Skip to comments.Culture Shock May Explain Similarity Between Humans
Posted on 01/10/2009 2:19:53 AM PST by neverdem
Although humans come in many shapes and sizes, from the compact Inuit of the Arctic to the willowy Masai warriors of Africa, any two people are a lot more alike genetically than any pair of chimpanzees or gorillas. The reason may be our advanced culture, according to a new study. Our ancestors' different tools, eating habits, and even body decorations limited their mate choices to individuals of a similar culture, the work suggests, reducing the spread of new mutations across many groups. Because only a few of these ancient groups survived, humans are much less genetically diverse than other primates, even though there are many more of us on the planet. Ever since researchers discovered in the 1970s that humans lacked the genetic variation expected of our population size, they have proposed that our ancestors went through a big squeeze: Volcanic eruptions, disease, or climate change created a population "bottleneck" that reduced the number of breeding adults to about 10,000 sometime in the past 100,000 years. But new genetic studies of ancient DNA from Neandertals have found that they and the last ancestor they shared with humans, about 600,000 years ago, also lacked much genetic variation, which would require at least three dramatic bottlenecks--an improbable scenario. Meanwhile, other studies have found that language differences restricted gene flow in recent times in Europe, suggesting that cultural barriers might have limited genetic diversity more consistently than occasional local bottlenecks.
Paleoanthropologists Jean-Jacques Hublin and Luke Premo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, tested this hypothesis by simulating how mating preferences alter gene flow between individuals in different groups. Genetic variability plunged when individuals required mates with the highest degree of cultural similarity, the team reports this week in The Proceedings of the National Academy of Sciences. Conversely, genetic diversity increased when individuals were less selective about their mates--as is the case in chimpanzees or gorillas, which mate whenever possible with individuals from other groups.
Hublin and Premo propose that if human ancestors selected mates from similar backgrounds, there would have been a lot of inbreeding within different populations, restricting the flow of new mutations to other groups. "If these guys on the other side of the river spoke a different language and had different weapons, you would not try to mate with them or they might kill you," says Hublin. Over time, most populations went extinct, allowing the genes of only a few groups to proliferate, further erasing genetic diversity.
Researchers who have long worked on this problem are eager to test the new hypothesis in living hunter-gatherers. Paleoanthropologist John Hawks of the University of Wisconsin, Madison, for example, plans to ask his students to determine whether there's more intermarriage between hunter-gatherer groups that live close together and, therefore, are likely to have similar cultures. Biological anthropologist Henry Harpending of the University of Utah in Salt Lake City also likes the new explanation for the missing mutations: "It is time that human population geneticists recover from waving the magic wand of 'bottleneck' to try to explain everything."
It's crap science...just like global warming.
There are a lot of reasons that hooman beans are divided as they are but I seriously doubt tattoos are one of them.
I guess humans were the only creatures that were affected by the calamities. The moron scientist can never admit that man and monkeys aren’t related.
Talking to a friend last night...The difference between man and beast...A lion or whatever beast...remains the same forever. He does not “upgrade”. Only humans upgrade and “progress” in sustaining themselves....always looking for the better mousetrap.
Sorry, but the scientific evidence says they are, and with DNA analysis these days, we can say exactly how closely. The only "morons" in the equation are people who say they aren't related.
It’s all fun and games until they found the blond guy in the Chinese graveyard.
Somehow they never just get it right.
Time will tell who is a moron. ;0)
Notice how they carefully dance around what is by far the most likely reason most groups went extinct.
The survivors wiped them out. But in today's world we're supposed to think war and massacre was invented by white men, mostly Americans.
Old question , If we came from monkeys How come there are still monkeys? I am not refuting scientific evidence one way or the other, just asking, and why, then, are the species of monkeys and humans that survived so different? ( not counting some of my kinfolk in East Texas :) )
You got it wrong. We didn't come from monkeys. Humans and apes descended from a common ancestor. That common ancestor is extinct.
Maybe some of these “educated” people came from monkeys. A lot is written in the Bible about them. ;0)
LOL. Is this what he meant to say?
These people here?
I don’t know, have you seen some of the pierced, tatooed and scarified haridans that pass for females in the young hip culture?
They were the only group of Indo-Europeans that went east from the their ur-heimat north of the black sea. All the other groups went north, west, south, or southeast. Maybe they just wanted to be different.
If you had read the article you would have known that the Max Planck Institute for Evolutionary Anthropology is in Leipzig, Germany
And it is attitudes like yours that are driving scientists out of this country. The last thing we need is a brain drain of scientists like this. Perhaps you anti-science types could leave instead? That would be a far better trade.
Two words: imagio Dei