[asa] Archaic inbreeding

From: Glenn Morton <glennmorton@entouch.net>
Date: Sun Mar 11 2007 - 12:54:23 EDT

One of the things I have longed argued for, and occasionally received flack
on this list for, is the belief that humans and the archaic hominids,
Neanderthal and H. erectus are one evolving species,meaning that if we have
the image of God, then so did they. I have cited their actions--buiding
altars (http://home.entouch.net/dmd/religion.htm), the manufacture of art
(Leakey's 1.6 million year old phonolite pebble; 400 kyr painted Tan-tan
figurine, and the 325 kyr old Berekhat Ram figurine), and their ability to
plan ahead (http://www.asa3.org/asa/PSCF/1999/PSCF9-99Morton2.html) as
evidence of this humanity.

But, the Out of Africa view had predominated over the years and it was hard
to get interbreeding taken seriously, even with the discovery of modern
humans with Neanderthal traits, like the 24 kyr old Lagar Velho child of
Portugal, or even the Oase skulls from Romania. But now, the idea of
interbreeding may be coming into the mainstream (as it should have long ago
given that the evidence for human genes with ages of 200 kyr to 5.5 million
years http://home.entouch.net/dmd/hegene.htm)

This month New Scientist has an article "The Neanderthal Within." It talks
about some of this evidence for interbreeding with the Neanderthals.

"Like many genes involved with brain development, microcephalin has evolved
rapidly in humans. In previous studies, Lahnshowed that one variant of
microcephalin appeared about 40,000 years ago and has since swept through
the population, propelled by the power of natural selection. The new variant
is found in 70 per cent of living people. "We don't yet know exactly what
this variant does or why it is being selected for - it could be something to
do with cognition," says Lahn."
"The obvious interpretation is that the new version arose 40,000 years ago
via a chance mutation in the microcephalin gene. Lahn thinks otherwise. In a
paper published last year, he looked at a haplotype within microcephalin. On
the basis of sequence differences between the old and new versions of the
gene, he concluded that the two are so different that they must have
diverged at least 1 million years ago (Proceedings of the National Academy
of Sciences, vol 103, p 18178)."
"This combination of deep ancestry on one level and shallow ancestry on
another suggests that something very unusual might have happened. It is as
if the new version of microcephalin split off from our evolutionary lineage
a million years ago, then jumped back in 40,000 years ago. According to
Lahn, that is exactly what happened. By far the most likely explanation, he
says, is that the newer version of the gene evolved in a separate species of
human - probably Neanderthals - and then entered our lineage through
interbreeding." Dan Jones, "The Neanderthal Within," New Scientist, March 3,
2007, p. 31

The article also talks about a study of the PDHA1 gene, which shows a
pattern which is incompatible with humanity being a single small group of
people 100-200kyr ago. The article says:

"They found that the sequences could be clumped into two basic types, or
lineages, which last shared a common ancestor a whopping 1.8 million years
ago. Then 200,000years ago one of the lineages split again (Proceedings of
the National Academy of Sciences, volg6, p 3320). But if humans evolved from
a small, reproductively isolated group about 160,000 years ago, how could
the PDHA1 haplotype have diverged 1.8 million years ago, and again 200,000
years ago? "The pattern is completely incompatible with a model in which
modem humans derive from a single population," says Garrigan." Dan Jones,
"The Neanderthal Within," New Scientist, March 3, 2007, p. 31

This means that if we really want Adam to be the progenitor of all humans, a
theological position most take, then Adam must be at least 1.8 million years
old given this data (but given data on my hegene webpage, the age must be
older than this).

This post can easily be dismissed by one and all because in it I am caught

They're Here: The Pathway Papers
Foundation, Fall, and Flood
Adam, Apes and Anthropology


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Received on Sun Mar 11 11:55:06 2007

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