Print 76 comment(s) - last by Paj.. on Sep 1 at 7:28 AM

Neanderthals and Denisovans, two archaic hominid species, have been shown by genetic tests to have interbred with human migrants in Europe and Asia.  (Source: Corbis)

Researchers speculate that such sexual attractions between the species were rare, but that the children were much more genetically fit, so came to dominate the population.  (Source: Google Images)

The highest rates of Denisovan DNA occurrence were found in the DNA of natives of Papua New Guinea.  (Source: Flickr)

The immune proteins our hominid relatives gave to us during interbreeding made us hardier and more resist to potentially deadly infections.  (Source: Paul de Bakker)
Turns out Europeans and Asians may be the least "genetically pure" homo-sapiens

It turns out that European DNA, like that of Asians and Africans, has traces of archaic hominids mixed in with the familiar Homo sapien-specific stretches.

The sequencing of the Neanderthal genome
 has led to some incredible discoveries -- among them, that humans were having sex with Neanderthals.  A pair of new studies has shown that Neanderthal genes aren't evenly distributed throughout the entire human population -- rather some populations have more or less of them.

A new study, whose senior author is 
Peter Parham, a professor of cell biology, microbiology and immunology at the Stanford University School of Medicine, examines how interbreeding with our closely related hominids led to a superior human immune system.

Svante Pääbo, director of the Department of Genetics at the Max Planck Institute for Evolutionary Anthropology and senior author on the paper [abstract] detailing the original Neanderthal genome draft, suggests that one of two possibilities occurred.  Either migrants to Asian and Europe broadly had sex with Neanderthals or just a few did, but whose progeny survived in greater numbers, passing on the early hominids' genetic material.  Researchers believe the latter explanation is more likely the case.

Humans are thought to have migrated from Africa around 67,500 years ago, spreading to Asia and Europe.  In these regions they encountered Neanderthals and Denisovans -- another archaic hominid, who they at least occasionally engaged in sexual intercourse with.  Interbreeding is thought to have occurred starting around 50,000 years ago.

Those hairy charmers passed something valuable along to the migrants -- improved immunity.  Many of Eurasians'  HLA genes -- fast evolving human immune system components -- are thought to have been "borrowed" from the Neanderthal and Denisovan genome.

It found that one Denisovan-derived gene -- HLA-A  -- was 95 percent likely to occur in residents of Papua New Guinea, 70 percent in residents of China, 50 percent in Europe, and virtually non-present in Africa.

The genes are thought to have conferred improved survival rates on the migrants, as they gained defenses against local diseases, which took their archaic hominid co-inhabitants millennia to develop.

Africans, who never personally interbred with the Denisovans and Neanderthals did receive a bit of these genes second hand, from migrants who returned to the region around 10,000 years ago.  And they are thought to have an even stronger and more diverse immune system, as they bred with other species of archaic hominids
, which were native to Africa.

Previous studies have shown that non-Africans have around 4 percent Neanderthal genes, while Melanesians -- natives of Indonesia and the surrounding islands -- also have 4 to 6 percent of their genes derived from the Denisovans.

The study on the project is published
 [abstract] in the prestigious peer-reviewed journal Science.

The new work could offer some additional explanation of why Native Americans may have been so susceptible to diseases brought to the New World by Europeans and Africans.  Native Americans may have missed much of the interbreeding opportunities.  Thus while they may be the most "pure" examples of Homo sapiens DNA, that may have proved fatal to many of them.

Comments     Threshold

This article is over a month old, voting and posting comments is disabled

RE: Hmm...
By mindless1 on 8/30/2011 9:28:15 PM , Rating: 3
You are a little deluded. The slaves brought over were picked to be the strongest men (better workers) and were those who survived horrible conditions in the galley of slave ships. Natural selection ensured that those who had the chance to rear children in this terrible period of history, were genetically gifted compared to most other people regardless of skin color. The same would have been true if Africans had kidnapped and enslaved Englishmen.

Everything you have written can no more be substantiated than the opposing points of view. That something "seems" like it agrees is not a PROOF that can be assumed while rejecting contradictory evidence.

Bah, this is a silly argument we're having and a true waste of time so I'll stop. Have a nice evening.

RE: Hmm...
By wordsworm on 8/30/2011 11:14:05 PM , Rating: 1
Huh... I wonder how they managed to breed them at all, then. I would have thought that some women were brought to America, too.

Evidence means nothing to you. Most just like the idea that God created folks the way they are rather than there being some fundamental biological reason why the races have evolved to have their unique characteristics.

You can examine any animal that has been bred for specific purposes and see how they exceed their counterparts in the wild in those specific regards. Humans are as much animal as any of them. We were not created from the image of God, God was created in the image of the men who invented him. It's a myth. We are animals. There's no reason to doubt that the men who were bred in captivity had time to improve certain characteristics beyond their natural counterparts. Their masters, on the other hand, bred amongst each other and often within the same family according to bloodlines. Those who were bred as slaves were bred according to the best characteristics. It's natural to see that the masters degenerated while the slaves improved. I don't agree with slavery. I am saying that we don't naturally make the best choices for ourselves. Those who are in the business of breeding for a purpose are much better at creating a Nietzschean superior race than those who choose according to money and possessions. They can also choose the best studs (in the literal sense) to procreate while often neutering those who were not.

In order to be objective, you sort of have to disregard the idea that facts and evidence don't give a damn about what we are comfortable with thinking or what is politically correct. It does not matter if I'm Caucasian, Asian, or any other race. It has no merit in a conversation about biology. What we would like to be true is rarely going to be true.

RE: Hmm...
By Spuke on 8/31/2011 12:04:27 AM , Rating: 2
The slaves brought over were picked to be the strongest men (better workers) and were those who survived horrible conditions in the galley of slave ships.
Natural selection indeed brought the strongest of the strong over from Africa BUT slaves were indeed "bred".

"We can't expect users to use common sense. That would eliminate the need for all sorts of legislation, committees, oversight and lawyers." -- Christopher Jennings

Most Popular ArticlesAre you ready for this ? HyperDrive Aircraft
September 24, 2016, 9:29 AM
Leaked – Samsung S8 is a Dream and a Dream 2
September 25, 2016, 8:00 AM
Inspiron Laptops & 2-in-1 PCs
September 25, 2016, 9:00 AM
Snapchat’s New Sunglasses are a Spectacle – No Pun Intended
September 24, 2016, 9:02 AM
Walmart may get "Robot Shopping Carts?"
September 17, 2016, 6:01 AM

Copyright 2016 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki