Demise of the Neanderthals: Another Theory

BBC News has an interesting article up about Neanderthals. The article title is misleading because it seems to saying that a cold snap was responsible for killing off the Neanderthals.

The rest of the article is quite good though. It concerns research at Gorham’s Cave on Gibraltar. Current thinking is that the Neanderthals retreated into refuges on the Iberian Peninsula as anatomically modern Homo sapiens advanced further and further into Europe. Research at Gorham’s Cave originally focused on pollen analysis – the researchers were trying to understand how the climate had changed in the area over the last 15,000 years – but:

During the course of this work, they also obtained ages for sediment samples from the cave, using radiocarbon dating and uranium-thorium dating.
Sediment layers containing stone tools of a style known to have been made by Neanderthals were found to date from 45,000 years ago until 21,000 years ago.

As the BBC article points out the radiocarbon dates are uncalibrated so caution is needed in interpreting them. Some Neanderthal bones have been discovered at the site, including a male skull fragment, but there are problems correlating the bones with the dates:

“The human bones have been recovered in different excavation campaigns over 50 years. The relationship between them and the dates I provide must be treated with caution,” Professor Carrion told BBC News.
He added that sediments in parts of the cave could have been churned up, mixing old bones in with younger material. He suggested Carihuela should be re-excavated to resolve some of the controversies surrounding the site.

Unfortunately, there is a political dispute over digging rights between the national and regional governments so at this point the site is closed.
The climate research indicated a sharp downturn in temperature:

Sediment cores drilled from the sea bed near the Balearic Islands show the average sea-surface temperature plunged to 8C (46F). Modern-day sea surface temperatures in the same region vary from 14C (57F) to 20C (68F).

But it wasn’t the cold, it was the results of the cold that got the Neanderthals. Apparently the lower temperature locked up more water and caused a drought (there is evidence for a decrease in the amount of water rivers in the area were emptying into the sea). The drought in turn killed off the animals being hunted by the Neanderthals.
The research is being published in Quaternary Science Reviews. An abstract is available here. If anybody out there has access can you shoot a copy my way?
Update: I have a copy of the paper now (two copies actually) thanks! I just finished reading it and it is quite intersting.

4 Responses

  1. Sent.

  2. If the cold snap finished off the Neanderthals, how come it didn’t also finish off the Cro Magnons?

  3. First off, I am not 100% in love with your tone…

  4. If you still need a copy of the full article, I have a pdf of it on my hard drive. I will be more than happy to share. Just e-mail me offlist if you would like a copy and I will send you one.
    Anne G

Comments are closed.

%d bloggers like this: