January 27, 2011

Early expansion of humans into Arabia

From the press release:
The team of researchers, including lead author Simon Armitage from Royal Holloway, University of London, discovered an ancient human toolkit at the Jebel Faya archaeological site in the United Arab Emirates. It resembles technology used by early humans in east Africa but not the craftsmanship that emerged from the Middle East, they say. This toolkit includes relatively primitive hand-axes along with a variety of scrapers and perforators, and its contents imply that technological innovation was not necessary for early humans to migrate onto the Arabian Peninsula. Armitage calculated the age of the stone tools using a technique known as luminescence dating and determined that the artifacts were about 100,000 to 125,000 years old.
Together with the North Africa evidence, Skhul/Qafzeh, and possibly Zhirendong, the new paper suggests that by 100ky ago, modern humans were already a fairly widely distributed species.

See also: Persian Gulf Oasis hypothesis.

Science Vol. 331 no. 6016 pp. 453-456 DOI: 10.1126/science.1199113

The Southern Route “Out of Africa”: Evidence for an Early Expansion of Modern Humans into Arabia

Simon J. Armitage et al.


The timing of the dispersal of anatomically modern humans (AMH) out of Africa is a fundamental question in human evolutionary studies. Existing data suggest a rapid coastal exodus via the Indian Ocean rim around 60,000 years ago. We present evidence from Jebel Faya, United Arab Emirates, demonstrating human presence in eastern Arabia during the last interglacial. The tool kit found at Jebel Faya has affinities to the late Middle Stone Age in northeast Africa, indicating that technological innovation was not necessary to facilitate migration into Arabia. Instead, we propose that low eustatic sea level and increased rainfall during the transition between marine isotope stages 6 and 5 allowed humans to populate Arabia. This evidence implies that AMH may have been present in South Asia before the Toba eruption (1).



lkdjf said...
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eurologist said...

It's not that easy, or rather impossible, when climate doesn't cooperate. Have you tried crossing the Sahara, today, while hunting with spears for (the nonexistent) food or digging for (nonexistent) tubers, trying to drink (nonexistent) water?

There where huge barriers during the cold (and simultaneously dry) phases, and huge water barriers during most of the brief warm intervals. Only at the beginning of warmer, wetter times were conditions right for migration out of Africa - namely, existence of grasslands with grazing animals and fresh water sources, as well as still-low sea levels.

Many, myself included, have argued for years that therefore, an initial migration ooA around 125,000 years ago was most likely for theoretical reasons. Genetics has really poor time estimates, and archeology is just now catching up. Of course, most importantly, at one point we need to associate these tools with AMHs.

DocG said...

As I see it, the best evidence for an early migration is circumstantial, based on the estimated date for the eruption of Mt. Toba, ca 74000 ya. The Toba event has such strong explanatory power that we may not be able to do without it. As with God, if it didn't exist, we might have to invent it.

On an off-topic note, I'd like to take this opportunity to announce the creation of a new blog that might be of interest to many of those reading here. It's called English Proper and is designed as a resource for non-native English speakers who want to improve their writing skills. http://englishproper.blogspot.com/

Readers are invited to submit brief excerpts from any of their writings that might need correcting.

Anonymous said...

I don't understand. A bunch of rocks means an early human migration out of Africa! How about finding some ancient bones in the desiccating climate of Arabia?

It seems believable that humans left NE Africa and entered Asia through the southern corridor and hunted/gathered their way through the monsoon watered shores of the extended shorelines of Arabia and ended up in South Asia which appears to be a genetic cradle of humanity post OOA. However, I doubt Arabia was more than a sojourn to South Asia. Anyway, I would like to see concrete evidence rather than a bunch of rocks which are credited as being tools made by humans.

terryt said...

"But also there is really no evidence that these tools were made by modern man".

My first thought too.

"It resembles technology used by early humans in east Africa but not the craftsmanship that emerged from the Middle East, they say".

Doesn't resemble the contemporary technology of the Middle east, or doesn't resemble the technolgy that later emerged in the Middle east? The description sounds very much like earlier Middle East technologies.

PS said...

i believe its very, very easy for a man to walk across an entire continent in a few months

Sure, but the question is, why would he do that? People seem to have a mental image of human migration as simply setting out in one direction and walking until you run out of land. People needed a reason to migrate. If they were fine where they were, they stayed put until the food ran out.

terryt said...

"People needed a reason to migrate. If they were fine where they were, they stayed put until the food ran out".

Seems to be exactly what they did as they moved through the Pacific Islands. But ... the food ran out on each island fairly rapidly because of rapid population increase. As a result the migration was rapid, as I presume it would have been once humans emerged from Africa and entered ideal habitat, and had learnt how to contend with predators. So early population expansion could also have been rapid but would need to have been confined to ideal habitat. My guess is that ideal habitat was semi-open grassland with trees scattered through it. Dense tropical forest was occupied only once population pressure forced people into it.

Unknown said...

Guys ! you are allow to give comments in this blog ,so, respect scientist's long work and ethic in the field and do not try to discredit their finding with your personal agendas.
Anyone who do not beleive the scientist has to show us his works and publication and just not commenting