New finds at Dmanisi

[Rokcet Scientist]

BBC: Wednesday, 19 September 2007, 21:51 GMT

Georgia clues to human origins

Femur at Dmanisi. Image: Georgia National Museum

The finds shed light on a key stage in human evolution
A team of scientists working in Georgia has unearthed the remains of four human-like creatures dating to 1.8 million years ago.

In the journal Nature, the researchers outline details of the partial skeletons uncovered in a Medieval town.

The bones reveal a mixture of primitive and advanced features, team leader David Lordkipanidze explained.

These early hominids may have been among the first to leave Africa to colonise the rest of the world.

Discovered in the early 1990s, the Dmanisi site has proved a rich source of remains and artefacts from the dawn of the Pleistocene period.

Studying the various skulls and jaws has given scientists important information about the early species that lived here.

But, until now, they had little information about the rest of the skeleton.

Ancient pioneers

The remains uncovered at the town of Dmanisi consist of the partial skeleton of an adolescent individual associated with a skull, and the "post-cranial" remains of three adults.

David Lordkipanidze with fossil. Image: Georgia National Museum
The upper limbs are relatively primitive
The specimens are among the oldest hominids to be found outside Africa.

In many respects, the well-preserved fossils resemble Homo erectus, a species from the genus Homo that first appeared in Africa some two million years ago and quickly spread throughout Europe and much of Asia.

They have remarkably human-like spines and lower limbs that would have been well suited for long distance travel. Their feet had well-developed arches.

An apparently small difference in the size of males and females also puts them in the same company as Homo erectus and Homo sapiens.

However, they also have relatively small brains and primitive upper limbs, traits which they share with the earlier Homo habilis, and even with the more primitive Australopithecus, which first appeared in Africa some four million years ago.

http://news.bbc.co.uk/1/hi/sci/tech/7003502.stm

[Beagle]

Good article RS. I read recently that there is some conjecture that this human left Africa, and in isolation, evolved quickly into H. Erectus, which then traveled back into Africa. Only time will tell on that one. Nice find.

[AD]

Hi RS and Beagle...

Thanks for that posting! Dmanisi is certainly one of the more important finds in recent years - hominins in an apparently sizeable community quite a distance from Africa about a million years before they were supposed to be anywhere else. So they are thought to have returned to Africa? Why would an obviously adventurous creature necessarily do that? And given a few extra hundred thousand years, proto-humans, even with smaller brain cases, could have covered a lot of territory, hypothetically even across Asia and into North America. There is Alan Thorne's "regional continuity" hypothesis that homo erectus spread to all reachable areas of the planet and then evolved locally into the various races of homo sapiens. While this is a bit hard to swallow whole, I really have to consider something like this in contemplating the huge quantity of verified carved stones incorporating simple apparently animistic/shamanistic bird and bird-human imagery looking very much the same in Africa, Europe, North America, and Australia. (Some of you probably recall my earlier ravings on this subject in various threads in this forum.)

Regards, Alan
http://www.daysknob.com

[Minimalist]

You know.....if you stick with Darwin's idea of a group needing to be isolated in order to evolve....then it really makes more sense that groups which were out of the mainstream doing the evolving rather than the groups which stayed behind.

I've got to roll this around in my head a bit more. Right now, the Yankees are on, though.

[Forum Monk]

This article on Dmanisi was published in 2005 and explains in greater detail some thoughts on what the skull finds may reveal:
http://news.nationalgeographic.com/news ... skull.html

There is Alan Thorne's "regional continuity" hypothesis that homo erectus spread to all reachable areas of the planet and then evolved locally into the various races of homo sapiens. While this is a bit hard to swallow whole, I really have to consider something like this in contemplating the huge quantity of verified carved stones incorporating simple apparently animistic/shamanistic bird and bird-human imagery looking very much the same in Africa, Europe, North America, and Australia.

Earlier, on another thread, I asked it the "out of africa" hypothesis was the prevailing consensus on this board. While I have not yet drawn such a conclusion, myself, I think certain aspects of the "multiregional" hypothesis may have merit, especially considering the evolution of the tools and technologies as well as the morphologies of skeletal remains. OOA is primarily based upon genetic evidence if I am not mistaken. In addition, there are several flavors of OOA including some variations of the replacement hypotheses which I have not seen debated much on this board.

[daybrown]

<You know.....if you stick with Darwin's idea of a group needing to be isolated in order to evolve....then it really makes more sense that groups which were out of the mainstream doing the evolving rather than the groups which stayed behind. >
That's just was Sass, in "the Children of the Ice Age" says. It'd be useful to have a regional climate reconstruction to consider.

