Friday, September 30, 2016

1000 Posts

This is the 1000th post at Dispatches From Turtle Island, which has maintained its rather quirky mix of about 50% physics (508 posts out of 1000) and about 50% anthropology and genetics for the roughly five years that it has been in existence.

As of the time I am writing this post, there have been 1876 published comments (excluding deleted comments), which is an average of almost two comments per substantive post.

There have been 391,729 page views of this blog since its inception, an average of 392 page views per post, although that average is highly skewed by a few posts that have received very high traffic, such as the all time most visited post on this blog about "Pre-Out of Africa Population Sizes and Densities", which has received 12,707 page views.

This blog gets less traffic than its sister blog, Wash Park Prophet, from which it was split off. But, the quality and sophistication of the readership is quite impressive.

Elk Migrations To North America

I missed this interesting study at the time it was originally released. It uses multiple methods to infer the arrival of elk in North America via Beringia which generally coincides with the human migration to North America via essentially the same route at about the same time.
Human colonization of the New World is generally believed to have entailed migrations from Siberia across the Bering isthmus. However, the limited archaeological record of these migrations means that details of the timing, cause and rate remain cryptic. 
Here, we have used a combination of ancient DNA, 14C dating, hydrogen and oxygen isotopes, and collagen sequencing to explore the colonization history of one of the few other large mammals to have successfully migrated into the Americas at this time: the North American elk (Cervus elaphus canadensis), also known as wapiti. 
We identify a long-term occupation of northeast Siberia, far beyond the species’s current Old World distribution. Migration into North America occurred at the end of the last glaciation, while the northeast Siberian source population became extinct only within the last 500 years. This finding is congruent with a similar proposed delay in human colonization, inferred from modern human mitochondrial DNA, and suggestions that the Bering isthmus was not traversable during parts of the Late Pleistocene. Our data imply a fundamental constraint in crossing Beringia, placing limits on the age and mode of human settlement in the Americas, and further establish the utility of ancient DNA in palaeontological investigations of species histories.
Meirav Meiri, et al., "Faunal record identifies Bering isthmus conditions as constraint to end-Pleistocene migration to the New World", Proceedings of the Royal Society B: Biological Sciences (December 11, 2013) (Hat tip to Linear Population Model).

Thursday, September 29, 2016

What Did Neanderthal Speech Sound Like?

Based upon the physical size and shape of the Neanderthal voice box, nasal cavity, rib cage and thick heavy skull, we can infer that Neanderthal speech was probably loud, and considerably more high pitched and nasal sounding than one might expect, compared to modern human alive today.