Researchers from the University of Washington, Seattle, arrived at this conclusion by comparing the whole genome sequences of modern humans
against our Denisovan ancestors.
Previously, the oldest fossils of modern humans
found outside of Africa were somewhere from 90,000 to 120,000 years old, also in Israel.
The analysis was carried out by a machine-learning algorithm that could differentiate between components of both kinds of ancestral DNA, which are more similar to one another than to modern humans
Based on this new data, modern humans
probably interbred with Neandertals between about 50,000 and 60,000 years ago, the team estimates, rather than over a longer period extending further back in the Stone Age (SN: 11/3/12, p.
Many researchers argue the interbreeding scenario is more likely, because it fits the genetic patterns seen in studies that compared genomes from many modern humans
Golovanova and his colleagues believe that the Neandertals were long gone from the cave before modern humans
showed up, but not all scientists agree.
Use of cereals was previously not thought to have developed until some 90,000 years later, when modern human
behaviour began to emerge.
We show that early modern humans
72,000 years ago, and perhaps as early as 164,000 years ago in coastal South Africa, were using carefully controlled hearths in a complex process to heat stone and change its properties, a process known as heat treatment," said lead author Kyle Brown.
EARLY modern humans
may have migrated out of Africa 20,000 years later than was previously thought.
Until such time as fossils of anatomically modern humans
dating to before 200,000 years are found in Asia or Europe this remains the most plausible hypothesis.
There is added evidence that chance, rather than natural selection, best explains why the skulls of modern humans
and ancient Neanderthals evolved differently.
evolved in the east of the continent spreading out across the globe about 54,000 years ago.