More on Neanderthals

Earlier this year, I posted on a comprehensive article regarding Neanderthals published by National Geographic. In the August, 2009 edition of Scientific American, you can find considerably more information on our Neanderthal cousins. One of the most interesting things about Neanderthals is that they survived for nearly 15,000 years after modern humans moved into Europe (modern humans entered Europe about 40,000 years ago). Some scientists suggest that modern humans did not necessarily kill the Neanderthals directly, but that "the Neanderthals ended up competing with the incoming moderns for food and gradually lost ground." The reason they might've lost ground is that modern humans were more flexible about what they could eat--they were able to survive off of smaller animals and plant foods. Anthropological evidence suggests that Neanderthals focused mainly on large game, which often became scarce, and which prevented a division of labor among Neanderthal men, women and children. Neanderthals also needed a lot more calories than modern humans. Paleoanthropologist Leslie Aiello described them as follows: "Neanderthals were the SUVs of the hominid world." Evidence also suggests that Neanderthals were intellectually active. Neanderthals probably had language (based upon the fact that they decorated their bodies with jewelry and pigment, which were often used as a proxy for language). Further, recent analysis of Neanderthal DNA shows that they carried "the same version of the speech enabling gene FOXP2 that modern humans carry." The article indicates that a full analysis of Neanderthal DNA is likely out this year, and that it is expected to shed far more light on what it meant to be a Neanderthal

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David Attenborough illustrates the tree of life in six minutes

In this six minute Youtube video, David Attenborough illustrates this deep truth: All Life is Related. This is an especially elegant story these days, where so many people are looking for so many ways to divide humans from the other animals, and to divide many groups of human animals from other groups of human animals. BTW, for anyone who hasn't yet viewed any of David Attenborough's nature DVD's they are all thought-provoking and beautifully filmed. They aren't just spectacular videos of animals in the wild; they also contain Attenborough's elegant descriptions and explanations of what you are viewing. One of Attenborough's more recent efforts is Planet Earth (a STEAL for $36). I have just ordered, but have not yet viewed his most recent series, Nature's Most Amazing Events.

Continue ReadingDavid Attenborough illustrates the tree of life in six minutes

U.S. Supreme Court: no federal right to review DNA evidence

Here's the context: 240 convicted felons have now been proven to be totally innocent thanks to analysis of DNA evidence. Many states have enacted laws giving prisoners the opportunity to obtain DNA analysis of critical evidence used at their trials in years past. The U.S. Supreme Court has now ruled, however, that there is no federal constitutional right to DNA evidence that could exculpate a convict.

The Supreme Court said Thursday that a convicted rapist has no constitutional right to test biological evidence used at his trial in Alaska years earlier, leaving it to the states to decide when prisoners get access to genetic evidence that might prove their innocence . . .

Dissenting liberal justices and advocates for prisoners who seek genetic testing complained that the court is penalizing a small group of inmates who lack access to a simple test that would conclusively show their innocence, or reaffirm their guilt.

Here is the full opinion, District Attorney's Office v. Osborne. Justice John Roberts (supported by the Court's conservatives) wrote the majority opinion, concluding both of the following:

A) "DNA testing has an unparalleled ability both to exonerate the wrongly convicted and to identify the guilty." and

B) If you were convicted in one of the handful of states that aren't willing to analyze the DNA evidence of your case, you're screwed. Case over. Too bad for you. Why? Because it would mean more work for the federal judiciary.

Way to go, Justice Roberts. You are compiling quite a track record of refusing to look out for the oppressed and powerless. And see here and here. For more information, visit Project Innocent.

Continue ReadingU.S. Supreme Court: no federal right to review DNA evidence

Flimsy eyewitness testimony

You often hear people claiming that the case is strong because there was an "eyewitness." It's becoming increasingly clear, however, that eyewitness testimony is often worse than useless. Modern DNA testing has exposed just how weak eyewitness testimony can be, as presented Radley Balko, in Reason:

Law and Human Behavior, false eyewitness testimony contributed to 77 percent of the 230 wrongful convictions exposed by DNA evidence over the last decade (the number of exonerations has grown since the study was conducted). These of course are only those cases for which DNA testing was available, which are usually murder and rape cases—crimes for which, generally speaking, there is also usually other evidence available. In crimes where investigators are more likely to rely only on eyewitnesses, robberies or muggings, for example, it’s likely that the problem is even more pronounced.

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Diminishing races, growing family

In the January 22, and 2009 edition of Nature (available only to subscribers online), Aravinda Chakravarti explains that our simplistic notions of "population" and "race" will need to be revised as we enter the age of "personal genomics." Chakravarti teaches at the Johns Hopkins University School of Medicine. Traditionally, we've used geological records to trace our family histories. We are now approaching a time where we will be able to use DNA databases. Whereas our traditional human records take us back several hundred years, our genomes will allow us to explore our ancestry for hundreds of thousands of years. Chakravarti argues that we will be entering unknown territory riddled with surprises and stretching the meaning of the word "family." How close knit is our human "family"?

All living humans are related via a set of common ancestors who lived in Africa about 200,000 years ago. Other studies have since shown that the world beyond Africa was settled even more recently. From 100,000 years ago, descendants of our African forebears spread out to populate other continents . . . the striking implication of this is that all living humans are mosaics with ancestry from the many parts of the globe through which our ancestors trekked. In other words, each of us has around 6.7 billion relatives.

Chakravarti points out that our genealogy-based record-keeping is often riddled with error. It fails to indicate our interrelatedness to each and every other human being, for example. Further, evidence shows that at least one out of 20 people do not know the identity of their genetic father. Thanks to the falling cost of examining entire human genomes (Chakravarti indicates that it has fallen 1000- fold or more), we now have abilities we could only have dreamed of a few decades ago. Personal genomics might well destroy our simplistic notion of "race." Human populations are not intact groups. There is no such thing as genetically characterized racial categories. We are all "multiracial, related to each other only to a greater or lesser extent." Detailed surveys are making it clear that there is no such thing as a discrete racial group. Rather, it is clear that there is a "continuity in variation across the globe, not abrupt transitions between population-specific sequence patterns." Personal genomics would allow us to focus on individual human beings, instead of artificially constructed "racial" populations.

Genome-wide studies ... could result in the individual identity and kinship coming to define populations rather than the other way around. We could test once and for all whether genetic race is a credible concept. This would be tremendously exciting. It is bound to stir up our deeply held notions of who we are, where we came from, our history and thus our politics. .. . it may be time for science to reshape the views of society. By dismantling our notions of race and population, we may better appreciate our common shared and recent history and perhaps more importantly our shared future.

I recently posted on the topic of whether science should study race and intelligence. I think this would be a worthy topic of science (just as is every other potential field of study), but I warned that our current definition of "race" is horribly muddled. We need to get clear on this term, if that is even possible. I found Chakravarti's article to be a refreshing reminder that there might not even be a worthy scientific definition of "race." In fact, it might well be that, once we look carefully at the evidence, we will find that there are actually 6.7 billion "races" out there. Or is it more accurate to conclude that there is only one human race?

Continue ReadingDiminishing races, growing family