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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."
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. 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/. The bottom line is that concluding that this is a new species is as of yet very premature.
You are correct that there's evidence for there being correlation between mental abilities and race. But that doesn't mean it is at all genetic. Much of it is almost certainly cultural and environmental. For example, if you get less nutrients growing up you likely aren't going to be as smart as someone else who does get enough nutrients. That's because early brain growth is determined in part by how much resources the brain has available. Similarly, certain cultures have games and habits with young children that may encourage certain forms of mental development or practicing certain skills. Moreover, some types of intelligent tests are very culturally based (there are some fascinating cross cultural studies about how people naturally organize things into groups. While in most Western societies we consider organization into functional categories to be ideal and consider people not as bright if they have trouble, in many other societies and even some Western societies, given a set of objects they will try categorize by which groups of objects can be used together. The classic example of this is giving a bunch of tools and a bunch of possible things that the tools can modify. The "correct" Western response is to group into tools and non-tools. But in some cultures they instead group into which are connected to relevant processes). So yes, such correlation does exist, but there's no strong evidence that such correlation actually means much at all.
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.
Uh... credentials mean nothing. Refuting a statement with facts means more.