and expanded toward Africa.   Africa transformed homo into
a socially intelligent and hairless creature.  Monogamy is NOT a part of
current african tribal society and neoteny of features became prevalent as
we became distance runners.  Look at the bushmen of today.  Long necks,
rounded head, hairless and flat chested, all to survive the heat of the
savannah.

As Steven J. Gould so aptly pointed out.  Humanity is in the process of
domestication, hence why our robust features have been thinning over time.

-Jack

On Tue, Jun 19, 2012 at 3:50 PM, Marc Verhaegen <m_verhaegen@...>wrote:

> **
>
>
> Human origins and the transition from promiscuity to pair-bonding
>
> Sergey Gavrilets 2012 PNAS 109:9923-8
>
> A crucial step in recent theories of human origins is the emergence of
> strong pair-bonding between males & females accompanied by
> - a dramatic reduction in the male-to-male conflict over mating &
> - an increased investment in offspring.
>
> How such a transition from promiscuity to pair-bonding (?? gibbons are
> monogamous... --mv) could be achieved is puzzling.
> Many spp would, indeed, be much better off evolutionarily if the effort
> spent on male competition over mating was re-directed to increasing female
> fertility or survivorship of
> offspring. (group selection!! The man hasn't heard of sociobiology?? --mv)
> Males, however, are locked in a "social dilemma", where shifting one's
> effort from "appropriation" to "production" would give an advantage to
> free-riding competitors, and
> therefore, should not happen.
>
> Here, I first consider simple models for 4 prominent scenarios of the
> human transition to pair-bonding:
> - communal care,
> - mate guarding,
> - food for mating &
> - mate provisioning.
>
> I show that the transition is not feasible under biologically relevant
> conditions in any of these models.
> Then, I show that the transition can happen if one accounts for
> - male heterogeneity,
> - assortative pair formation &
> - evolution of female choice & faithfulness.
>
> This process is started when low-ranked males begin using an alternative
> strategy of female provisioning.
> At the end, except for the top-ranked individuals, males invest
> exclusively in provisioning females who have evolved very high fidelity to
> their mates.
>
> My results point to the crucial importance of female choice, and emphasize
> the need for incorporating between-individual variation in theoretical &
> empirical studies of social dilemmas & behaviors.
>
>
>


[Non-text portions of this message have been removed]

#59518 From: Heather Twist <HeatherTwist@...>
Date: Wed Jun 20, 2012 5:22 am
Subject: Re: Religion as a means to assure paternity
heathertwist2
Send Email Send Email
 
Many of the religions also enforce patriarchy in general, that the head male
is in control by divine fiat. Mormonism originally took this to an extreme,
where the male gets to decide which wives to resurrect to the afterlife.
Also
that a woman could leave her current husband, to marry a more "holy" male
(someone
higher up in the religious hierarchy) to ensure life everlasting. The fact
that some
women left their un-holy non-Mormon husbands to marry Mormons, was one
of the reasons the Mormons got driven out.

Anyway, given the obvious patriarchy of most religions, it' been a wonder
to me
that the women are among the most supportive of "religion" in general. Much
of
the work in the average church is done by a large group of women, with a
small
group of males as the titular head. So what do the women get out of it?

Well, the men might get assurance of paternity. But those same religions
also
encourage men to be "good husbands" which means not having sex outside the
household, providing a decent income, not leaving, not getting drunk too
much,
and treating wives fairly. Since the big issue for women is how to provide
for the
children (a hard job when you are also caring for young children), strongly
encouraging the men to care for their families is a very good thing.

Your average ape male only needs to fight off competitor males. But a human
male also needs to help raise the kids, or at least help provide for them.


On Tue, Jun 19, 2012 at 1:56 PM, Marc Verhaegen <m_verhaegen@...>wrote:

> **
>
>
> Religion as a means to assure paternity
> BI Strassmann cs 2012 PNAS 109:9781-5
>
> The sacred texts of 5 world religions (Buddhism, Christianity, Hinduism,
> Islam, Judaism) use similar belief systems to set limits on sexual
> behavior.
> We propose
> - This similarity is a shared cultural solution to a biological problem:
> male uncertainty over the paternity of offspring.
> - Religious practices that more strongly regulate female sexuality should
> be more successful at promoting paternity certainty.
>
> Using genetic data on 1706 father­son pairs, we tested this hypothesis in
> a traditional African population in which multiple religions (Islam,
> Christianity, indigenous) co-exist in the same families & villages.
>
> We show :
> The indigenous religion enables males to achieve less cuckoldry (1.3 vs
> 2.9 %) by enforcing the honest signaling of menstruation.
> All 3 religions share tenets aimed at the avoidance of extra-pair
> copulation.
>
> Our findings provide evidence for high paternity certainty in a
> traditional African population,
> they shed light on the reproductive agendas that underlie religious
> patriarchy.
>
>
>



--
Heather Twist
http://eatingoffthefoodgrid.blogspot.com/


[Non-text portions of this message have been removed]

#59519 From: Marc Verhaegen <m_verhaegen@...>
Date: Wed Jun 20, 2012 6:46 am
Subject: Re: Religion as a means to assure paternity
aquape
Send Email Send Email
 
>
>Many of the religions also enforce patriarchy in general, that the head
>male
>is in control by divine fiat. Mormonism originally took this to an
>extreme,
>where the male gets to decide which wives to resurrect to the afterlife.
>Also
>that a woman could leave her current husband, to marry a more "holy" male
>(someone
>higher up in the religious hierarchy) to ensure life everlasting. The fact
>that some
>women left their un-holy non-Mormon husbands to marry Mormons, was one
>of the reasons the Mormons got driven out.
>
>Anyway, given the obvious patriarchy of most religions, it' been a wonder
>to me
>that the women are among the most supportive of "religion" in general.
>Much
>of
>the work in the average church is done by a large group of women, with a
>small
>group of males as the titular head. So what do the women get out of it?
>
>Well, the men might get assurance of paternity. But those same religions
>also
>encourage men to be "good husbands" which means not having sex outside the
>household, providing a decent income, not leaving, not getting drunk too
>much,
>and treating wives fairly. Since the big issue for women is how to provide
>for the
>children (a hard job when you are also caring for young children),
>strongly
>encouraging the men to care for their families is a very good thing.

Good analysis IMO, Heather: as often, the female role seems to have been
"forgotten" in the paper.

>Your average ape male only needs to fight off competitor males. But a
>human
>male also needs to help raise the kids, or at least help provide for them.

Yes, there are a lot of monogamous primates (monogamy is not uncommon when
visibility is low), and since gibbons are monogamous (in the biological
sense) & all the other apes' social systems are directly derivable from
ancestral monogamy, it's likely that the hominoid LCA was monogamous. But
it's only in humans among hominoids that the man has generally an
important role in raising & feeding the children.  I wonder whether a
diving alternation by mother & father (as proposed by DD) could be (part
of) the explanation for this.

--marc

______

>> Religion as a means to assure paternity
>> BI Strassmann cs 2012 PNAS 109:9781-5
>>
>> The sacred texts of 5 world religions (Buddhism, Christianity, Hinduism,
>> Islam, Judaism) use similar belief systems to set limits on sexual
>> behavior.
>> We propose
>> - This similarity is a shared cultural solution to a biological problem:
>> male uncertainty over the paternity of offspring.
>> - Religious practices that more strongly regulate female sexuality
>>should
>> be more successful at promoting paternity certainty.
>>
>> Using genetic data on 1706 father­son pairs, we tested this hypothesis
>>in
>> a traditional African population in which multiple religions (Islam,
>> Christianity, indigenous) co-exist in the same families & villages.
>>
>> We show :
>> The indigenous religion enables males to achieve less cuckoldry (1.3 vs
>> 2.9 %) by enforcing the honest signaling of menstruation.
>> All 3 religions share tenets aimed at the avoidance of extra-pair
>> copulation.
>>
>> Our findings provide evidence for high paternity certainty in a
>> traditional African population,
>> they shed light on the reproductive agendas that underlie religious
>> patriarchy.

