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02-10-2009, 14:11   #1
Galvasean
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Ardi - Missing Link revised

It's been a long time coming, but regular posters of this forum will be delighted to know that the first major analysis of 'Ardi' (Ardipithecus ramidus) has been released.
The findings are exremely important as it reveals 'Ardi' to be the earliest known upright ape, living some 1 million years before the famous 'Lucy' (Australopithecus afarensis). 'Ardi' would have been able to walk and probably even run upright, while retaining the ability to climb around in trees, albeit slowly. One thing which has been ruled out in 'Ardi' is knuckle walking, like that of modern apes such as gorillas and chimps. 'Ardi' also had human like canines, again, unlike the aforementioned apes. These two factors mean that the previously held assumption that human ancestors of the time would have looked and behaved like modern chimps to be wrong.

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A DETAILED ANALYSIS of human-like fossils discovered in Ethiopia has taken mankind back in time, a million years closer to the “missing link” ancestor we share with the great apes. In the process, scientists have been forced to rethink human evolution and what the missing link must have looked like.

It overturns the widely held view that chimpanzees and gorillas must be typical of the look and behaviour of our shared ancestors. The research proves that the modern apes are very poor models for the last common ancestor, opening up a whole new perspective on the separate tracks taken by ape and human evolution. A staggering amount of data has come from an intensive study, lasting several years, of a human-like or hominid animal called Ardipithecus ramidus.
Full article here.

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02-10-2009, 15:28   #2
Goduznt Xzst
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If you sign up for free you can access the research articles on Ardi here:

http://www.sciencemag.org/ardipithecus/
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02-10-2009, 23:13   #3
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The Discovery Channel will soon be showing a program called 'Discovering Ardi'.
Watch this space.
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04-10-2009, 12:10   #4
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Amazing stuff. Only read the Ir Times article. I'm always astonished at the conclusions they come to on what seems to be little evidence. From no (little) canine teeth to, that means that pair bonding was in place, rather than the Alpha male gets all the females & the rest of the males get what they can on the sly.

Wondering how the pair-bonding hypothesis stands in relation to the men have to have sex with lots of women to maximise reproductive potential theory (I know they are not exclusive) and how that impacts on modern behaviour (which is constantly justified in terms of what is 'natural')
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04-10-2009, 20:54   #5
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Article on National Geographic on Ardi's sex life. Read at your own peril...

http://news.nationalgeographic.com/n...ssils-sex.html
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05-10-2009, 16:31   #6
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Interesting one alright that shows bipedalism come well before intelligence and tool use. It clearly held serious advantages(considering it's disadvantages). A sexual reason may be possible, but I dunno.

I agree with JuliusCaesar, there does seem to be a lot of extrapolation going on, which is one of the bugbears I have about hominid research. They'll (pretty much rightfully) dismiss the aquatic ape theory, yet go off on wild conjecture of their own on even scanter evidence.

For a start how do they know other canines came from a male? They simply don't. Without a pelvis or near complete skull it could just have been a more robust female within the gender limits of that species. We all know women that are 4"11 and women who are much taller and more robust. That's with the benefit of numbers. If we dug up one of the 4"11 ones in a million years time there's no way we could suggest that all female sapiens were 4'11. It's complete conjecture. Smaller canines could simply be an adaptation to a particular diet.

Much more recently in our history finds in georgia seem to suggest a big dimorphism in the genders of homo erectus, which would suggest that a harem type thing may have been going on there.

I'm not so sure about the pair bonding thing. Even in our own species we're pretty variable in this. Many cultures practice male harem/many wives type arrangements, yet we're considered pair bonding types? I think ones culture informs that theory as much as anything. If a Maasai scientist was asked he may well see the many wives theory as being more valid.

It is an interesting find though that pushes a form of bipedalism much further back. Jusging by the foot anatomy, it does look like an intermediate form too. A "missing link" for bipedalism.
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05-10-2009, 22:46   #7
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The funny thing about bipedalism is we're the only ones now who do it it(feck off if you mention birds) among the apes. It seems to have been an advantageous adaptation and at one point there were many species, seven or more IIRC so far discovered that were out at the same time who were upright walkers of a hominid form. This is pretty much the first time in bipedal and hominid history that there is only one hominid on the planet. Go back 150,000 years and there were three we know of. If the "hobbit" and associated legends are to be believed up to 12000 years ago there was another and the locals say that they even may have lasted until historical times.

