July 31, 2013

Origin of the Iberomaurusian

This seems to be in wonderful agreement with the coalescence ages of haplogroups M1 and U6. I would say that some type of Into-Africa migration makes the best sense of the totality of the evidence, now that we know that the Iberomaurusian appears after a hiatus in occupation.

Journal of Human Evolution doi:10.1016/j.jhevol.2013.06.003

Origins of the Iberomaurusian in NW Africa: New AMS radiocarbon dating of the Middle and Later Stone Age deposits at Taforalt Cave, Morocco

R.N.E. Barton et al. Recent genetic studies based on the distribution of mtDNA of haplogroup U6 have led to subtly different theories regarding the arrival of modern human populations in North Africa. One proposes that groups of the proto-U6 lineage spread from the Near East to North Africa around 40–45 ka (thousands of years ago), followed by some degree of regional continuity. Another envisages a westward human migration from the Near East, followed by further demographic expansion at ∼22 ka centred on the Maghreb and associated with a microlithic bladelet culture known as the Iberomaurusian. In evaluating these theories, we report on the results of new work on the Middle (MSA) and Later Stone (LSA) Age deposits at Taforalt Cave in Morocco. We present 54 AMS radiocarbon dates on bone and charcoals from a sequence of late MSA and LSA occupation levels of the cave. Using Bayesian modelling we show that an MSA non-Levallois flake industry was present until ∼24.5 ka Cal BP (calibrated years before present), followed by a gap in occupation and the subsequent appearance of an LSA Iberomaurusian industry from at least 21,160 Cal BP. The new dating offers fresh light on theories of continuity versus replacement of populations as presented by the genetic evidence. We examine the implications of these data for interpreting the first appearance of the LSA in the Maghreb and providing comparisons with other dated early blade and bladelet industries in North Africa.



Anonymous said...

Absence of evidence is not proof of absence. The flakes are missing for 3k in one cave. It is quite a stetch to make assumptions about a discontinuity across the whole of north africa.

Anonymous said...

Now I come to think of it, the 3k gap in the flake record corresponds to the last Glacial Maximum. A darned good reason for some kind of sociogeographic disruption. Perhaps the cave leaked or something. Perhaps it was just too chilly.

eurologist said...

The connection with Heinrich Event 2 (cold and dry in N Africa) and LGM (wet phase, locally) seems pretty straightforward, as also argued by the authors.

How wide was the Strait of Gibraltar during LGM? The nice thing is that the timing for a crossing would have been perfect.

Joe Lyon said...

Iberomaurusian is now back to 21,000 years ago...the ibero-maurusians were described as even more neanderthaloid than classic cromagnons...and there were neasnderthals on the rock of Gibralter 21,000 years ago.
Why cant the ibero-maurusians be neanderthal hybrids from iberia escaping europe to mate with afro-asiatics migrating into morocco slightly earlier..