Skin color as evidence of natural selection

In this TED talk, author Nina Jablonski (Skin: A Natural History) suggests that whenever someone demands proof of evolution by natural selection, you should roll up your sleeve and show them your skin color. You carry this evidence around with you every day. You should point out that skin color changes depending on where one's ancestors lived. Check out the dramatic world map image at about 4:20 of the video. Darker skin colors can be found near the equator and lighter skin colors abound in higher latitudes. There is a fundamental and undeniable relation between skin color and latitude. But that is just the beginning of her story. We all have melanin: nature's sunscreen. It protected equatorial people from harmful UVB rays, but nonetheless allowed their skin to produce vitamin D, which is now recognized as essential for proper skin, bones and immune system function. When humans moved to higher latitudes, their skin tones lighted up to allow better production of Vitamin D. Jablonski warns, however, that the angle at which sunlight hits the earth at higher latitudes blocks most UVB rays, allowing only UBA rays which cannot produce Vitamin D. Hence, those of us living in the northern latitudes, no matter what our skin color but especially those of us who work indoors, are at risk for lack of vitamin D. She urges doctors to do a better job warning patients in higher latitudes about the potential damage to skin, bones and immune system caused by their lack of vitamin D.

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Putting our close genetic relationship to chimpanzees into perspective

Genomics Professor Katherine Pollard explored the genetic basis for being human in a video presentation titled "What Makes Us Human. Here a rather dramatic announcement from her talk:

Mouse and rat actually have a common ancestor longer ago than human and chimp, and some people will be surprised by that. They will say, "We are so much more different than a chimp . . . mouse and rat must be pretty similar." Actually mouse and rat on average are much more different from each other than we are from a chimp, and that's sort of a humbling fact to keep in mind.
We're not exactly like chimpanzees, of course, but there are quite a few overlaps (as well as differences), which Pollard explores beginning at the 4-minute mark. Surprisingly, young chimpanzees have a better competency in counting and numbers than young humans. At the 11-minute mark, you can see that the human genome is 95% similar to that of a chimp (or 99%, depending on how you define similarity), and that it is 28% similar (or 89%, depending on definition of similarity) to the genome of a mouse. [More . . . ]

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Richard Dawkins discusses the Greatest Show on Earth

In this Fora.TV video of a talk he gave at U.C. Berkeley, Richard Dawkins discusses his most recent book, The Greatest Show on Earth. In the early minutes of the talk, he explains why fossils are "icing on the cake" and he illustrates the "problem" with gaps by use of a humorous story. At minute 43:00, Dawkins explore the anthropic principle. At minute 49:00, Dawkins comments on the use of the word "why," as part of his comment on the question "Why are we here?" He explains: It's no more deserving of an answer than the question: "Why are unicorns hollow?" Dawkins also comments on the mechanism the creates conscious pain at minute 52:00, before declaring his own attempt to explain it to be incoherent. On the likelihood of a random mutation improving an organism, Dawkins points out that it is highly unlikely: "There are many more ways of being dead than alive." This video offers lots more engaging back and forth in the comments portion, following the main presentation. [More . . . ]

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Capitalism under the microscope

Annie Leonard has passionately researched and written a book she titles: The Story of Stuff: How Our Obsession with the Stuff Is Trashing the Planet, Our Communities, and Our Health-and a Vision for Change (2010). I haven't yet finished her book, although I'd like to post on one point she strongly makes early on, a point that is the elephant in the room regarding most discussions of the American way of life. It is a topic not far from the hearts of the many free market fundamentalists out there. The topic is whether it's time to put capitalism under the microscope. Here's what Leonard has to say:

[There is no doubt we will reach the planet's carrying capacity; we're heading in that direction now.... a big part of the problem we face today is that our dominant economic system values growth as a goal unto itself, above all else. That's why we use the gross to metric product, or GDP as a standard measure of success.... All right. Are you ready? I'm going to say it: this critique of economic growth is a critique of many aspects of capitalism as it functions in the world today. There. I said the word: "capitalism." It's the Economic-System-That-Must-Not-Be-Named. When writing the film script of The Story of Stuff, my intent was to describe what I saw in my years on the trail of trash, visiting factories and dumps and learning about how things are made, use, and thrown away around the world. I certainly didn't sit down and figure out how to explain the flaws of capitalism. It was trash, not economics, that was originally on my mind. So at first it took me by surprise that some commentators called the film "an ecological critique of capitalism" or "anti-capitalist."... it turns out that a hard look at how we make and use and throwaway Stuff reveals some pretty deep problems caused by core functions of a specific economic system called capitalism. There's no way around it: capitalism, as it currently functions, is just not sustainable.... Yet, in the United States, were still hesitant to broach this unmentionable subject, fearful of being labeled unpatriotic, unrealistic, or insane. Elsewhere in the world, there's a widespread recognition that some aspects of capitalism aren't working well for the majority of the world's people or for the planet; people talk about it openly.... Can we put capitalism on the table and talk about it with the same intellectual rigor that we welcome for other topics? Can we examine the failures of capitalism without falling into generations-old stereotypes and without being accused of being un-American? Refusing to talk about it doesn't make the problems disappear. I believe the best way to honor our country is to point out when it's going astray, instead of sitting here silently as many economic, environmental, and social indices worsen. Now would be a good time to start looking at what we could do differently, and what we could do better.... The belief that infinite economic growth is the best strategy for making a better world has become like a secular religion in which all our politicians, economists, and media participate; it is seldom debated, since everyone is supposed to just accept it as true. Why are so few people willing to challenge, or even critically discuss, an economic model that so clearly isn't serving the planet and the majority of its people. I think one reason is that the economic model is nearly invisible to us. ... [W]e tend to forget that were viewing the world through the paradigm, like it's a pair of contact lenses.... before we can change a paradigm, we need to identify it as a paradigm rather than assume it is truth. [Starting at page xviii]

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