Tuesday, January 8, 2019

Earlier Out of Africa Evidence

A jaw bone and teeth found at least 177,000 years ago in what is now Israel appears to be that of a modern human, pushing back the earliest known evidence of modern humans out of Africa by at least 57,000 years. This is much older than the estimated date of the most recent common ancestor (TMRCA) of all extent Eurasians based upon some genetic evidence although other genetic evidence suggests an even earlier date.
Earliest modern humans out of Africa

Recent paleoanthropological studies have suggested that modern humans migrated from Africa as early as the beginning of the Late Pleistocene, 120,000 years ago. Hershkovitz et al.now suggest that early modern humans were already present outside of Africa more than 55,000 years earlier. During excavations of sediments at Mount Carmel, Israel, they found a fossil of a mouth part, a left hemimaxilla, with almost complete dentition.

The sediments contain a series of well-defined hearths and a rich stone-based industry, as well as abundant animal remains. Analysis of the human remains, and dating of the site and the fossil itself, indicate a likely age of at least 177,000 years for the fossil—making it the oldest member of the Homo sapiens clade found outside Africa.

Abstract

To date, the earliest modern human fossils found outside of Africa are dated to around 90,000 to 120,000 years ago at the Levantine sites of Skhul and Qafzeh. A maxilla and associated dentition recently discovered at Misliya Cave, Israel, was dated to 177,000 to 194,000 years ago, suggesting that members of the Homo sapiens clade left Africa earlier than previously thought. This finding changes our view on modern human dispersal and is consistent with recent genetic studies, which have posited the possibility of an earlier dispersal of Homo sapiens around 220,000 years ago. The Misliya maxilla is associated with full-fledged Levallois technology in the Levant, suggesting that the emergence of this technology is linked to the appearance of Homo sapiens in the region, as has been documented in Africa.
Israel Hershkovitz, et al., "The earliest modern humans outside Africa" 359 (6374) Science 456-459 (January 26, 2018) DOI: 10.1126/science.aap8369

4 comments:

neo said...

"A jaw bone and teeth found at least 177,000 years ago in what is now Israel appears to be that of a modern human, pushing back the earliest known evidence of modern humans out of Africa by at least 57,000 years. This is much older than the estimated date of the most recent common ancestor (TMRCA) of all extent Eurasians based upon some genetic evidence although other genetic evidence suggests an even earlier date."

if verified, it sounds like estimated dates based on DNA and genetics is faulty and unreliable. a lot of assumptions are made to make these estimates, and when compared against fossils, seems to be wrong.

Marnie said...

This is an exciting paper. However, the author ordering on this paper looks suspicious. As least, the contributions of each of the authors should be stated explicitly.

andrew said...

"if verified, it sounds like estimated dates based on DNA and genetics is faulty and unreliable. a lot of assumptions are made to make these estimates, and when compared against fossils, seems to be wrong."

Or, it could be that first wave Out of Africans were almost completely replaced by later Out of Africans, or that there was a common community from ca. 177,000 years ago to 50,000 years ago, after which there was an expansion.

@Marnie I've discussed in comments at other blogs the desirability of changing how credit is given in many author papers with both better descriptions of relative contributions and the use of collaborations as entities rather than individuals in "big science".

Marnie said...

Most papers are published in electronic format and are read in electronic format. Therefore, clickable links to author contributions are not that difficult to do anymore. I think there is a lot of political jostling in paleoanthropology for first and last author. Something should be done to improve the situation for very accomplished but less visible people working in the field.