Google+ Followers

jeudi 25 octobre 2012

Neandert(h)als: interesting findings in a Science chat

As many of you know, Neandertals or their ancestors appear in Eurasia beginning about 250,000 years ago, while modern humans don't arrive until somewhere around 50,000 years ago--at least according to current evidence.

Neandertals were first discovered in Gibraltar in the 1800s, but researchers didn't know what they were. They only got clued in when specimens were found in the Neander Valley of Germany. Had things turned out differently, they might have been called Gibraltarians instead; but people there say that is just as well.

Comment From Angus  
Would Neanderthals consider it important to have recognizable human traits? Do we believe that it benefits them as a species?

Harold L. Dibble: 
You know, I sometimes wonder why some people argue so strongly that Neandertals have to be considered to be just like us, as if to say otherwise is some kind of insult to them. Considerting our current condition, and our very uncertain future, I tend to think that pushing our brand of humanity on them could be the bigger insult.

Comment From Beth Skwarecki  
What's the current thinking on the Neandertals' diet? Especially how much they hunted vs. ate plant foods. Was their diet likely different from Homo sapiens of the time?

John Speth: 
Hi Beth, a topic dear to my heart! Here I recognize that my views as they are evolving may be more than three standard deviations from the current mean, but here goes anyway. Generally bones are what preserve, big bones are more visible and seemingly of more interest to a lot of people, and reflect a long bias in our own traditions. So since Darwin, and probably long before we have seen big-game hunting as what we as humans are all about and it is what largely drove our evolution. But a close look at modern hunter-gatherers like the Hadza and San (Bushmen) suggests that men do most of their big-game hunting at the time when other foods, gathered mostly by women, are at their peak (baobab, mopane worms, various seeds, nuts and fruit, etc.). Also men's hunting is notoriously unreliable, they fail most of the time, the spend inordinate amounts of time tracking, etc, not a very reliable and effective way of provisioning on a per capita daily basis. Social/political dimensions such as "costly signaling" are now being looked at very closely by behavioral ecologists (same for chimpanzees) and it looks increasingly like male hunting of big game is largely underwritten by women and serves social/political functions first and foremost and provisioning second. In many hunter-gatherers, men would do better in return rates and reliability by doing what women did. There's another entire issue with the nitrogen values in Neanderthals, but I better leave that one alone here. There's also alot of work going on now showing from microfossils in Neanderthal teeth that they were indeed exploiting plant foods. We don't know how much.

Neandertals and modern humans shared a common ancestor that probably lived in Africa about 500,000 years ago. But Neandertals evolved from hominins that moved in Europe and Asia, while modern humans from those that stayed in Africa--at least according to the thinking of most researchers.

On the other side of the coin, humans are incredibly adaptable to cold, with the development of brown (shivering) fat, as demonstrated by military studies and the cold tolerance of the hunter-gatherers of Tierra del Fuego.

Aucun commentaire: