Earliest modern humans?

Researchers find earliest evidence for modern human behavior in South Africa:

"Our findings show that at 164,000 years ago in coastal South Africa humans expanded their diet to include shellfish and other marine resources, perhaps as a response to harsh environmental conditions," notes Marean, a professor in ASU's School of Human Evolution and Social Change. "This is the earliest dated observation of this behavior."

Further, the researchers report that co-occurring with this diet expansion is a very early use of pigment, likely for symbolic behavior, as well as the use of bladelet stone tool technology, previously dating to 70,000 years ago.
...
"This evidence shows that Africa, and particularly southern Africa, was precocious in the development of modern human biology and behavior. We believe that on the far southern shore of Africa there was a small population of modern humans who struggled through this glacial period using shellfish and advanced technologies, and symbolism was important to their social relations. It is possible that this population could be the progenitor population for all modern humans," Marean says.

The paper, "Early human use of marine resources and pigment in South Africa during the Middle Pleistocene," will be on Nature's website tomorrow.

Tags
Categories

More like this

I wonder what Hawks and Cochran think of the implications of this for their adaptive introgression theory.

First, this suggests that there was not much of a lag, if any, between anatomically modern Homo sapiens and modern human behavior, eliminating the need to posit a much more recent "human revolution." Second, the appearance of these traits in Southern Africa suggest that interbreeding with anatomical archaics in Asia and Europe was not necessary for the appearance of these behaviors.

I would further suggest that the evidence for the differential manifestation of symbolic behaviors (formerly exclusively associated with the 'Upper Paleolithic revolution') in various archaic and anatomically modern human populations is not indicative of the population-level absence or presence of genetic potential. (For example, the 'anatomically modern but cognitively archaic' hypothesis.) I think it likely that both moderns and archaics (including neadertals) had this potential, which was differentially realized depending on socioecological, mimetic, and traditive factors.

Hawks, J and GC Cochran. Dynamics of Adaptive Introgression from Archaic to Modern Humans. PaleoAnthropology. 2006. 101-115.

"We suggest that adaptive introgression of alleles from archaic humans may be one of the central mechanisms leading to the "human revolution." The behavioral characteristics
of modern humans, including the employment of symbolic culture and sophisticated technologies, followed the attainment of modern human anatomical features by a considerable delay ... (T)he long coevolution of modern anatomy and behavior in contact with archaic humans, even as those archaic populations appeared to diminish, provided a rich source of adaptations for the expanding modern population."

Modern human behaviour = eating shellfish?

Must... avoid obvious... jokes... religious... dietary restrictions... Noooo!

coluga, i think we're going to quibble over quantitative details. in any case, the sweep of africans out of that continent circa 50,000 K bp does imply that these populations were different, superior, in some way vis-a-vis the various archaic h. sapiens populations.

Razib: "the sweep of africans out of that continent circa 50,000 K bp does imply that these populations were different, superior, in some way vis-a-vis the various archaic h. sapiens populations"

Certainly. But this advantage could be due to a) genes involved in immunity, digestion, and metabolism rather than cognitive ability and/or b) cultural differences related to technology, social organization, warfare tactics, or foraging behavior.

There are multiple models of when and where modern symbolic cognitive abilities first arose. 1) Sapiens grade homo around 400K bp (thus all later archaics and amhs), 2) origin of anatomically modern Homo sapiens around 170K bp, 3) just prior to amhs expansion out of Africa across globe (and thus shared by all amhs) around 50K bp , 4) Upper Paleolithic revolution in Eurasia about 35K bp, then spreading to other populations.

Marean's finding supports only 1) and 2).

In "The Coming of the Age of Iron" the use of pigments is a precursor of metal production, since many pigments are ores (e.g., ochre is an iron ore). A highly recommended book, even though uneven and badly edited.

In the very earliest periods, art and ornamentation have begun to develop while the technology is still Stone Age (though stone age technology isn't easy to produce at all -- arrowheads,bowstrings, bows and arrows are not really easy to make from scratch without tools even if you already have the concept in mind.)

By John Emerson (not verified) on 17 Oct 2007 #permalink

a) genes involved in immunity, digestion, and metabolism rather than cognitive ability and/or b) cultural differences related to technology, social organization, warfare tactics, or foraging behavior.

i doubt that it has to do with immunity, digestion or metabolism. especially the first two, at least in a direct manner. after all, what's the likelihood that an african population would be better adapted for eurasian pathogens and food stuffs? so i think it has to be cognitive/culture, either or both. a cultural toolkit could reshape the environment as one moves north and east so that they are better adapted than the locals.

on the issues of genetic adaptations re: immunity. one could model a scenario where much higher population densities due to in sit cultural evolution/innovation result in a local population which breaks out first with immunity to the density dependent pathogens. these pathogens could sweep through local hominid groups and allow the immunes to out-compete, but over the long run this doesn't seem to give the africans enough of an advantage to nearly totally replace the local genetic substratum. plagues will out run peoples.

i could exposit on this more later...perhaps i'll turn this into a post? any rebuttals welcome.

As I've said before, even though prehistory happened long ago once and for all and never will change, one turn of the spade can rewrite prehistory just like that.

Actually it takes a decade or two, but even though falsificationism is passe, in archaeology and related fields falsification really seems to happen. But there's so little evidence that the new improved theories are fragile too.

By John Emerson (not verified) on 17 Oct 2007 #permalink

But there's so little evidence that the new improved theories are fragile too.

yeah. we'll never get good data from the congo basin for example. the climate isn't the best for extracting fossil remains.

People talk about 'modern human behavior' as if it were a boolean variable rather than a quantitative trait.
Likely they're wrong.

gcochran: "'modern human behavior' as if it were a boolean variable rather than a quantitative trait."

However continuous or discontinuous, major hallmarks are being shifted far earlier and to southern Africa. The difference between the European Upper Paleolithic and African Middle Paleolithic keeps getting narrower.

The difference between the European Upper Paleolithic and African Middle Paleolithic keeps getting narrower.

could you add some quantitative precision here? i'm curious as to the scale and magnitude's of shift that you have in mind. feel free to analogize with other periods & places.

Features once associated mainly or exclusively with Upper Paleolithic:

Pinnacle Point 170K bp

- pigment suggestive of symbolic use
- compound tools
- bladelets
- exploitation of marine resources

Blombos cave 70K bp
http://www.accessexcellence.org/WN/SU/caveart.html
http://www.svf.uib.no/sfu/blombos/Modern_Human_Behaviour_Debate.html

- geometric art
- decorative shells
- worked bone

International Herald Tribune
http://www.iht.com/bin/printfriendly.php?id=7935913

"Until recently, anthropologists generally assumed that modern human behavior arose much more recently, probably around 45,000 years ago, as a consequence of some unidentified change in brain function that favored communication and symbolic thinking to express social status and group identity. That interpretation was based on the apparently sudden appearance of art and self-adornment at sites in Europe."