Artist's impression of a Neanderthal hunter. New evidence suggests the Neanderthals and modern humans interbred.
Credit: American Museum of Natural History
SYDNEY: Modern humans contain a little bit of Neanderthal, according to a new theory, because the two interbred and became one species.
The theory is the latest addition to the ongoing debate about what happened to this early species of human.
In a paper published this week in the U.S. journal Proceedings of the National Academy of Sciences, a team of European researchers report a "mosaic of modern human and archaic Neanderthal features" in 30,000 -year-old human fossils from Romania.
Co-author Erik Trinkaus from Washington University explains: "[Some] closely related species of mammals freely interbreed, produce fertile viable offspring, and blend populations." This is what appears to have happened with Neanderthals and modern humans, he says.
Shorter and stouter than modern humans, but with larger brains, Neanderthals lived in Europe, central Asia and the Middle East for about 170,000 years before disappearing between 33,000 to 24,000 years ago.
Their extinction coincided with the migration of modern humans out of Africa and across Europe. Few mysteries in the history of human ancestry have been as hotly debated as what caused the extinction of the Neanderthals.
Some scientific theories have Neanderthals dying out because they were less well-adapted to the climate changes that occurred across Europe at that time. Others cite evidence of a more brutal end, in which Neanderthals were slaughtered by modern humans.
This new study helps to settle the controversy. According to the researchers, the populations probably blended together through sexual reproduction. "Extinction through absorption is a common phenomenon," says Trinkaus.
The human remains were found in Pestera Muierii ('Cave of the Old Woman'), an elaborate cave system in Romania. First uncovered in 1952, the fossils remained poorly dated and largely ignored until recently.
Using carbon dating techniques, Trinkaus and colleagues found that the remains were 30,000 years old. Their analysis of the bones revealed diagnostic skeletal features of modern humans, including smaller eyebrow ridges, very narrow holes where the nostrils join the skull, and a shin bone that is flat on one side and concave on the other.
However the mostly human skeletons also possessed distinct Neanderthal features; features that were not present in ancestral modern humans in Africa. These include a large bulge at the back of the skull, a more prominent projection around the elbow joint, and a narrow socket at the shoulder joint.
Further analysis of one skeleton's shoulder showed that these humans did not have the full set of anatomical adaptations for throwing projectiles, such as spears, during hunting.
According to the researchers, this mixture of human and Neanderthal features suggests that a complicated reproductive scenario existed as humans and Neandertals interbred. The hypothesis that the Neanderthals were simply replaced should therefore be abandoned, they suggest.
Trinkaus says we may carry some of the genetic legacy of the Neanderthals within us. However it would be difficult to determine which of us are more closely related to the Neanderthals: "there has been 30,000 to 35,000 years of human evolution since then," he says.
Humans and neanderthals interbred. Reply
Dude. Our genomes are pretty much the same. And yes Europeans do have a distinctive genome from Africans. Their skulls possess different features that are distinctive and it has been shown that certain characteristics in skin from DNA are shared between Africans and Asians, but not by Europeans.
What if a chimp with down
What if a chimp with down syndrome breeds with a human with down syndrome. They will have the same chromosomes as the chimp will have 47 and human will have 47.
email me on datdean300@hotmail.com on this topic.
Neandertal Claims Are Unscientific
The whole proposition of trying to decide the Neandertal controversy--as to whether they interbred with modern humans or became completely extinct--on the basis of subjective, skeletal analyses is improper. This is not science!
In a more objective approach, genetic studies by Paabo Svante have concluded that the Neandertals were not capable of interbreeding with Homo sapiens because they were a different species, Homo neandertalensis. And, currently, other genetic studies are under way to either validate or refute Svante's research.
Considering this, why is Erik Trinkhaus so eager to end the controversy on the basis of some subjective analyses, ruling in favor of interbreeding? Is it borne out of sympathy for the Neandertals? Is it a desperate attempt to undermine the Out-of-Africa theory of modern human origins. Like his co-conspirator, Milford Wolpoff, in this matter, Trinkhaus has no only lost respect and credibility, but he seems to have lost his mind.
Shared Traits
Like Erik Trinkhaus (http://news-info.wustl.edu/pub/libs/images/usr/149_h.jpg), I once had blond/red hair and have always wondered what the 'weird' projection (inion) was at the base of my skull. I always wondered where my green eye-color, freckles, unibrow, elbow notch, and intelligence came from prior to my Scottish ancestry; maybe Dr. Trinkhaus is similarly motivated, maybe not.
As far as I know these shared traits evolved either separately in each group or were transferred between the groups. I'm willing to accept either answer and hope that the Neanderthal DNA sequencing will shed further light on the origin of my many, rare traits.
wikipedia
Based on an Oxford University 2001 study of the gene that results in red-headedness,[15] some commentators speculated that Neanderthals had red hair and that some red-headed and freckled humans today share some heritage with Neanderthals.[16][17] A 2007 study analysing Neanderthal DNA found that some Neanderthals were indeed red-haired, but the mutation to the MC1R gene which caused red hair in Neanderthals was different from that found in modern individuals, ruling out that red hair is a trait inherited from the Neanderthals.
you are one , helluve wise
you are one , helluve wise man . Joh
Being Genetically Different Doesn't Ruke Out Interbreeding
Just because 2 species are genetically different does not rule out the possibilty of them interbreeding.
Lions and Tigers are 2 genetically different species, and have historically remained so because they exist on seperate continents. However under artifical circumstances (ie. in captivity) they not only interbreed to produce live offspring (Liger and Tigon), but these offspring can then also breed with Lions and Tigers to produce live offspring (Li-liger, Ti-liger, Li-Tigon and Ti-tigon).
Although not common, it is definitely possible. Surely the same thing could have been possible between Neanderthals and Homo sapiens.
Ligers
In order for a liger to interbreed it always has to be female. WHile it is possible that this can occur and it has happened the offspring will always be frail. All of the documented cases of liger or tigon hybrids were raised in captivity. If it did happen it would have been an extremely rare event and the probability of that offspring surviving to adulthood would be very very low.
Neanderthal Claims are unscientific?
I find your statement to be unscientific! You ignore MCPH1 that, by all genetic testing & standards, "introgressed" into the human genome ~37,000 yrs ago. Because this 1.1 million yr old gene suddenly appeared in a 200K yr old species, in the mid east & rose to a positive selection of 70% of the World population, it strongly suggests an archaic source.
Let's be scientific...
Well before we credit Paabo Svante, let's wait until there is more genetic research done on another prehistoric individual.
Other than that, how does one explain a "modern" Neanderthal with a very "human" chin- amongst other features, but very Neanderthal jaw dimentions- as found in Portugal, 3,000 years younger than the youngest Neanderthal remains?