#59520 From: Heather Twist <HeatherTwist@...>
Date: Wed Jun 20, 2012 8:29 am
Subject: Re: Religion as a means to assure paternity
heathertwist2
Send Email Send Email
 
On Tue, Jun 19, 2012 at 11:46 PM, Marc Verhaegen <m_verhaegen@...>wrote:

> **
>
>
> >
> >Many of the religions also enforce patriarchy in general, that the head
> >male
> >is in control by divine fiat. Mormonism originally took this to an
> >extreme,
> >where the male gets to decide which wives to resurrect to the afterlife.
> >Also
> >that a woman could leave her current husband, to marry a more "holy" male
> >(someone
> >higher up in the religious hierarchy) to ensure life everlasting. The fact
> >that some
> >women left their un-holy non-Mormon husbands to marry Mormons, was one
> >of the reasons the Mormons got driven out.
> >
> >Anyway, given the obvious patriarchy of most religions, it' been a wonder
> >to me
> >that the women are among the most supportive of "religion" in general.
> >Much
> >of
> >the work in the average church is done by a large group of women, with a
> >small
> >group of males as the titular head. So what do the women get out of it?
> >
> >Well, the men might get assurance of paternity. But those same religions
> >also
> >encourage men to be "good husbands" which means not having sex outside the
> >household, providing a decent income, not leaving, not getting drunk too
> >much,
> >and treating wives fairly. Since the big issue for women is how to provide
> >for the
> >children (a hard job when you are also caring for young children),
> >strongly
> >encouraging the men to care for their families is a very good thing.
>
> Good analysis IMO, Heather: as often, the female role seems to have been
> "forgotten" in the paper.
>
> >Your average ape male only needs to fight off competitor males. But a
> >human
> >male also needs to help raise the kids, or at least help provide for them.
>
> Yes, there are a lot of monogamous primates (monogamy is not uncommon when
> visibility is low), and since gibbons are monogamous (in the biological
> sense) & all the other apes' social systems are directly derivable from
> ancestral monogamy, it's likely that the hominoid LCA was monogamous. But
> it's only in humans among hominoids that the man has generally an
> important role in raising & feeding the children. I wonder whether a
> diving alternation by mother & father (as proposed by DD) could be (part
> of) the explanation for this.
>
> --marc
>

I don't know about diving, but having raised two of my own, the "carrying"
part is HUGE. In one of the early hominids, it is mentioned that the toe is
such that the baby could not hold on to fur, so the adult would have to
carry it in arms. I used a sling. I could still garden, cook etc, but it
was more difficult for sure, and I got really adept at working with one
arm. We required that babysitters etc. also carry the baby, always. She
turned out great, but I think we underestimate the amount of work it takes
to REALLY raise a human infant right.

If we had been in the tropics, and she could have floated while I dived
(maybe another caretaker) it could have worked. Or someone on shore, or in
the shallows. In water, the fact someone is male or female isn't as
important, since muscle strength doesn't count for as much. Strong arm
muscles can throw a spear further, but not under water. I did actually
fight people when I was a teen, in water ... they were stronger and more
aggressive, but I knew how to hold my breath, and just dragged them under
until they needed air. It's a very different game!





> ______
>
> >> Religion as a means to assure paternity
> >> BI Strassmann cs 2012 PNAS 109:9781-5
> >>
> >> The sacred texts of 5 world religions (Buddhism, Christianity, Hinduism,
> >> Islam, Judaism) use similar belief systems to set limits on sexual
> >> behavior.
> >> We propose
> >> - This similarity is a shared cultural solution to a biological problem:
> >> male uncertainty over the paternity of offspring.
> >> - Religious practices that more strongly regulate female sexuality
> >>should
> >> be more successful at promoting paternity certainty.
> >>
> >> Using genetic data on 1706 father­son pairs, we tested this hypothesis
> >>in
> >> a traditional African population in which multiple religions (Islam,
> >> Christianity, indigenous) co-exist in the same families & villages.
> >>
> >> We show :
> >> The indigenous religion enables males to achieve less cuckoldry (1.3 vs
> >> 2.9 %) by enforcing the honest signaling of menstruation.
> >> All 3 religions share tenets aimed at the avoidance of extra-pair
> >> copulation.
> >>
> >> Our findings provide evidence for high paternity certainty in a
> >> traditional African population,
> >> they shed light on the reproductive agendas that underlie religious
> >> patriarchy.
>
>
>



--
Heather Twist
http://eatingoffthefoodgrid.blogspot.com/


[Non-text portions of this message have been removed]

#59521 From: Marc Verhaegen <m_verhaegen@...>
Date: Wed Jun 20, 2012 8:11 pm
Subject: Re: Re: Darren Naish article on AAT/Aquarboreal Theory
aquape
Send Email Send Email
 
I just answered them this (if somebody can find Naish's email address,
please let me know, then I can send it him directly):

Naish's post shows how much misunderstanding there still is about AAT, or
better about the Littoral Theory.
Our ancestors' littoral past has nothing to do with Ardipith, Sahelanthropus
or australopiths, of course: it was about Pleistocene Homo spreading along
coasts & rivers to different continents & even islands, eg, Flores c 900 ka
>18 km oversea! There's nothing mysterious about it, and we have all the
fossils: all archaic Homo fossils are found in littoral sediments from
Mojokerto to the Cape to Pakefield & Boxgrove. It's obvious they did not get
there running over plains! They simply followed the coasts & the rivers
inland, where these dextrous omnivores fed on different sorts of waterside
foods: stranded whales, drowned ungulates, cattails & cane, birds' eggs,
shell- & crayfish etc. It was there that we got our huge brains (DHA), fur
loss & fat layers, our head-spine-legs in 1 line, our external nose etc.
Naish's post has only 1 +-sensible sentence: "... at least some fossil
humans & human relatives foraged on shorelines or in mangroves, waded in
shallows, or ate aquatic foods like crabs, stranded fish & shellfish." This
is much too weak, of course: archaic Homo shows pachyosteosclerosis
(google), a feature that is typically & exclusively seen in slow & shallow
littoral divers: among mammals, eg, sea-cows, walruses & several fossils
(AFAIK: Ichthyolestes, Pakicetus, Basilosaurus, Zygorhiza, Ambulocetus,
Indohyus, Odobenocetops, Valenictus, Kolponomos & some Thalassocnus spp).
If one wants to write something on the littoral theory, one has first to in
form a bit.
In 1995, professor Phillip Tobias, in his Daryll Forde Memorial Lecture at
University College, London, stated of the Savannah Hypothesis: "We were all
profoundly and unutterably wrong! All the former savannah supporters
including myself must now swallow our earlier words ..." In spite of this,
the savannah ideas are apparently still taken for granted in most popular
books & articles on human evolution. We think the death of professor Tobias
must be an opportunity for paleo-anthropologists to finally get rid of the
dry savannah fantasies.
It was Tobias' predecessor at the Witwatersrand University, Raymond Dart,
who helped the savannah ideas to become generally accepted. In the 1920s,
geologists thought the climate in South Africa had not changed since the
Pliocene, so Dart concluded that the Taung child (a human ancestor, he
believed) had lived in dry grasslands. We now know that Taung was possibly
no human ancestor, and moreover lived in "a more forested habitat, with
denser cover along waterways" (Berger & Clarke 1995). If some hominids lived
in savannahs, it must have been along the forested rivers, swamps & lakes
there, where their fossils have been found.
H.erectus, with its extremely heavy skeleton could not have practiced
endurance running (a still popular fantasy, even among
paleo-anthropologists).
One of the last publications of Professor Tobias was "Revisiting Water and
Hominin Evolution", the first chapter of an ebook devoted to our ancestors'
waterside evolution:
Mario Vaneechoutte, Algis Kuliukas & Marc Verhaegen eds 2011 Bentham Science
Publications,
"Was Man More Aquatic in the Past? Fifty Years after Alister Hardy:
Waterside Hypotheses of Human Evolution".
Although it is clear that Pleistocene Homo was more aquatic than Homo
sapiens is today, how aquatic they were is still debatable. Any scientific
discussion of human evolution should take into account this ebook, which
contains contributions of all major proponents of waterside hypotheses.
Please also google "econiche Homo" & for ape evolution "aquarboreal", and
please contact me for our recent paper in HOMO - Journal of Comparative
Human Biology 62:237­247, 2011 "Pachyosteosclerosis suggests archaic Homo
frequently collected sessile littoral foods"
Marc Verhaegen & Stephen Munro 2011:
"Fossil skeletons of Homo erectus and related specimens typically had heavy
cranial and postcranial bones, and it has been hypothesised that these
represent adaptations, or are responses, to various physical activities such
as endurance running, heavy exertion, and/or aggressive behavior. According
to the comparative biological data, however, skeletons that show a
combination of disproportionally large diameters, extremely compact bone
cortex, and very narrow medullary canals are associated with aquatic or
semi-aquatic tetrapods that wade, and/or dive for sessile foods such as
hard-shelled invertebrates in shallow waters. These so-called
pachyosteosclerotic bones are less supple and more brittle than
non-pachyosteosclerotic bones, and marine biologists agree that they
function as hydrostatic ballast for buoyancy control. This paper discusses
the possibility that heavy skeletons in archaic Homo might be associated
with part-time collection of sessile foods in shallow waters."






>http://sciencefocus.com/feature/life/aquatic-apes

Thanks a lot, DD.
The poor man has still no idea what AAT is about. He still thinks AAT is
about apiths ("hominids").

Were we once aquatic apes?
Darren Naish examines(?? Naish lets us know his prejudices --mv) a debate
that's lasted 50 years.
In 1960, the marine biologist Sir Alister Hardy proposed that humans had
gone through an aquatic phase in their history. Hardy pointed to human
swimming abilities, hairlessness, hair tracts patterns and the presence of
subcutaneous fat in support of his idea. Hardy's hypothesis was mentioned
by Desmond Morris in his 1967 book The Naked Ape, but it was television
script-writer Elaine Morgan who made the Aquatic Ape Hypothesis (AAH)
famous thanks to her several books, especially The Aquatic Ape (published
in 1982). Morgan expanded on Hardy's idea, arguing that many additional
peculiarities of human biology and anatomy pointed to an aquatic phase in
human ancestry. A 1987 conference devoted to the AAH resulted in a
technical volume containing 22 contributions, the more scholarly of which
argued against the AAH.(the less informed, he means... --mv)
It has been argued that German anatomist Max Westenhöfer supported the AAH
in his work of the 1920s and 30s. Westenhöfer interpreted an aquatic
ancestry for humans within his "initial bipedalism" hypothesis. According
to this idea, humans are the most structurally primitive of primates and
the ancestors of all other primate groups. This work is
generally regarded as "fringe" science today.(by people like Naish... --mv)
Today, the AAH has mostly failed to win adherents and is not considered
seriously by mainstream primatologists or anthropologists.(not impossible,
but unproven --mv) There are several reasons for this. One is that the
basic arguments are erroneous. That is, the supposedly "aquatic" features
of humans are either not unique among primates, or are not like those of
aquatic mammals as the AAH argues.(nonsense, eg, all furless + fat mammals
spend a lot of time in the water --mv) Some monkeys are capable swimmers
and divers, for example.(=anti-AAT argument? :-D --mv) The "diving reflex"
is present in other primates and indeed in other mammals, the babies of
just about all mammals behave the same when placed in water, and there are
non-human primates that sweat as much as humans do. The descended human
larynx is not unique to aquatic species, nor are humans unique in their
hair tract patterns, in possessing hymens, in the position of their fat
deposits, and so on.(so? irrelevant - I never said otherwise  --mv)
Fossil evidence also fails to support the AAH.(nonsense: all archaic Homo
are found in waterside sediments, often littoral, AFAWK always next to
edible shellfish --mv) Morgan and her supporters argued against the idea
that humans owed their anatomy to a life in dry, hot grasslands, but this
is a straw-man argument since early fossil members of the human lineage
were woodland- or forest-adapted animals. Furthermore, fossil hominids
lack adaptations special to mammals that regularly swim or forage in
water.(:-D eg, pachyostosis  --mv) The supposed peculiarities of humans
are well explained by adaptation to a lifestyle where sweating,(:-DDD  the
most sweating mammals are humans & sealions on land  -mv) complex
formation of sounds in communication, and exploitation of scarce, fatty
foods were important.
Some modern supporters of the AAH argue that great apes went through an
"aquarboreal" phase in which they waded and swam in swampy forests,
feeding on molluscs and fruit. Members of the human lineage, they argue,
became bipedal in this context and remained tied to waterside resources as
coastal foragers. It is possible that at least some fossil humans
and human relatives foraged on shorelines or in mangroves, waded in
shallows, or ate aquatic foods like crabs, stranded fish and
shellfish.(the first sensible sentence... --mv)
However, there are no indications that such a lifestyle, if it existed,
left any obvious mark on human anatomy, so this watered-down idea of a
link with aquatic environments cannot be considered in the same ballpark
as the AAH.(platycephaly, platymeria, ear exostoses, pachyostosis, flaring
ilia, short tibiae, huge brain etc.etc.  --mv)
Despite a huge number of recent fossil hominid discoveries, fossil
evidence that might support the AAH has not appeared.(:-D  Homo flew to
Flores?  --mv) The evidence from primate physiology, behaviour and anatomy
also fails to support it.(ridiculous statement  --mv)
Overall, the AAH remains a historical curiosity, but not an acceptable
explanation for human evolution. It is, many argue, dead in the
water.(we're not interested in the nonsense Naish "argues"...  --mv)
Darren Naish is a palaeozoologist at the University of Southampton (a pity
for the Univ.of Southampton  --mv)









[Non-text portions of this message have been removed]

#59522 From: "dons3148" <dons3148@...>
Date: Thu Jun 21, 2012 11:38 am
Subject: Re: Bonobo Genome Completed
dons3148
Send Email Send Email
 
--- In AAT@yahoogroups.com, "Rob Dudman" <ausell@...> wrote:


Hello Rob...



> Hello Bill..........
>
> >
> > I would say the differences between bonobos and their more      >
> aggressive kin are likely to be largely behavioral, whether they > are the
> result of genetic or an adaptive differences (apparently   > the bonobos did
> not face much if any competition from the        > gorilla south of the
> Congo river) is an another question.             >
> and............
> >
> > Note the Congo river acts to separate the bonobos from the        >
> eastern chimpanzee as claimed, but another river to the north    > splits
> the territory of the eastern chimpanzee in two, yet does    > seem to be a
> barrier for the eastern chimpanzee on either side of > the river. I would
> say the main role of the Congo river as such   > seems to have been to keep
> the gorilla to the north, while           > allowing the bonobos south of
> the river to adapt without             > competition from the gorilla.
> >
>
> As I understand it, the general idea seems to go something like this: the
> formation of the Congo River permanently separated the chimp population
> south of the river from those north of the river. The southern population
> did not have to compete with gorillas for resources and the resultant plenty
> then led to less intraspecific aggressive behaviour, which in turn led to a
> neotenous trend in adaptation.
>
> It's neat, but surely an early and predictable consequence of such
> uncontested resources would be a rise in population density and, by now, a
> spread to all parts of the rainforest south of the river and this is not the
> case. More to the point, north of the river there is little competition for
> resources between chimps and gorillas....... they specialize in different
> foods and the huge size of the rainforest habitat allows the two species to
> be widely separated from each other and therefore not troubled by
> competition for the few resources shared by the two species. The idea that a
> lack of competition from gorillas in a vastness like the African rainforest
> would be the trigger for the social changes so characteristic of the bonobo,
> is simply not at all compelling IMO.
>
> (Given the numbers and distribution of the two species in the vast
> rainforest north of the Congo River, it could well be the case that all but
> a miniscule percentage of the chimps who have ever lived never saw or even
> smelled a gorilla and vice-versa. Come to think of it, by the age of fifteen
> I'd probably seen more gorillas than most chimps who have ever lived and I
> grew up in Devonshire!)
>


On the other hand some would say that we cannot ascertain the
levels of the ancestral population and distribution and behaviour
of gorilla and chimpanzee today, by looking at their numbers and
distribution in the rainforest today. (in other words next to
nothing is known about the ancestors of both species, their
numbers, their distribution, how they interacted or where
they originated)...