I have to say though for all my skeptical take on the interpretation of the finds, this is a monumental discovery in our human ancestry. It's such a pity that it seems to be only a small area in Africa where we can get this stuff. Where elsewhere is more written of our past? That said it's amazing that we even have that, so few are the remains of hominids from any era. From homo habilis on we have places where you damn near have to search for ordinary rocks among the tools of that hominid, yet of them we have so so little and even the association with their tools is a pretty loose one. Turkana boy http://upload.wikimedia.org/wikipedi...urkana_Boy.jpg is probably the most complete skeleton of an early hominid(erectus). He's pretty much more complete than any neandertal skeleton we have. Bloody magnificent looking bugger he is too.

*start of wistful and wishful thinking*....All the talk over the years of "bigfoot" "wildmen" and the "yeti" (even trolls in europe) may be a race memory of the idea of the other bipedal creatures. Interestingly the idea or legends of wildmen do not show up in isolated islands. So no legends in hawaii or new zealand etc. Marco polo said he saw a captured one on his travels. Not a great witness you say, but he was pretty accurate in his zoological descriptions(amazing for his time actually) and he saw the primitive prizewalskis horse long before it was described or accepted by western science. It always fascinated me the idea that maybe, just maybe there may be some still left. Before I get moved to the paranormal forum No less an authority than Dr Jane Goodall is also fascinated by some of the reports of wildmen and behaviour reported and has spoken of her interest more than once

Only recently there was an expedition to Sumatra looking for the Orang Pendek. http://www.extreme-expeditions.com/j...26791866939117 Personally for me the most promising as some good witnesses have reported seeing it. Including an eminent Orang utan field researcher. It's reported not to have feet like a human either more like Ardi. Another detail that intrigues. Nor is it 10foot tall either. God luv me but here's a pic of the footprint. I know I know I'm going to be banned it's from the Sun *hangs head in shame* http://www.thesun.co.uk/sol/homepage...-by-Brits.html

Its only in the early part of the 20th century that the mountain gorilla was finally taken out of the realms of legend and the "Lion killer" chimps of the Congo have only been very recently described this century and little is still known of them. They're much bigger than normal chimps and have saggital crests.

Oh to see an Ardi type creature in the flesh. One helluva rush and strange feeling, so I for one have a little hope that they're not just a race memory and somewhere tonight in some remote place something bipedal may still walk. *end wishful and wistful rant*
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10-10-2009, 16:38   #8
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Interesingly, it appears that Ardipithecus lived in the woods, as opposed to open savanah as had been assumed.
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'On the west we find lots of Ardipithecus fossils and they're associated with a lot of woodland and forest animals,' he said. 'And then there's a break; Ardipithecus and most of the monkeys that live in trees disappear, and grass-eating animals become more abundant.'

The carbon isotope ratios of the Ardipithecus teeth also tell the story of a woodland creature, he said.

'The diet of the Ardipithecus is much more on the woodland and forest side,' he said. 'It's got a little bit more of the grassland ecosystem carbon in its diet than that of a chimpanzee but much less than its fully bipedal savanna-dwelling descendents, the australopithecines.'

This evidence, along with the anatomical studies indicating that Ardipithecus could walk upright but also grasped tree limbs with its feet, suggests that this early hominid took its first steps on two legs in the forest long before it ventured very far into the open grassland, Ambrose said
Full article here:
http://www.sciencecentric.com/news/a...legs-the-woods
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11-10-2009, 15:00   #9
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Thanks for the article links. Fascinating. Of course this isn't the only field in which speculation is rife - archaeology too....and maybe the behavioural sciences
I'm very temped to link this thread with the monogamy discussion on After Hours, where there are amazing 'facts' being propounded about the natural/primitive/historical state of humans, backed up by reference to chimps and bonobos....and very dodgy notions of world history....But that's a different topic altogether!
If only we could Time Travel!
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18-10-2009, 23:09   #10
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Originally Posted by Wibbs View Post
Marco polo said he saw a captured one on his travels. Not a great witness you say, but he was pretty accurate in his zoological descriptions(amazing for his time actually) and he saw the primitive prizewalskis horse long before it was described or accepted by western science.
Damned with faint praise

Just watched the documentary there interesting stuff indeed, it certainly throws most of the previous assumptions of the last common ancestor out the window. What was also very encouraging was the number of African scientists involved in the project, which bodes well for the prospects of making other important discoveries on the Continent in the future.

Last edited by marco_polo; 19-10-2009 at 01:16. Reason: Spelling malfunction
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04-11-2009, 16:53   #11
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Chinese challenge to 'Out of Africa' theory

I got this from the New Scientist website:

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The discovery of an early human fossil in southern China may challenge the commonly held idea that modern humans originated out of Africa.