I've read that at some point, there was grassland all the way across North Africa and on up past the Levant to the Aral Sea region. But during the ice ages, prolly colder, and demanding new technologies to survive the winter.

the mention of the well developed arches suggests long distance Nomads running to manage their livestock. Like the Masai.

[Minimalist]

I'm suspicious of OOA, Monk. If for no other reason that The Club seems willing to endorse it.

[Rokcet Scientist]

Yup. It's the finches all over.

[Beagle]

The period of time between Dminisi man and the hypothesized H. Erectus seafaring is a million years. I sometimes have to pause and remind myself of what a chunk of time that is. It's small wonder that there is little agreement in science as to what happened during that span of time.

[Beagle]

Hi RS and Beagle...

Thanks for that posting! Dmanisi is certainly one of the more important finds in recent years - hominins in an apparently sizeable community quite a distance from Africa about a million years before they were supposed to be anywhere else. So they are thought to have returned to Africa? Why would an obviously adventurous creature necessarily do that? And given a few extra hundred thousand years, proto-humans, even with smaller brain cases, could have covered a lot of territory, hypothetically even across Asia and into North America. There is Alan Thorne's "regional continuity" hypothesis that homo erectus spread to all reachable areas of the planet and then evolved locally into the various races of homo sapiens. While this is a bit hard to swallow whole, I really have to consider something like this in contemplating the huge quantity of verified carved stones incorporating simple apparently animistic/shamanistic bird and bird-human imagery looking very much the same in Africa, Europe, North America, and Australia. (Some of you probably recall my earlier ravings on this subject in various threads in this forum.)

Regards, Alan
http://www.daysknob.com

Hi Alan. I am a multi-regionalist of many years, although I suspect that the actual truth may be different from anything proposed so far. As you note, we're pretty sure that Erectus, once he had evolved, traveled to every corner of the planet, even to Africa.

There were a number of different kinds of humans but after a few million years of gene swapping we're down to just us Sapiens, who in different regions may still harbor the genes and traits of earlier types of humans.

That's been my viewpoint for some time. Eventually the geneticists will have the answers, but they'll have to unravel all the "junk" DNA as well, so I'm not holding my breathe.

[Digit]

There is a difference Min in the idea of man evolving in Africa and developing in Africa. The current evidence is indeed that Homo has African origins, but we already know that HSN, for example arose elsewhere.
The Chinese argument is that man arose in Africa but developed in Asia, agreed there is a political point scoring system involved here, but that doen't mean it is wrong

[Minimalist]

That's multi-regionalism and, like Beags, I think it has much in its favor.

I've never been comfortable with OOAs apparent inability to explain different racial characteristics which, as has been noted before, include skeletal changes as well as skin color.

Something is not right in Denmark.

[Beagle]

http://news.yahoo.com/s/nm/20070919/sc_ ... 7x8O4E1vAI

The remains shed light on a little-understood but critical period in human evolution -- the transition from the more ape-like creatures known as australopithecines to the genus Homo, of which modern humans are a member.

The spines and lower limbs found at the Dmanisi site appear very much like modern humans, suggesting these individuals, which walked fully upright, were highly capable of long-distance treks, the researchers said.

But other aspects of the skeletons had more archaic characteristics. The arms were more like australopithecines than people, and the primitive skulls encased relatively small brains. Their simple stone tools also are less advanced than one might have expected, the researchers said.

They described the remains as "a surprising mosaic" of primitive and modern features.

"These are the earliest humans found outside of Africa. This is the time when our genus spread outside of Africa," David Lordkipanidze of the Georgian National Museum, who led the research, said in a telephone interview. "Their heads are primitive. Their legs are very human-like."

Scientists had previously described skulls found at the site, but in recent years found far more extensive remains of the skeletons of these creatures, giving them a more detailed understanding of these denizens of early human history.

DANGER LURKS

Also found at the site were remains of other animals that lived alongside these human ancestors, including saber-toothed cats that might have feasted on these human ancestors, primitive elephants, ostriches and giraffes.

Reuters joins in with another article today.

[gunny]

Curious about "just us sapiens". The I think monk, from Belgium of Holland , that classified all things at the time would put a third, or fourth description on an animal or butterfly when it differed from the prime species. Humans differ significantly from the butterfly with different colored wings with different species trailing names. Were we trying to be polite by not adding additional descriptions to homo sapien sapien for the blacks, asians, pygmy, etc?

[Beagle]

I wasn't trying to be polite gunny, just accurate. What you are describing are the races of man. But those descriptions don't take a lot of things into account. It seems, for instance, that a large portion of the Indian sub-continent is populated by caucasians. But they are not white skinned. Makes for confusion in this case I think.

We've never shied away from a discussion of racial differences, I just didn't think it applied here.