Secret_History

228 The Secret History of the World
Actually, the disappearance of a whole, distinct group of human type beings at
such a relatively recent point in history, is scary as all get-out. Just think about it:
Neanderthals were everywhere in the icy lands of Europe and Western Asia for
over 150,000 years. They were enormously strong and manifestly intelligent. What
went wrong?
It is also proposed that, at the same moment in time that Neanderthal man just
went “poof!” homo sapiens sapiens (that’s us), just dropped in for dinner, so to
speak. Is there a connection between what went wrong for Neanderthal and what
was “right” for modern man? That question is driving a lot of paleontologists
batty.
Allan Wilson and Vincent Sarich of Berkeley undertook to determine the date of
human origins via DNA analysis. They were looking at proteins because they
knew that proteins evolve by accumulating mutations. They also knew that the
proteins in related species are slightly different from one another because of the
mutations that occur after a species splits off from the “common ancestor”.
Differences in proteins can be quantified.
Well, this wasn’t so controversial a thing to be doing until Wilson and Sarich
suggested that mutations occur across the millennia at a steady rate, like the ticks
of a molecular clock. If this was true, it meant that the difference in a given protein
in any two species would indicate not only how related they were, but also how
much time had elapsed since they shared a common ancestor. In other words,
Wilson and Sarich were going to analyze some proteins and tell us when we last
were apes. Everyone was holding their breath for the answer to this one.
Wilson and Sarich’s protein analysis suggested that the common ancestor of
apes and humans had lived only five million years ago. Stretching it to
accommodate errors, they could only give it eight million years. “To put it as
bluntly as possible,”, Sarich wrote, “one no longer has the option of considering a
fossil specimen older than about eight million years as a hominid no matter what
it looks like”.
The idea that there was or was not any genetic connection between Cro-Magnon
and Neanderthal led to many hot debates. A team of U.S. and German researchers
extracted mitochondrial DNA from Neanderthal bone showing that the
Neanderthal DNA sequence falls outside the normal variation of modern humans.
The researchers compared the Neanderthal sequence with 2,051 human
sequences and 59 common chimpanzee sequences. They found that the differences
in Neanderthal DNA occurred at sites where differences usually occur in both
humans and chimps. In other words, Neanderthal was simply a different species.
When the researchers looked at the Neanderthal sequence with respect to 994
human mitochondrial DNA lineages including Africans, Europeans, Asians,
Native Americans, Australians and Pacific Islanders, they found the number of
base pair differences between the Neanderthal sequence and these groups was 27
or 28 for all groups.
There is a long and interesting case of some Neanderthal remains in a cave in
Israel that some scientists were attempting to utilize as evidence that this was the
region in which Neanderthal morphed into anatomically modern man. The
interested reader may want to have a look at The Neanderthal Enigma by James
Shreeve for a blow-by-blow account of this idea and how it was shot down. The