Jin Changzhu and colleagues of the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, announced to Chinese media last week that they have uncovered a 110,000-year-old putative Homo sapiens jawbone from a cave in southern China's Guangxi province.

The mandible has a protruding chin like that of Homo sapiens, but the thickness of the jaw is indicative of more primitive hominins, suggesting that the fossil could derive from interbreeding.

If confirmed, the finding would lend support to the "multiregional hypothesis". This says that modern humans descend from Homo sapiens coming out of Africa who then interbred with more primitive humans on other continents. In contrast, the prevailing "out of Africa" hypothesis holds that modern humans are the direct descendants of people who spread out of Africa to other continents around 100,000 years ago.

The study will appear in Chinese Science Bulletin later this month.

Out of China?
"[This paper] acts to reject the theory that modern humans are of uniquely African origin and supports the notion that emerging African populations mixed with natives they encountered," says Milford Wolpoff, a proponent of the multiregional hypothesis at the University of Michigan.

Others disagreed. Erik Trinkaus, an anthropologist at Washington University in St Louis, Missouri, questioned whether the find was a true Homo sapiens.

"You need to keep in mind that 'Homo sapiens' for most Chinese scholars is not limited to anatomically modern humans," he says. "For many of them, it is all 'post Homo erectus,' humans."

Chris Stringer of London's Natural History Museum said that it was too early to make far-reaching conclusions. "From the parts preserved, this fossil could just as likely be related to preceding archaic humans, or even to the Neanderthals, who at times seem to have extended their range towards China."

The present analysis of the mandible focused almost exclusively on determining the fossil's age. The researchers said a follow-up study would give a more complete treatment on what exactly the find represents.
There is also a picture of the 110,000-year-old jawbone, which Chinese scientists are saying is from a Homo sapiens:
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04-11-2009, 17:12   #12
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Interesting that it should be unveiled so soon after the African Algeripithecus was proven not to be part of the human ancestry.

PS: In before Wibbs says "I told ya so"

Last edited by Galvasean; 04-11-2009 at 17:15.
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04-11-2009, 19:10   #13
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Just in the door, but I told you so
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04-11-2009, 19:21   #14
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"You need to keep in mind that 'Homo sapiens' for most Chinese scholars is not limited to anatomically modern humans," he says. "For many of them, it is all 'post Homo erectus,' humans."
Forgive me if this is obvious to everyone else, I'm an absolute amateur.

What is a post-erectus human? Is this what people refer to when they are speaking of Heidlbergesensis(sp?) and Cro-Magnon? Were the Homo eretus' in Asia/Europe evolving on similar lines to those in Africa (i.e in a Homo Saipien Direction?)

Also if as this study concludes that Modern Homo Saipiens are a result of inter-breeding between Homo Sapiens from Africa and more primitive Hominids from Europe/Asia, then why are people who have never left Africa, such as the San, practically identical to other humans?

I'm sure all I've said is rife with mistakes in classification, spelling and understanding, but if anyone knows what I'm trying to say could they answer?
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04-11-2009, 19:49   #15
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Originally Posted by yekahs View Post
Forgive me if this is obvious to everyone else, I'm an absolute amateur.

What is a post-erectus human? Is this what people refer to when they are speaking of Heidlbergesensis(sp?) and Cro-Magnon? Were the Homo eretus' in Asia/Europe evolving on similar lines to those in Africa (i.e in a Homo Saipien Direction?)

Also if as this study concludes that Modern Homo Saipiens are a result of inter-breeding between Homo Sapiens from Africa and more primitive Hominids from Europe/Asia, then why are people who have never left Africa, such as the San, practically identical to other humans?

I'm sure all I've said is rife with mistakes in classification, spelling and understanding, but if anyone knows what I'm trying to say could they answer?
Not sure if this tree is the latest classification, but it should be relatively close.



As for the homo sapiens terminology it can be a little confusing, for example some scholars would classify the species Homo Sapiens as having two subspecies Homo Sapiens Neanderthalensis (Neanderthals) and Homo Sapiens Sapiens (Modern humans) others would clasify Homo Sapiens and Homo Neanderthalensis as distinct species. I don't even know which one to use

A relatively unbiased bite-sized introductory page to the competing theories can be found here: http://anthropology.si.edu/HumanOrig.../diversity.htm

Last edited by marco_polo; 04-11-2009 at 20:08.
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