I tend to the view that the extant chimpanzee, the various sub-species
and the bonobos as simply creatures of the Pleistocene (as is modern
Man). The Pliocene ancestor of the extant chimpanzee could have been
entirely different from the chimpanzee we love and hate today (for
example it could have been a much smaller, more arboreal animal), in
the same way AMHs today differ somewhat from their terrestrial
ancestors of two to four million years ago.



> The three characteristics of bonobo life that clearly differentiate them
> from the common chimp are their comparative lack of intra- specific
> aggression, their use of simulated copulation to ease social tension and
> their enjoyment of play well into adulthood.
> Bearing in mind that human toddlers will massage their genital area to ease
> anxiety, the neotenous trend that also extended playfulness in bonobos could
> well have extended the use of genital massage into a broader social setting.
>


A fourth bonobo characteristic and the one that probably determinates
bonobo behaviour, is that among bonobos the female is the
dominant sex ...

http://evolutionaryanthropology.duke.edu/research/3chimps/chimps-bonobos




> But the comparative lack of intraspecific aggression is not only the
> characteristic which can most readily 'set the stage' for the other two,
> it's also the most likely to have been genetically determined. One
> possibility would be that the group first isolated south of the river
> happened to lack a chimp version of the MAOA-L variation found in a small
> percentage of humans (commonly called 'the warrior gene'). Now that the
> bonobo genome is complete someone might think to look.
>
> >
> > With the presence of the a'piths in eastern Africa (probably       >
> related to Man) and in southern Africa (unrelated to Man)          >
> millions of years ago, I have tended to presume that the west     > Africa
> chimpanzee or its ancestor was the origin of today's        > various
> chimpanzee (sub)species...spreading into central Africa > and subsequently
> east Africa when the southern a'piths became > extinct.
> >
>
> Until I can find an explanation for our lack of those RV markers that
> doesn't involve special-pleading, then I'm forced to the null that the
> A'piths are not more closely related to us than chimps and in fact I still
> have the opinion that the most likely relational distance is probably the
> same in both cases......ie., there was an A/H/P LCA; with neither A. nor H.
> finding refuge in the rainforest after the divergence.
>


A year or two ago I would have agreed with you, but now I am no
longer so certain that the a'piths (the gracile ones) can be so
easily dismissed…   one reason being in the last year here have
been more insights into how early hominin like `Lucy' walked
upright...

(there were probably several hominins at around that date that
could walk upright on their feet, but 'Lucy'is the only one we
know about that had human-like feet)


Human-like external function of the foot, and fully upright
gait, confirmed in the 3.66 million year old Laetoli
hominin footprints

http://rsif.royalsocietypublishing.org/content/9/69/707.full






> > The territory of central chimpanzee today is approximately        >
> directly south of Chad, while that of the west African                  >
> chimpanzee is to the west or south-west... As to how far the      > ancestor
> of the extant chimpanzee would have had to move in    > terms of distance,
> it may not have been problematic ... as it       > could have depended on
> how fast the rainforest retreated            > southwards or broke-up in the
> face of climate change over         > north-Africa (if it was a gradual
> retreat, possibly the ancestor of > the extant chimpanzee simply followed it
> southwards over          > generations).
> >
>
> I understand that the Megalake was so big that it reached south to the
> rainforest and while the climatic consequences of the MSC would have been
> felt that far south (the evaporating Med was being dumped somewhere and
> probably expanded the northern limits of the rainforest), I think it would
> have been the draining of the lake that caused the (A)/H/P LCA that had
> previously exploited the southern edges of the Megalake to then move further
> south and into the rainforest to become the ancestral chimps. Central and/or
> western, I don't think that they had very far to go and given what a rapidly
> draining lake leaves behind, I think they probably did it quickly.
>


If the northern limits of the rainforest had encompassed what is
now Nigeria, stretched westwards towards the Atlantic and the `home'
of the west African chimpanzee  its northern edge could have reached
the southern shore of the Mega lake ((Lake chad being located today
where the borders of Chad, Nigeria and the Cameroon meet).



> > The Kenyan fossils, could be those of an ancestor of the extant
> > chimpanzee who strayed too far east (like those remains of        > a'pith
> in Chad (who is said to have strayed too far west of the     > Rift!)...
> >
>
> If I may misquote that great paleoanthropologist Gerry Lee Lewis: 'There's a
> whole lotta strayin' goin' on.'
>
> :-)
>
> What Abel does show is that from a hominid point of view there was a viable
> 'ecological corridor' between Chad and East Africa c. 3.5 Mya. The
> affinities between A.bahrelghazali and A.afarensis  indicate that spread
> over those many kms and many generations the central African arafensis had
> changed enough to become a subspecies. One of the safest predictions in
> paleoanthropology surely has to be that there are more A'pith fossils
> waiting to be found between the Abel site and the Lucy site.
>
> Of interest..........
>
>  'Two new Mio-Pliocene Chadian hominids enlighten Charles Darwin's 1871
> prediction'
> By Michel Brunet
> <http://rstb.royalsocietypublishing.org/search?author1=Michel+Brunet&sortspe
> c=date&submit=Submit> .
>
> http://rstb.royalsocietypublishing.org/content/365/1556/3315.full
> __________________
>


Thanks for the links...

The a'pith species appear given their widespread distribution from
north to south and continuous presence eastern Africa for about
three million years (from around 4 Mya to 1.2 Mya), seem to have
been largely unaffected by the retrovirus that hit the ancestors
of the gorilla and the extant chimpanzee.

http://www.columbia.edu/itc/anthropology/v1007/2002projects/web/australopithecus\
/austro.html





> > Gorilla was first observed on the west coast by mariners of the
> > ancient world (Carthaginians) who sailed down the west African
> > a few thousand years ago, they seemingly mistook Gorilla for a
> > tribe of hairy women... hence the name Gorilla!
> >
> > (Guess those Carthaginians, had been at sea too long!)
> >
>
> IIRC, Hanno reported that they killed and skinned three of them...... some
> things don't change much.
>
> >
> > With regards to our previous conversation Rob, you might be       >
> interested to know Ajit Vakari and his colleagues have recently   > come out
> with a new paper, it appears to detail a more recent       > inactivation in
> the human lineage to enhance immunity from       > pathogens... pathogens
> that appear to have targeted the newborn.
> >
> > PNAS
> > Specific inactivation of two immunomodulatory SIGLEC genes
> > during human evolution
> >
> > http://www.pnas.org/content/early/2012/05/30/1119459109
> >
> > This account in Science Daily is a little confusing... as the            >
> abstract of the paper in question appears to say it occurred in       >
> common ancestor of H.ss, the Neanderthals and the Denisovans... > while this
> article places it only a few hundred thousand years ago.
> >
> > How Infectious Disease May Have Shaped Human Origins
> >
> > [Quote]
> > "In a paper published in the June 4, 2012 online Early Edition
> > of The Proceedings of the National Academy of Sciences, an
> > international team of researchers, led by scientists at the
> > University of California, San Diego School of Medicine, suggest
> > that inactivation of two specific genes related to the immune
> > system may have conferred selected ancestors of modern humans
> > with improved protection from some pathogenic bacterial strains,
> > such as Escherichia coli K1 and Group B Streptococci, the leading
> > causes of sepsis and meningitis in human fetuses, newborns
> > and infants.
> >
> > http://www.sciencedaily.com/releases/2012/06/120604155554.htm
> >
>
> In the abstract they say.......
>
> 'We describe two primate Siglecs that were rendered nonfunctional by single
> genetic events during hominin evolution after our common ancestor with the
> chimpanzee.'
>
> and
>
>
> 'Neanderthal and Denisovan genomes show human-like sequences at both loci,
> corroborating estimates that the initial pseudogenization events occurred in
> the common ancestral population of these hominins.'
>
>
> If I sneakily change 'the common ancestral population' to 'a common
> ancestral population', that's a time-window of about 5 million years! The
> abstract doesn't say which sialic acid was recognized by these Siglecs, but
> I'm game......I'll predict the time at c. 2.4-5 Mya and the acid was Neu5Gc.
>
> Rob.



