Anthropology.net

A team of paleoanthropologists report in PLoS One analyzed the skulls of several dozen 11,000 year old Paleoamericans and compared them to the skulls of more than 300 1,000 year old Amerindians. They concluded that based on the morphology, there were two distinct waves of colonizers from Asia.

11,000 Year Old Lagoa Santa Brazil Paleoamerican Skull

While we know from a couple genetic studies there are at least two, if not 3 or more waves of colonizers, the morphological evidence is now beginning to make a lot more sense along with the genetic evidence. There’s some concern why the authors didn’t have more North American and Asian samples for comparison, but that’s almost always a critique in any anatomical study.

Two comments in the Science Now news article are particularly entertaining regarding this topic:

“Very interesting–don’t tell some of the tribes in california–they won’t be able to handle real information like this.”

“Exactly. It sounds like the Amerindians stole the land from the Paleoindians? I guess they should pay restitution, right?”

Hubbe, M., Neves, W., & Harvati, K. (2010). Testing Evolutionary and Dispersion Scenarios for the Settlement of the New World PLoS ONE, 5 (6) DOI: 10.1371/journal.pone.0011105

Some heavy hitting names are behind an upcoming paper on Neandertal mobility, which is based upon an isotope analysis of a tooth. A couple of them that you may recognize are Katerina Harvati and Jean-Jacques Hublin. The AP press is saying this research is the first direct evidence the links a Neandertal and his or her range. The press is also quoting Harvarti saying Neandertal mobility is, “highly controversial.”

I appreciate this sort of creative research, but, like Clive Finlayson, I’m a bit confused about what is exactly controversial about considering Neandertals as highly mobile. They were large brained bipedal humans with an adequate arsenal of intelligence to create effective lithic technology. So why wouldn’t they be as mobile as modern day nomadic hunter gatherers? Clive even offered up a snarky remark that John Hawks caught,

“I would have been surprised if Neanderthals didn’t move at least 20 kilometers (12.5 miles) in their lifetime, or even in a year … We’re talking about humans, not trees.”

The specifics behind paper, “Strontium isotope evidence of Neanderthal mobility at the site of Lakonis, Greece using laser-ablation PIMMS,” is that the team sampled the enamel off of 40,000-year-old tooth, found in Greece’s southern Peloponnese region in 2002, for isotopes of strontium. Different regions and ecosystems have specific strontium isotopes in trapped sediment. The isotope is often taken up through the food chain and deposited into the tissues of the plants and animals that inhabit the area. Ultimately, as organisms are consumed, the strontium is absorbed into bodies.

Therefore, screening for the different levels of the isotope from a bone, and comparing that to levels of the isotope found elsewhere, can tell us where a person lived. One of my friends at UCSC began to apply this method in a forensic context, to help identify where in the world a person came from based upon unidentifiable remains.

In the current study, the authors compared ratios of two strontium isotopes (strontium-87 to strontium-86) to where the fossil was found and it didn’t match. They say that means the Neandertal’s diet was based upon some other region of world, and that this Neandertal had a radius of at least 20 kilometers.

Aside from the n=1 critique, I have one major concern that hasn’t yet been voiced. We know the site where a bone is fossilized is often not the exact site of death. And, we’re talking about 1 tooth, a small one too, from a 7-9 year old Neadertal. It is very possibly, even probable, that some natural cause, such as a river or carnivore transported the bone from the site of death to a much different location. If that’s the case, then that would mess up our understanding of mobility — since it wasn’t the actual seven year old who got up and walked 20 kilometers from his or her home base.

What I’m getting at is the tooth did the traveling.

Like I indicated before, we shouldn’t be surprised that Neandertals were capable of being mobile. There shouldn’t even be any controversy. I just don’t think this is isotope comparison the most perfect example that establishes Neanderal mobility… there coulda been a whole slew of natural effects that displaced the bone during 40,000 years and would affect the conclusions drawn by this team.

RICHARDS, M., HARVATI, K., GRIMES, V., SMITH, C., SMITH, T., HUBLIN, J., KARKANAS, P., PANAGOPOULOU, E. (2007). Strontium isotope evidence of Neanderthal mobility at the site of Lakonis, Greece using laser-ablation PIMMS. Journal of Archaeological Science DOI: 10.1016/j.jas.2007.08.018