Archaeologica.org

I have volunteered the genitalia of all posters on this site for investigation.

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A few months ago a paper was published on the genetics of human head lice. It is available free http://darwin.zoology.gla.ac.uk/~vsmith ... index.html
on PLOS.

The Abstract

Parasites can be used as unique markers to investigate host evolutionary history, independent of host data. Here we show that modern human head lice, Pediculus humanus, are composed of two ancient lineages, whose origin predates modern Homo sapiens by an order of magnitude (ca. 1.18 million years). One of the two louse lineages has a worldwide distribution and appears to have undergone a population bottleneck ca. 100,000 years ago along with its modern H. sapiens host. Phylogenetic and population genetic data suggest that the other lineage, found only in the New World, has remained isolated from the worldwide lineage for the last 1.18 million years. The ancient divergence between these two lice is contemporaneous with splits among early species of Homo, and cospeciation analyses suggest that the two louse lineages codiverged with a now-extinct species of Homo and the lineage leading to modern H. sapiens. If these lice indeed codiverged with their hosts ca. 1.18 MYA, then a recent host switch from an archaic species of Homo to modern H. sapiens is required to explain the occurrence of both lineages on modern H. sapiens. Such a host switch would require direct physical contact between modern and archaic forms of Homo.
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So this raises an interesting question - Why is the species of louse that has been isolated from the worldwide lineage for 1.18 million years only found in the Americas?

Now there are many possible solutions that would involve some rather unlikely sequences of events. A straight forward answer would be that some early variety of Homo carried this ancient lineage to the Americas where it was isolated from the rest of the world and later Homo sapiens entering the Americas became the new host.

Are you nit-picking?

He told me that everything is proceeding slower than intended due to a lack of subjects. As a result, I have volunteered the genitalia of all posters on this site for investigation. I'm sure he'll find plenty of research material here.

By the way, you should post this over at Ma'at, Cog, just to yank their chains a bit.

(b) Alternate view: An ancient hominid was isolated in the Americas for over a million years and then went extinct after H. sapiens arrived.

Now there are many possible solutions that would involve some rather unlikely sequences of events. A straight forward answer would be that some early variety of Homo carried this ancient lineage to the Americas where it was isolated from the rest of the world and later Homo sapiens entering the Americas became the new host.

He scratched himself into extinction

Parasites can be used as unique markers to investigate host evolutionary history, independent of host data. Here we show that modern human head lice, Pediculus humanus, are composed of two ancient lineages, whose origin predates modern Homo sapiens by an order of magnitude (ca. 1.18 million years). One of the two louse lineages has a worldwide distribution and appears to have undergone a population bottleneck ca. 100,000 years ago along with its modern H. sapiens host. Phylogenetic and population genetic data suggest that the other lineage, found only in the New World, has remained isolated from the worldwide lineage for the last 1.18 million years. The ancient divergence between these two lice is contemporaneous with splits among early species of Homo, and cospeciation analyses suggest that the two louse lineages codiverged with a now extinct species of Homo and the lineage leading to modern H. sapiens. If these lice indeed codiverged with their hosts ca. 1.18 million years ago, then a recent host switch from an archaic species of Homo to modern H. sapiens is required to explain the occurrence of both lineages on modern H. sapiens. Such a host switch would require direct physical contact between modern and archaic forms of Homo.

This is the abstract of a much longer paper. Wolpoff is a multi-regionalist.
Naturally, the simpler solution of humans in the Americas in very ancient times is not discussed.

Thanks for the article, Beags. Interestingly enough, Wolpoff's multiregionalist theory only holds up if the ancient hominids were isolated in Australia or the Americas. Charlie, maybe I'll invite him to the party.