Posted on 12/11/2007 12:34:37 AM PST by anymouse
Human evolution has been moving at breakneck speed in the past several thousand years, far from plodding along as some scientists had thought, researchers said on Monday.
In fact, people today are genetically more different from people living 5,000 years ago than those humans were different from the Neanderthals who vanished 30,000 years ago, according to anthropologist John Hawks of the University of Wisconsin.
The genetic changes have related to numerous different human characteristics, the researchers said.
Many of the recent genetic changes reflect differences in the human diet brought on by agriculture, as well as resistance to epidemic diseases that became mass killers following the growth of human civilizations, the researchers said.
For example, Africans have new genes providing resistance to malaria. In Europeans, there is a gene that makes them better able to digest milk as adults. In Asians, there is a gene that makes ear wax more dry.
The changes have been driven by the colossal growth in the human population -- from a few million to 6.5 billion in the past 10,000 years -- with people moving into new environments to which they needed to adapt, added Henry Harpending, a University of Utah anthropologist.
"The central finding is that human evolution is happening very fast -- faster than any of us thought," Harpending said in a telephone interview.
"Most of the acceleration is in the last 10,000 years, basically corresponding to population growth after agriculture is invented," Hawks said in a telephone interview.
The research appears in the journal Proceedings of the National Academy of Sciences.
FAVORABLE GENE MUTATIONS
The researchers looked for the appearance of favorable gene mutations over the past 80,000 years of human history by analyzing voluminous DNA information on 270 people from different populations worldwide.
Data from this International HapMap Project, short for haplotype mapping, offered essentially a catalogue of genetic differences and similarities in people alive today.
Looking at such data, scientists can ascertain how recently a given genetic change appeared in the genome and then can plot the pace of such change into the distant past.
Beneficial genetic changes have appeared at a rate roughly 100 times higher in the past 5,000 years than at any previous period of human evolution, the researchers determined. They added that about 7 percent of human genes are undergoing rapid, relatively recent evolution.
Even with these changes, however, human DNA remains more than 99 percent identical, the researchers noted.
Harpending said the genetic evidence shows that people worldwide have been getting less similar rather than more similar due to the relatively recent genetic changes.
Genes have evolved relatively quickly in Africa, Asia and Europe but almost all of the changes have been unique to their corner of the world. This is the case, he said, because since humans dispersed from Africa to other parts of the world about 40,000 years ago, there has not been much flow of genes between the regions.
ggg ping
they'll still come to the same conclusion.
How did you infer that?
It is pretty insane of people trying to argue that human evolution has sped up when humans have short circuited natural selection by discovering medicine, caring for those with genetic defects, etc. If what you theorize is happening, evolution, speeds up when your mechanism, natural selection, is short circuited by human action, you need a new theory.
Science failed to formulate macro evolution.
I’ll stick to creation.
Empirical research using the scientific method has yet to demonstrate the unequivocally positive nature of a single mutation:
http://freerepublic.com/focus/f-news/1934898/posts
Just since the invention of the computer, human buttocks have widened by an average of 6.35 inches.
Against a background of gradual evolution, juxtaposing our tiniest-of-Humankind population for differences would be expected to result in a "punctuated-equilibrium" moment.
(I'm SO smart after morning coffee).
:^)
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
“The researchers looked for the appearance of favorable gene mutations over the past 80,000 years of human history by analyzing voluminous DNA information on 270 people from different populations worldwide.”
Leaving aside science/evolution/creationism etc etc...the first thing that strikes me is that those are some pretty sweeping statements to be made on what is a suspiciously small sample.
I’m willing to bet some newsie has blown up preliminary results of what is still very much a work in progress
Oh, I wasn't aware that the "test" had a deadline.
about 7 percent of human genes are undergoing rapid, relatively recent evolution. Even with these changes, however, human DNA remains more than 99 percent identical...and a genetic predisposition to basic math ability turns out to be mythical.
Nope. It's still selective pressure and selection, no matter who or what changes the environment. And we human beings are no less "natural" than any other organism on the planet.
Most of the significant evolutionary pressures concern diseases, both inherited and acquired. Even the dumbest idiot is usually provided some sort of charity/hand-out in most societies. Intelligence needn’t necessarily be a force for evolution as much as the other factors are, in modern human beings. An exception to this would be among small groups of people living nomadic lifestyles, where the size of the group is too small for members to be able to compensate for the shortcomings of other members.
Since medicine has made ANY difference to survival only since 1920, and a great difference only since about 1940, that leaves more than 10,000 years of civilization in which crowding, new diseases, etc., have introduced greater natural selection effects, not less.
That’s amazing. How did Evolution know that somebody would invent dentists?
The Universe is expanding faster than man can keep up, yet we have anthropologists that can travel to Africa and point to the ground and tell God “This is where you created man” right here in this spot!! They love to sell the fairy tell about Africa. How many times have the continents broken up and divided again and again
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