Humans in Asia survived Toba super-eruption 74,000 years ago

Chris Clarkson and company have produced a study arguing that the super volcano Toba eruption of 74,000 years ago did not lead to a population bottleneck in Asia, as has been suggested.  Brook Hays of UPI writes:

For the study, scientists analyzed evidence of human populations and climate change across a significant stratigraphic record -- a column of rock and sediment layers comprising 80,000 years of history -- from the Dhaba dig site in northern India's Middle Son Valley.

The column yielded stone artifacts suggesting Middle Palaeolithic tool-using populations were present in India prior to the Toba eruption.

"Although Toba ash was first identified in the Son Valley back in the 1980s, until now we did not have associated archaeological evidence, so the Dhaba site fills in a major chronological gap," researcher J.N. Pal, professor of ancient history and archaeology at the University of Allahabad in India, said in a news release.

The authors argue that there are stone tools at the Dhaba site the strongly resemble Middle Stone Age tools in Northeast Africa. The occupation levels go down to 48,000 years ago, where Levallois and microlithic tools are found. This suggests continuous occupation of the site by different groups with similar stone tool technologies.

Time to chuck another theory into the dustbin of history.  

'Swiss Army knife of prehistoric tools' Found in China

Science Daily is on a roll.  This came out a bit back during the late semester crunch and I didn't get a chance to post about it.  Stone tools have been found in south China that appear to be made using the Levallois technology, which originated during the Middle Stone Age, in Africa.  They write:

A study by an international team of researchers, including from the University of Washington, determines that carved stone tools, also known as Levallois cores, were used in Asia 80,000 to 170,000 years ago. Developed in Africa and Western Europe as far back as 300,000 years ago, the cores are a sign of more-advanced toolmaking -- the "multi-tool" of the prehistoric world -- but, until now, were not believed to have emerged in East Asia until 30,000 to 40,000 years ago.

And now the, somewhat, startling conclusion:

With the find -- and absent human fossils linking the tools to migrating populations -- researchers believe people in Asia developed the technology independently, evidence of similar sets of skills evolving throughout different parts of the ancient world.

This particular conclusion seems somewhat ignorant of the fossil record, which clearly has hominins in the area that have distinct Neandertal traits.  The authors, in fact, even mention the possibility that the appearance of the tools might be tied to these earlier migrations, then seem to dismiss this for reasons that are, in my mind, not clear. 

The site, itself, Guanyindong Cave in Guizhou Province, is not new, having been excavated in the 1960s and 1970s.What is new is the date of 80-170 kya.  Levallois tools were thought to have arrived in the area around 30-40 kya and are seen as the artifacts of a late migration.  This re-dating of the sediments of Guanyindong Cave means that these kinds of tools were in the area some 100 ky earlier than was originally thought.  I do, however, think their evidence for independent origin is sparse.