A possibility, however as far as I know  Ajit Vakari  and his colleagues
have not mentioned the CMAH mutation and the loss of Neu5Gc 2.8 Mya in
what they claim was an inactivation in the human lineage, involving
the immune system...  also the event that provoked the response from the
immune system they mention, seems to have been a particularly nasty
bacterial infection, not a response to possible repeated malaria
infections which may have resulted in the inactivation
of Neu5Gc in humans some 2.8 Mya.


[Quote]
"In a paper published in the June 4, 2012 online Early Edition
of The Proceedings of the National Academy of Sciences, an
international team of researchers, led by scientists at the
University of California, San Diego School of Medicine, suggest
that inactivation of two specific genes related to the immune
system may have conferred selected ancestors of modern humans
with improved protection from some pathogenic bacterial strains,
such as Escherichia coli K1 and Group B Streptococci, the
leading causes of sepsis a" (Science Daily)

_________________________________


[Quote]
"Sialic acid-recognizing Ig-like lectins (Siglecs) are signaling
receptors that modulate immune responses, and are targeted for
interactions by certain pathogens. We describe two primate
Siglecs that were rendered nonfunctional by single genetic
events during hominin evolution after our common ancestor with
the chimpanzee. SIGLEC13 was deleted by an Alu-mediated
recombination event, and a single base pair deletion disrupted
the ORF of SIGLEC17. Siglec-13 is expressed on chimpanzee
monocytes, innate immune cells that react to bacteria.
The human SIGLEC17P pseudogene mRNA is still expressed at
high levels in human natural killer cells, which bridge innate
and adaptive immune responses. " (quote from the Abstract)

http://www.pnas.org/content/early/2012/05/30/1119459109.abstract

__________________________________



Two genes appear to have been involved, one of them...  human
SIGLEC17P appears inactive in humans but still functional in
the extant chimpanzee, whilst SIGLEC13 was effectively
deleted from the human genome!



Guess the far more interesting question is what kind bacterial
infection was it that hit the common ancestor of modern man and
the Neanderthals, which would have reduced their numbers
to just a few thousands?

Meat would be the obvious culprit as a source of bacteria...
But, a rotting carcass tends to stink as bacteria get to
work, so it's doubtful that even our early ancestors would
have touched a kill that was several days old.

However, there is a food source that may have given no
indication that it was loaded with bacteria, and that is
shellfish (the space between the shell and the flesh, being
a perfect breeding ground for bacteria) ...

Possibly in swallowing shellfish on the shore by the bucketful
on the shore half a million years ago, the common ancestor of
modern Man and the Neanderthals encountered in the shellfish
they were swallowing, a particularly nasty strain of
bacteria, that nearly wiped them out...


Bill

#59523 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 12:47 pm
Subject: "heidelbergensis"
aquape
Send Email Send Email
 
http://onlinelibrary.wiley.com/doi/10.1002/evan.21311/abstract

The status of Homo heidelbergensis (Schoetensack 1908)
Chris Stringer 2012
The species Hheid is central to many discussions about recent human
evolution:
- for some workers, it was the LCA for the subsequent spp Hs & Hn,
- others regard it as only a European form, giving rise to Hn.
Following the impact of recent genomic studies indicating hybridization
between Hs & both Hn & "Denisovans", the status of these as separate taxa
is now under discussion.
Accordingly, clarifying the status of Hheid is fundamental to the debate
about modern human origins. © 2012 Wiley Periodicals, Inc.


(we can't say much sensible on this IMO, unless we can isolate DNA from
"heidelb." fossils  --mv)

#59525 From: "dons3148" <dons3148@...>
Date: Thu Jun 21, 2012 1:42 pm
Subject: Re: "heidelbergensis" - Homo heidelbergensis
dons3148
Send Email Send Email
 
--- In AAT@yahoogroups.com, Marc Verhaegen <m_verhaegen@...> wrote:
>
> http://onlinelibrary.wiley.com/doi/10.1002/evan.21311/abstract
>
> The status of Homo heidelbergensis (Schoetensack 1908)
> Chris Stringer 2012
> The species Hheid is central to many discussions about recent human
> evolution:
> - for some workers, it was the LCA for the subsequent spp Hs & Hn,
> - others regard it as only a European form, giving rise to Hn.
> Following the impact of recent genomic studies indicating hybridization
> between Hs & both Hn & "Denisovans", the status of these as separate taxa
> is now under discussion.
> Accordingly, clarifying the status of Hheid is fundamental to the debate
> about modern human origins. © 2012 Wiley Periodicals, Inc.
>


[quote]
The concept of Homo heidelbergensis remains at the center
of such discussions, as this species represents the probable
ultimate ancestor of these three daughter allotaxa: sapiens,
neanderthalensis, and Denisovans.


________________________________





> (we can't say much sensible on this IMO, unless we can isolate DNA from
> "heidelb." fossils  --mv)
>

#59526 From: Jack Barnes <teamyin@...>
Date: Thu Jun 21, 2012 4:05 pm
Subject: Homo heidelbergensis
needninfo
Send Email Send Email
 
HH and HN are just slightly domesticated versions of the first homo that
dispersed throughout eurasia.  Because it was in colder climates it retained its
natural state longer.  Homo erectus dispersed from Northeast Asia and spread
throughout Eurasia 2.4 to 1.8 mya.  Consider it's dispersal as a southern
coastal route to Africa and a northern natural dispersal of individual family
groups.

Homo erectus then entered Africa and was transformed by the savannah into our
current modern and juvenile human body plan.  There is no doubt of this.   Man
did not come from Africa precisely because there were so many hominids in
Africa. Our LCA went to Africa and became two or three different versions of
chimpanzee.  Africa is a garbage dump of ancient primate genes.

Think logically!!  Our foot, brain, hands, nose and skin occurred In the
complete absence of every single ancient primate.  Only pure vertical gene
transfer.

Humans came from a human shaped ape that swam, ran bipedally and owned territory
as an individual.  Both male and female needed to be impressive and hence the
reduced sexual dimorphism.

The cranial vault is very very different from a sagittal crest as seen in the
apiths.   The idea the apiths in Africa are in our line is actually a joke and
one day will be realized that it is the most serious scientific blunder of all
time.

-Jack



Via IPhone


On Jun 21, 2012, at 8:42 AM, "dons3148" <dons3148@...> wrote:

>
>
> --- In AAT@yahoogroups.com, Marc Verhaegen <m_verhaegen@...> wrote:
> >
> > http://onlinelibrary.wiley.com/doi/10.1002/evan.21311/abstract
> >
> > The status of Homo heidelbergensis (Schoetensack 1908)
> > Chris Stringer 2012
> > The species Hheid is central to many discussions about recent human
> > evolution:
> > - for some workers, it was the LCA for the subsequent spp Hs & Hn,
> > - others regard it as only a European form, giving rise to Hn.
> > Following the impact of recent genomic studies indicating hybridization
> > between Hs & both Hn & "Denisovans", the status of these as separate taxa
> > is now under discussion.
> > Accordingly, clarifying the status of Hheid is fundamental to the debate
> > about modern human origins. © 2012 Wiley Periodicals, Inc.
> >
>
> [quote]
> The concept of Homo heidelbergensis remains at the center
> of such discussions, as this species represents the probable
> ultimate ancestor of these three daughter allotaxa: sapiens,
> neanderthalensis, and Denisovans.
>
> ________________________________
>
> > (we can't say much sensible on this IMO, unless we can isolate DNA from
> > "heidelb." fossils --mv)
> >
>
>


[Non-text portions of this message have been removed]

#59527 From: c.h.engelbrecht@...
Date: Thu Jun 21, 2012 4:36 pm
Subject: Aquarboreal apes - the return of Tarzan and Jane?
christianeng...
Send Email Send Email
 
I'm just gonna share a thought I can't get out of my head these days. I'm not
offering a scientific argument at all here, just an image or something.

http://users.ugent.be/~mvaneech/OP%20Verhaegen%20final%20styled.doc.pdf

Marc V. et al conclude in their variation of Hardy & Morgan's 'aquatic ape' that
humans originally evolved in flooded woodland, and have coined the term
'aquarboreal apes' for its sake. I have to say that I'm still personally
confused about what that's based on, but it seems to match the contemporary
flora and fauna associated with most African hominids, eg. Australopithecus,
etc., at least to my understanding. Most of those old East and South African
fossils have been found along with fossilizations of animal and plant species,
that clearly indicates a wooded area and not grassland (and those hominids are
lodged in then coastal deposits, but not that it's a finite aquatic argument,
'cause species just fossilize much easier in such deposits).

Ok, so we might've originally evolved in flooded woodland, seasonally or all
year flooded. Not on grasslands or the current 'mosaic' variation, and not
necessarily along ocean or river coasts, at least originally (or though
Verhaegen lists the Tethys Sea as a possible region for semi-aquatic hominids,
am I right?). It's a valid possibility and seems supported by fossil evidence.

Then my head for some reason switches to the entertainment industry, and
specifically those old Tarzan features from the 1930's with Johnny Weissmuller
and Maureen O'Sullivan. No, hear me out. This fictional Tarzan fella is still a
term for the archetype noble savage human being, a 1912 author's image on our
animal origin, originally in the wake of Darwin's works. (Some even see Tarzan
and his mate Jane as a Darwinian variation of the Biblical Genesis with Tarzan
and Jane as a sort of Adam and Eve, the author Burroughs being an evolutionist,
but what ever).

This character became so popular that we probably all grew up with Weissmuller's
peculiar yell in our ears. Then through the 20th century, you could say that the
Tarzan image moved from the jungle to the grasslands for a while (because the
key fossils are found on what today is the African Savannah), while Elaine
Morgan's contributions insisted to include the image of Jane (and later "Boy")
on equal footing, while also moving this representational family down to water's
edge.
But reading Verhaegen et al now, I just can't help but think that 'Tarzan and
Jane of the jungle' might be making a comeback. It also puzzles me a bit (and
this is not a scientific argument at all, it may be completely random), that in
this popular Weissmuller-version of this scenario, Hollywood looked around for a
1930's man to epitomize this mind image of the original (white) ape man. And for
some reason, they chose an Olympic swimmer. And also in some of these old films,
there are these really long segments showing the characters swimming about in
their perceived jungle paradise. I mean, this aquatic ape "nonsense" were 30
years away in being presented by Hardy, and yet these Hollywood producers
somewheres in their reptilian brains coupled the idea of an original paradise
both with climbing trees and ... swimming.

http://www.youtube.com/watch?v=QMj5Ztme-ZI

Anyway, I just find that a little puzzling in this context. This jungle image is
basically the first conceived one of our animal origin after the Darwinian
breakthrough, and with the Burroughs/Hollywood image of humanity's 'original
paradise' in the African jungle, coupled with the Hardy, Morgan and Verhaegen
contributions, it might still not be too far off.

What ever. It's just a movie.

#59528 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 5:31 pm
Subject: Re: Aquarboreal apes - the return of Tarzan and Jane?
aquape
Send Email Send Email
 
:-D   Very beautiful, thanks a lot, some comments between brackets.

We have to discern schematically IMO:
- hominoid ("ape") evolution: Mio-Pliocene in swamp forests: peri-Tethys,
aquarboreal, climbing-vertic.floating?wading, predom.herbivorous, vertical,
below-branch, central spine, very broad thorax & breast-bone, lateral
arms...
- Homo ("human") evolution = AAT: Pleistocene coasts (& rivers): Ice Ages
2-0 Ma, littoral, Old World coasts, diving-backfloating, +-no climbing,
predom.shellfish, larger brain, heavy skeleton, flat skull, external nose,
flat femora...

--marc

I'm just gonna share a thought I can't get out of my head these days. I'm
not offering a scientific argument at all here, just an image or something.
http://users.ugent.be/~mvaneech/OP%20Verhaegen%20final%20styled.doc.pdf
Marc V. et al conclude in their variation of Hardy & Morgan's 'aquatic ape'
that humans originally evolved in flooded woodland,(Miocene hominoids since
at least c 20 Ma in very densely vegetated swamp forest I'd think --mv) and
have coined the term 'aquarboreal apes'(the term was coined by Marcel
Williams --mv) for its sake. I have to say that I'm still personally
confused about what that's based on,(I'll send you our recent paper on
aquarborealism --mv) but it seems to match the contemporary flora and fauna
associated with most African hominids, eg. Australopithecus, etc., at least
to my understanding.(Pliocene apiths in swamp forests, Pleistocene apiths in
more open wetlands IMO ‹mv) Most of those old East and South African fossils
have been found along with fossilizations of animal and plant species, that
clearly indicates a wooded area and not grassland (and those hominids are
lodged in then coastal deposits, but not that it's a finite aquatic
argument, 'cause species just fossilize much easier in such deposits).
Ok, so we might've originally evolved in flooded woodland, seasonally or all
year flooded. Not on grasslands or the current 'mosaic' variation, and not
necessarily along ocean or river coasts, at least originally (or though
Verhaegen lists the Tethys Sea as a possible region for semi-aquatic
hominids, am I right?  (see above: hominoids vs Homo --mv) ). It's a valid
possibility and seems supported by fossil evidence.
Then my head for some reason switches to the entertainment industry, and
specifically those old Tarzan features from the 1930s with Johnny
Weissmuller and Maureen O'Sullivan. No, hear me out. This fictional Tarzan
fella is still a term for the archetype noble savage human being, a 1912
author's image on our animal origin, originally in the wake of Darwin's
works. (Some even see Tarzan and his mate Jane as a Darwinian variation of
the Biblical Genesis with Tarzan and Jane as a sort of Adam and Eve, the
author Burroughs being an evolutionist, but what ever).
This character became so popular that we probably all grew up with
Weissmuller's peculiar yell in our ears. Then through the 20th century, you
could say that the Tarzan image moved from the jungle to the grasslands for
a while (because the key fossils (no! Lucy or Taung are no human ancestors,
besides, it's now known that they're not found in dry savanna, but along
rivers, well-wooded  --mv) are found on what today is the African Savannah),
while Elaine Morgan's contributions insisted to include the image of Jane
(and later "Boy") on equal footing, while also moving this representational
family down to water's edge.
But reading Verhaegen et al now, I just can't help but think that 'Tarzan
and Jane of the jungle' might be making a comeback.  It also puzzles me a
bit (and this is not a scientific argument at all, it may be completely
random), that in this popular Weissmuller-version of this scenario,
Hollywood looked around for a 1930s man to epitomize this mind image of the
original (white) ape man. And for some reason, they chose an Olympic
swimmer. And also in some of these old films, there are these really long
segments showing the characters swimming about in their perceived jungle
paradise. I mean, this aquatic ape "nonsense" were 30 years away in being
presented by Hardy, and yet these Hollywood producers somewheres in their
reptilian brains coupled the idea of an original paradise both with climbing
trees and ... swimming.
http://www.youtube.com/watch?v=QMj5Ztme-ZI
Anyway, I just find that a little puzzling in this context. This jungle
image is basically the first conceived one of our animal origin after the
Darwinian breakthrough, and with the Burroughs/Hollywood image of humanity's
'original paradise' in the African jungle, coupled with the Hardy, Morgan
and Verhaegen contributions, it might still not be too far off.  What ever.
It's just a movie.




[Non-text portions of this message have been removed]

#59529 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 5:38 pm
Subject: Teilhardina belgica
aquape
Send Email Send Email
 
New postcranial elements for the earliest Eocene fossil primate
Teilhardina belgica
Daniel L Gebo, Thierry Smith & Marian Dagosto 2012 JHE press

T.belgica is one of the most primitive fossil primates known to date, and
the earliest haplorhine with associated postcranials ...
Here we describe newly discovered postcrania.
Its estimated body mass is 30-60 g (cf mouse lemur).
Its hindlimbs suggest frequent & forceful leaping with
- excellent foot mobility,
- excellent grasping capabilities.

It exhibits critical primate postcranial synapomorphies, eg,
- grasping hallux,
- tall knee,
- nailed digits.

This anatomical pattern & behavioral profile is similar to what has been
inferred before for other omomyids & adapiforms.
The most unusual feature is its elongated middle phalanges (most likely
manual phalanges):
this early primate had very long fingers similar to those of living
tarsiers.

(for grasping branches as well as (with fingers spread) prey  --mv)

#59530 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 5:47 pm
Subject: small hard particles: flat micro-tecture --- large hard items: larger tooth relief
aquape
Send Email Send Email
 
Teasing apart the contributions of hard dietary items on 3D dental
microtextures in primates
Ivan Calandra, Ellen Schulz, Mona Pinnow, Susanne Krohn & Thomas M Kaiser
2012 JHE press

3D dental micro-texture analysis is a powerful tool for reconstructing the
diets of extinct primates.
This method is based on the comparison of fossils with extant spp of known
diet.
The diets of primates are highly diversified: fruits, seeds, grass, tree
leaves, bark, roots, tubers & animal resources.
Fruits remain the main component in the diets of most primates.

Is the proportion of fruit consumed correlated with dental microtexture?
2 methods of micro-texture analysis (scale-sensitive fractal analysis SSFA
& Dental Areal Surface Texture Analysis DASTA) were applied to specimens
of 8 primate spp (Alouatta seniculus, Gorilla gorilla, Lophocebus
albigena, Macaca fascicularis, Pan troglodytes, Papio cynocephalus, Pongo
abelii, Theropithecus gelada).
  These spp largely differ in the mean annual proportion of fruit (from 0
to 90 %) in their diet, as well as in their consumption of other hard
items (seeds, bark, insect cuticles) & abrasive plants.

We find the complexity & heterogeneity of textures (SSFA) to correlate
with the proportion of fruits consumed.
Textural fill volume (SSFA) indicates the proportion of both fruits &
other hard items processed.
Anisotropy (SSFA) relates to the consumption of abrasive plants: grass &
other monocots.
ISO parameters valley height, root mean square height, material volume,
density of peaks & closed hill & dale areas (DASTA) describe the
functional interaction between food
items & enamel facets during mastication.

- The shallow plastic deformation of enamel surfaces induced by small hard
particles (eg, phytoliths, dust) results in flat micro-texture relief.
- The brittle, deep fracture caused by large hard items (eg, hard seeds)
creates larger relief.

#59531 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 5:50 pm
Subject: The impact of learning on sexual selection and speciation
aquape
Send Email Send Email
 
The impact of learning on sexual selection and speciation
Machteld N Verzijden cs 2012 TREE press

Learning is widespread in nature, occurring in most animal taxa & in
several different ecological contexts:
it might play a key role in evolutionary processes.

Here, we review the accumulating empirical evidence for the involvement of
learning in mate choice & the consequences for sex.selection &
reproductive isolation.
We distinguish 2 broad categories:
- learned mate preferences &
- learned traits under mate selection (eg, bird song).

We point out that the context of learning (how & when learning takes
place) often makes a crucial difference to the predicted evolutionary
outcome.
Factors causing biases in learning, and when one should expect the
evolution of learning itself, are also explored.

#59532 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 6:05 pm
Subject: Re: Homo heidelbergensis
aquape
Send Email Send Email
 
Jack:
HH and HN are just slightly domesticated versions of the first Homo that
dispersed throughout eurasia.  Because it was in colder climates it
retained its natural state longer.  H.erectus dispersed from NE.Asia and
spread throughout Eurasia 2.4 to 1.8 Ma.  Consider its dispersal as a
southern coastal route to Africa and a northern natural dispersal of
individual family groups.


Jack, AFAICS these are unproven ideas of yours.
- The first erectus-like fossils are found in Kenya, Georgia & Java c 1.8
Ma. They got there not "throughout Eurasia", but along the Indian Ocean,
African & Mediterranean coasts.
- Colder climates?  European Homo appears in northern regions (England...)
during (warmer) interglacials AFAWK (Stringer).

Homo erectus then entered Africa and was transformed by the savannah into
our current modern and juvenile human body plan.  There is no doubt of
this.

??
It's ridiculous nonsense, Jack!
Savannah mammals are not furless, are not fat, often don't sweat at all,
have high renal concentration capacities, don't need much water etc.etc.
We never were savanna mammals.  The few hman populations that today live
there only recently (after c 100 kq?) got there. Most humans still lived
at coasts & rivers.

M.Verhaegen 1987 Nature 325:305-306
"Origin of hominid bipedalism"
Sinclair et al.(1) believe that human bipedalism arose in scavenging
hominid ancestors that had to carry their children while following
migrating savanna ungulates but this seems highly improbable.
There was no empty niche of migrating scavengers to be occupied by hominid
ancestors. Not only vultures, but aso canid, felid and hyaenid carnivores
were much better preadapted for such a niche. They possessed sharp beaks
or long canine teeth and did not need to carry stones for cutting
carcasses. Moreover, the bipedal way of locomotion - whether fast of slow
- is inefficient and costly (2,3).
Another argument against the migrating hypothesis in particular and the
savannah theory of human evolution in general is that it is highly
unlikely that hominid ancestors ever lived in the savannas. Man is the
opposite of a savanna inhabitant. Humans lack sun-reflecting fur (4) but
have thermo-insulative subcutaneous fat layers, which are never seen in
savanna mammals. We have a water- and sodium-wasting cooling system of
abundant sweat glands, totally unfit for a dry environment (5). Our
maximal urine concentration is much too low for a savanna-dwelling mammal
(6). We need much more water than other primates, and have to drink more
often than savanna inhabitants, yet we cannot drink large quantities at a
time (7-8). The fossils of our hominid ancestors or relatives are always
found in water-rich environments.
It is difficult to understand why most anthropologists keep believing in
the savanna theory (possibly because it goes back to Darwin), or why so
many anthropologists keep
trying to seek the most improbable reasons for bipedalism, while they
should know there are much better explanations (9-11).




Jack:
Man did not come from Africa precisely because there were so many hominids
in Africa. Our LCA went to Africa and became two or three different
versions of chimpanzee.  Africa is a garbage dump of ancient primate genes.
Think logically!!  Our foot, brain, hands, nose and skin occurred In the
complete absence of every single ancient primate.  Only pure vertical gene
transfer.
Humans came from a human shaped ape that swam, ran bipedally and owned
territory as an individual.  Both male and female needed to be impressive
and hence the reduced sexual dimorphism.
The cranial vault is very very different from a sagittal crest as seen in
the apiths.   The idea the apiths in Africa are in our line is actually a
joke and one day will be realized that it is the most serious scientific
blunder of all time.  -Jack


Yes, of course, apiths are not our ancestors, but that has nothing to do
with what you're saying above AFAICS.

