New Ancient Human Identified

krou writes "Working on a finger-bone that was discovered in the Denisova Cave of Siberia's Altai mountains in 2008, Johannes Krause from the Max Planck Institute for Evolutionary Anthropology and colleagues managed to extract mitochondrial DNA. They compared it to the genetic code of modern humans and other known Neanderthals and discovered a new type of hominin that lived in Central Asia between 48,000 and 30,000 years ago. Professor Chris Stringer, human origins researcher at London's Natural History Museum, said, 'This new DNA work provides an entirely new way of looking at the still poorly-understood evolution of humans in central and eastern Asia.' The last common ancestor of the hominid (dubbed 'X-Woman'), humans and Neanderthals seems to have been about one million years ago."

Summary is slightly optimistic.

[JoshuaZ]

Yes, they definitely extracted mitochondrial DNA (that's DNA that isn't in the nucleus but is rather in the mitochondria and is only passed down by your mother). Yes, the DNA looks different enough that they're pretty sure this isn't any form of contamination from modern samples (always a worry when doing this sort of thing). However, it is far from clear that this DNA is belonged to another species. There are multiple possible other explanations which could make this not another species. The details are a bit technical, but anthropologist John Hawks has a piece on his blog laying out the basic issues- http://johnhawks.net/weblog/reviews/neandertals/neandertal_dna/denisova-krause-2010.html [johnhawks.net]. A slightly more lay-oriented piece by Carl Zimmer (the writer for Science Times and author of the very excellent book Parasite Rex) is also worth reading: http://blogs.discovermagazine.com/loom/2010/03/24/the-x-womans-fingerbone/ [discovermagazine.com]. The bottom line is that concluding that this is a new species is as of yet very premature.

Re:It's pretty amazing

[Anonymous Coward]

From the linked article:

Most scientists believe there is insufficient data to resolve the contributions of heredity and environment.

Further, races are social constructs. As in "constructed by societies." As in "not based in actual biology." There are more genetic differences among members of any given ethnic group than there are between members of any two ethnic groups. If you ever actually acted on any interest in sociology, much less studied it, you would know this.

All this points to the argument that differences in mental aptitudes displayed in aggregate by various "races" in the U.S. are primarily a cause of each race's traditional socioeconomic status, i.e., how members of each "race" are treated and raised by agents of social control (esp. teachers) determines their evident mental prowess.

Re:Summary is slightly optimistic.

[DavidD_CA]

The summary doesn't say anything about this being a new species. The word "species" doesn't even appear.

And in the article, the first use of the word "species" says this:

However, for now, the researchers have steered away from describing the specimen as a new species.

And this:

Other experts agreed that while the Siberian specimen may be a new species, this has yet to be shown.

I'm all for shooting down /. summaries and sensational headlines, but this appears to be right on.

Re:where are the tin-foil-hats?

[Sique]

The team was actually pondering that this may be a case of contamination. But -- which mitochondrial DNA contamination will yield a result that shows a divergence that is larger than Homo sapiens sapiens vs. Homo sapiens neanderthalensis, but not large enough for Homo sapiens sapiens vs. Pan troglodytes?

PS: The Neanderthal is a narrow valley between the towns of Erkrath and Mettman, called so in memoriam of the Calvinist church teacher and hymn writer Joachim Neander [wikipedia.org]. I wonder what he would have to say about a human subspecies indirectly named for him.

Re:It's pretty amazing

[Anonymous Coward]

Of course, this is not true.
http://en.wikipedia.org/wiki/Lewontin%27s_Fallacy
"Lewontin argued that because the overwhelming majority of human genetic variation (85%) is between individuals within the same population, and about 6–10% is between populations within the same continent, racial classification can only account for between 5–10% of human variation"
"As Edwards showed, even if the probability of misclassifying an individual based on a single locus is as high as 30% (as Lewontin reported in 1972), the misclassification probability based on 10 loci can drop to just a few percent."

What in realty is "-One locus is not enough to racially classify an individual" - as if someone really believed this - has destorted into the the lie of the grand parent.

When looking at a few hundred loci, misscalssification is in the tenth of percenteges.
http://www.sciencedaily.com/releases/2005/01/050128221025.htm
"The study is by far the largest, consisting of 3,636 people who all identified themselves as either white, African-American, East Asian or Hispanic. Of these, only five individuals had DNA that matched an ethnic group different than the box they checked at the beginning of the study. That's an error rate of 0.14 percent."

Re:It's pretty amazing

[spiralpath]

The sheer ignorance of modern anthropology I see on Slashdot is unnerving. So many people on here assume that their enculturated worldview equals science.

Race is a social construct. Phenotypical differences are one axis along which race is constructed, but it is not the only axis, and in some contexts it is not even the most important. As an example, you can also tell the "race" of a person if you talk to them on the phone. This obviously has nothing do with biology.

Although race as a system of scientific categorization started in European thought during the Enlightenment, it has seriously decreased in scientific merit because of genetics. Today, physical anthropologists think in terms of "clines." Unfortunately, because of the impact of European empires and their hegemony, race as a system of categorization persists in various incarnations throughout the world. This system is perpetuated by a wide variety of structural institutions and the uneducated public.

You can tell races apart because you are conditioned to detect certain characteristics which you associate with an arbitrary categorization of people. These arbitrary categorizations gradually accrued social and cultural capital in YOUR culture. This does not mean they are based in any kind of genetic reality.

Re:It's pretty amazing

[corbettw]

Does his head have an occipital bun? Do his ribs flare out at the waist? Are his hips set back further than yours? Do his legs bow outward? No? Then he doesn't look like a neanderthal, he just looks like a guy with lots of testosterone. Doesn't sound like someone I'd want to tease all the time.

Re:Hello? Anybody here?

[wastedlife]

I'm not an anthropologist, but I'll take a swing.

This is significant, because they discovered a species of hominin that branched off before Neanderthal but may have co-existed. This can provide some more insight to our own development. How many other hominins branched off but co-existed with our ancestors? Why did they die out while our ancestors survived? Did we fight them, hunt them, cooperate with them, merge with them, out-compete with them, or some combination of the above? Does it have a major effect on normal people's lives? Probably not, but it is a pretty big discovery for science and genetics.

Also, there is no such thing as "the missing link". Evolution is always happening, all fossils are is a snapshot of that species at the time of it's death. Since not everything leaves a fossil when it dies, all of the gaps will never be truly filled. However, the gaps continue to shrink as more and more evidence is found, and that is the best we can hope for, to keep expanding on our knowledge.