A genetic analysis of head and body lice suggests that people may have begun making and wearing clothing as early as 190,000 years ago. Credit: Janice Harney Carr, Center for Disease Control
Posted on 04/23/2010 6:41:29 AM PDT by SunkenCiv
Using DNA to trace the evolutionary split between head and body lice, researchers conclude that body lice first came on the scene approximately 190,000 years ago. And that shift, the scientists propose, followed soon after people first began wearing clothing... sheds light on a poorly understood cultural development that allowed people to settle in northern, cold regions, said Andrew Kitchen of Pennsylvania State University in University Park. Armed with little direct evidence, scientists had previously estimated that clothing originated anywhere from around 1 million to 40,000 years ago. An earlier analysis of mitochondrial DNA from the two modern types of lice indicated that body lice evolved from head lice only about 70,000 years ago... Though well suited to gauging the timing of evolutionary events, mitochondrial DNA is a relatively small part of the genome. Kitchen's team examined both mitochondrial and nuclear DNA samples from head and body lice, yielding the much older, and presumably more accurate, estimate of when body lice first evolved... The researchers calculated relatively fast mutation rates for both forms of lice, so the new age estimate for the divergence of body lice from head lice is a conservative one. It’s possible for body lice to have evolved from head lice in only a few generations, according to laboratory studies, Kitchen said. No evidence indicates that head lice can evolve from body lice.
(Excerpt) Read more at sciencenews.org ...
A genetic analysis of head and body lice suggests that people may have begun making and wearing clothing as early as 190,000 years ago. Credit: Janice Harney Carr, Center for Disease Control
The Neandertal EnigmaFrayer's own reading of the record reveals a number of overlooked traits that clearly and specifically link the Neandertals to the Cro-Magnons. One such trait is the shape of the opening of the nerve canal in the lower jaw, a spot where dentists often give a pain-blocking injection. In many Neandertal, the upper portion of the opening is covered by a broad bony ridge, a curious feature also carried by a significant number of Cro-Magnons. But none of the alleged 'ancestors of us all' fossils from Africa have it, and it is extremely rare in modern people outside Europe." [pp 126-127]
by James Shreeve
in local libraries
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“since both species had already lost most body hair “
???? How do they know?
You’re onto something there — to get a corroborating date, someone should look for really old bottles of anti-lice stuff.
Mmmmmm...
“Momma, don’t clean no fish, cause Daddy’s gonna bring home the crabs.”
My understanding is that DNA is perishable, and that it can’t last that long.
New age estimates compared to the earlier estimates, they are all just a guess and should not be taken as anything else.
The study was done with “mitochondrial DNA from the two modern types of lice”, i.e., living lice. DNA is made up of a number of complex molecules, and of biological origin, so it will break down, or get eaten by something microscopic. Some DNA fragments have been found that go quite far back, but even in purposely preserved remains (such as Egyptian mummies) it’s hit or miss whether analyzable quantities survive. Often the samples that are best come from tooth pulp. The Heidelbergensis sample analyzed in the 1990s was mtDNA, and consisted of fewer than 400 base pairs out of a presumed original number of over 16,000. Those remains were much older than Egyptian mummies, much older than Oetzi.
They are educated guesses, and shouldn’t be derided as anything else.
I shell wish I’d thought of that.
“nude gardening” — so that’s what the kids are calling it now...
You project a lot. There was no derision, only a statement of fact.
I don’t project at all, I only stated a fact.
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