--marc

______


> > http://onlinelibrary.wiley.com/doi/10.1002/evan.21311/abstract
> >
> > The status of Homo heidelbergensis (Schoetensack 1908)
> > Chris Stringer 2012
> > The species Hheid is central to many discussions about recent human
> > evolution:
> > - for some workers, it was the LCA for the subsequent spp Hs & Hn,
> > - others regard it as only a European form, giving rise to Hn.
> > Following the impact of recent genomic studies indicating hybridization
> > between Hs & both Hn & "Denisovans", the status of these as separate
>taxa
> > is now under discussion.
> > Accordingly, clarifying the status of Hheid is fundamental to the
>debate
> > about modern human origins. © 2012 Wiley Periodicals, Inc.
> >
>
> [quote]
> The concept of Homo heidelbergensis remains at the center
> of such discussions, as this species represents the probable
> ultimate ancestor of these three daughter allotaxa: sapiens,
> neanderthalensis, and Denisovans.
>
> ________________________________
>
> > (we can't say much sensible on this IMO, unless we can isolate DNA from
> > "heidelb." fossils --mv)
> >
>
>

#59533 From: Heather Twist <HeatherTwist@...>
Date: Thu Jun 21, 2012 7:06 pm
Subject: Re: Aquarboreal apes - the return of Tarzan and Jane?
heathertwist2
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The thing that strikes me about Tarzan (and "The Family Robinson") is now
reasonable it seems, at some level, that a family could live in the jungle
like that. I mean, watching Tarzan swing, swim, and fight alligators, just
doesn't seem outlandish, and probably most boys (and girls) did their
version of the rope swing. Maybe into the swimming pool or lake, if they
had one. And a treehouse. What kid doesn't like to climb trees? Well, if
there isn't a tree, most playgrounds have jungle gyms. One of the most
popular attractions at Disneyland, for decades, has been "The Swiss Family
Robinson Treehouse" (which still exists, though it's been rebranded with
some later movie).

Watching the Maasai out herding cows though ... doesn't appeal to most
people. It looks hot and dry and boring. I can't recall a movie about some
stranded person surviving in the grassland, much less raising a family.
There are the cowboy movies, but most of the fun scenes are in saloons and
they were always looking for a river to water the horses. The one movie
that comes to mind about Kansas is The Wizard of Oz, and Dorothy's big
thing was to get OUT of Kansas. The one thing that brought her back was her
friends and family, but they never made the case that Kansas was a great
place to live.


On Thu, Jun 21, 2012 at 9:36 AM, <c.h.engelbrecht@...> wrote:

> **
>
>
> I'm just gonna share a thought I can't get out of my head these days. I'm
> not offering a scientific argument at all here, just an image or something.
>
> http://users.ugent.be/~mvaneech/OP%20Verhaegen%20final%20styled.doc.pdf
>
> Marc V. et al conclude in their variation of Hardy & Morgan's 'aquatic
> ape' that humans originally evolved in flooded woodland, and have coined
> the term 'aquarboreal apes' for its sake. I have to say that I'm still
> personally confused about what that's based on, but it seems to match the
> contemporary flora and fauna associated with most African hominids, eg.
> Australopithecus, etc., at least to my understanding. Most of those old
> East and South African fossils have been found along with fossilizations of
> animal and plant species, that clearly indicates a wooded area and not
> grassland (and those hominids are lodged in then coastal deposits, but not
> that it's a finite aquatic argument, 'cause species just fossilize much
> easier in such deposits).
>
> Ok, so we might've originally evolved in flooded woodland, seasonally or
> all year flooded. Not on grasslands or the current 'mosaic' variation, and
> not necessarily along ocean or river coasts, at least originally (or though
> Verhaegen lists the Tethys Sea as a possible region for semi-aquatic
> hominids, am I right?). It's a valid possibility and seems supported by
> fossil evidence.
>
> Then my head for some reason switches to the entertainment industry, and
> specifically those old Tarzan features from the 1930's with Johnny
> Weissmuller and Maureen O'Sullivan. No, hear me out. This fictional Tarzan
> fella is still a term for the archetype noble savage human being, a 1912
> author's image on our animal origin, originally in the wake of Darwin's
> works. (Some even see Tarzan and his mate Jane as a Darwinian variation of
> the Biblical Genesis with Tarzan and Jane as a sort of Adam and Eve, the
> author Burroughs being an evolutionist, but what ever).
>
> This character became so popular that we probably all grew up with
> Weissmuller's peculiar yell in our ears. Then through the 20th century, you
> could say that the Tarzan image moved from the jungle to the grasslands for
> a while (because the key fossils are found on what today is the African
> Savannah), while Elaine Morgan's contributions insisted to include the
> image of Jane (and later "Boy") on equal footing, while also moving this
> representational family down to water's edge.
> But reading Verhaegen et al now, I just can't help but think that 'Tarzan
> and Jane of the jungle' might be making a comeback. It also puzzles me a
> bit (and this is not a scientific argument at all, it may be completely
> random), that in this popular Weissmuller-version of this scenario,
> Hollywood looked around for a 1930's man to epitomize this mind image of
> the original (white) ape man. And for some reason, they chose an Olympic
> swimmer. And also in some of these old films, there are these really long
> segments showing the characters swimming about in their perceived jungle
> paradise. I mean, this aquatic ape "nonsense" were 30 years away in being
> presented by Hardy, and yet these Hollywood producers somewheres in their
> reptilian brains coupled the idea of an original paradise both with
> climbing trees and ... swimming.
>
> http://www.youtube.com/watch?v=QMj5Ztme-ZI
>
> Anyway, I just find that a little puzzling in this context. This jungle
> image is basically the first conceived one of our animal origin after the
> Darwinian breakthrough, and with the Burroughs/Hollywood image of
> humanity's 'original paradise' in the African jungle, coupled with the
> Hardy, Morgan and Verhaegen contributions, it might still not be too far
> off.
>
> What ever. It's just a movie.
>
>
>



--
Heather Twist
http://eatingoffthefoodgrid.blogspot.com/


[Non-text portions of this message have been removed]

#59534 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 10:04 pm
Subject: OH hominids found amid sedges
aquape
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Fossil sedges, macroplants, and roots from Olduvai Gorge, Tanzania
Marion K Bamford 2012 JHE press

A variety of macro-plants has been recorded & collected from the eastern
paleo-lake margin of Olduvai Gorge from Upper Bed I & Lower Bed II
¡ã1.7¡V1.85 Ma.
The plant groups represented are sedges, grasses & woody & herbaceous
dicotyledons.
Most of these plants are fragmented, but the roots are in situ.
The modes & quality of preservation are very variable.
Silicification is the dominant type of preservation; it ranges from high
quality faithful replacement of cells resulting in silicified wood & sedge
culms identifiable on the basis of their internal anatomy, to poor-quality
bio-tubes lacking internal anatomy or external features that prevent
assignment to a specific plant or invertebrate origin.
In between this range are silicified roots & grass culms identified by
their external anatomy, & leaf & stem impressions.
Interpretation of the paleo-ecology is limited by the quality of
preservation.
The in situ root horizons are useful for recognizing paleo-surfaces.
The best quality preservation where internal anatomy is preserved occurs
at HWK-E & MCK, localities that are in the middle of the fault
compartments, so the vegetation can be reconstructed for these sites.
Some sedge culms are described, illustrated & identified as possible spp
of Cyperus, Fuirena & Schoenoplectus.

#59535 From: Marc Verhaegen <m_verhaegen@...>
Date: Thu Jun 21, 2012 10:48 pm
Subject: Re: "heidelbergensis"
aquape
Send Email Send Email
 
http://onlinelibrary.wiley.com/doi/10.1002/evan.21311/full








http://onlinelibrary.wiley.com/doi/10.1002/evan.21311/abstract

The status of Homo heidelbergensis (Schoetensack 1908)
Chris Stringer 2012
The species Hheid is central to many discussions about recent human
evolution:
- for some workers, it was the LCA for the subsequent spp Hs & Hn,
- others regard it as only a European form, giving rise to Hn.
Following the impact of recent genomic studies indicating hybridization
between Hs & both Hn & "Denisovans", the status of these as separate taxa
is now under discussion.
Accordingly, clarifying the status of Hheid is fundamental to the debate
about modern human origins. © 2012 Wiley Periodicals, Inc.

(we can't say much sensible on this IMO, unless we can isolate DNA from
"heidelb." fossils  --mv)

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