Recent Genetic Research Shows Chimps More Distant From Humans, Neanderthals Closer [Excerpts]
Research published in Nature over the past few months is showing a much greater genetic distance between humans and chimps than previously thought, while revealing a closer one between humans and Neanderthals.
A Nature paper from January, 2010 titled, "Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content," found that Y chromosomes in humans and chimps “differ radically in sequence structure and gene content,” showing “extraordinary divergence” where “wholesale renovation is the paramount theme.” Of course, the paper attributes these dramatic genetic changes to “rapid evolution during the past 6 million years.”
More than 30% of the chimp Y chromosome lacks an alignable counterpart on the human Y chromosome, and vice versa, whereas this is true for less than 2% of the remainder of the genome.“
But not wishing to offend the "myth of 1%", the Nature news article carefully adds, “The remainder of the chimp and human genomes are thought to differ in gene number by less than 1%.”
While this research takes us genetically further from apes, a more recent report in Nature news takes us genetically much closer to Neanderthals. Titled, “Neanderthals may have interbred with humans,” the article explains that “A genetic analysis of nearly 2,000 people from around the world indicates that such extinct species interbred with the ancestors of modern humans twice, leaving their genes within the DNA of people today.” According to this new article:
[I]t may help explain the fate of the Neanderthals, who vanished from the fossil record about 30,000 years ago. "It means Neanderthals didn't completely disappear," says Jeffrey Long, a genetic anthropologist at the University of New Mexico, whose group conducted the analysis. There is a little bit of Neanderthal leftover in almost all humans, he says.
Textbooks often depict Neanderthals as primitive, bungling brutes with a vaguely human-like form (see above)—an attempt to instill the ape-to-human icon in students. But as Time Magazine reported in 1999, there’s increasing evidence showing that this evolutionary interpretation was wrong, and Neanderthals were essentially “all just people”:
The real message, [a Washington University paleoanthropologist Erik] Trinkaus believes, is that to people living in the Stone Age, Neanderthals were just another tribe. "They may have had heavier brows or broader noses or stockier builds, but behaviorally, socially and reproductively they were all just people."
(Michael D. Lemonick, " A Bit of Neanderthal in Us All?, " Time Magazine (April 25, 1999).)
http://www.evolutionnews.org/2010/04/recent_genetic_research_shows.html
