Evolution

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In his book, Wonderful Life: The Burgess Shale and the Nature of History, Stephen Jay Gould speculated about an experiment of ‘replaying life’s tape’, wherein one would go back in time, let the tape of life play again and see if ‘the repetition looks at all like the original.’ Evolutionary biology tells us that it wouldn’t look the same; the outcome of evolution is contingent on everything that came before.   Scientists at the Instituto Gulbenkian de Ciência (IGC) in Portugal, New York University and the University of California Irvine say they have provided the first quantitative…
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"Raw materials were not an issue" for the evolution of the first life on earth, argues Henderson Cleaves, a researcher at the Carnegie Institution, quoted in Carl Zimmer's Science essay on origins of life research (subscription required for full text). There is good reason to believe that there were plenty of organic compounds floating around on the earth 4 billion years ago. The big problem, as Zimmer notes, is how you get from the primordial soup, Darwin's "warm little pond", to an organized, self-reproducing system. A key point to keep in mind when reading about this subject is that…
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That's because there is going to be so much great, non-technical writing in honor of Darwin's 200th birthday and the 150th anniversary of the publication of On The Origin of Species. We're going to have some great Darwin Day writing here at Scientific Blogging. Science magazine has started an entire blog devoted to the Year of Darwin, called Origins. Head on over there and add the feed to your reader; they're going to have some worthwhile reading (some of it on the blog, and some of it in the magazine itself - you'll need a subscription for those pieces).
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Whenever one discusses the underlying genetic influences on human behavior, one is opening themselves up to being labelled a determinist.  Part of the reason for that is a total misunderstanding of what the word “gene” actually means (not to mention the lack of understanding of the difference between a genotype and a phenotype).  But, it isn’t just the public that takes issue with the word “gene”.  So do some biologists, not least of which are geneticists, or in this case, molecular anthropologists. John Hawks goes into the discussion here, but in the end he favors keeping the…
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I just ran across a great population genetics blog, Selective Sweep, written by derele, a PhD student in Edinburgh. He writes in both German and English about genomics, population genetics, and Science 2.0. Recently he's started a interesting primer on population genetics - it's in German, for those of you who can read it (and you can always try Google's translation if you don't speak German). If you go to a scientific conference, it's immediately clear that science consists of big international communities, but unfortunately major science blogging communities (dominated by writers from the…
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If you read almost any science blog other than mine, you're probably aware of Brown University biologist Ken Miller's smackdown of Intelligent Design (ID) shill Casey Luskin, posted on Carl Zimmer's Loom: part 1, part 2, and part 3. At issue is the tired old concept of irreducible complexity, and it's amazing that after all this time, many ID advocates don't understand what the original point of arguing irreducible complexity was. ID advocate Michael Behe, in various publications including his book Darwin's Black Box basically argued that there are molecular systems inside of cells that, even…
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There are fossils of all shapes and sizes but we like dinosaurs because they're big and that means they could engage in terrific imaginary battles with other big things, like King Kong. You don't see natural history museums vying for fossil skeletons of prehistoric kittens, it's the Tyrannosaurus Rex fossils everyone goes after, whereas non-science people tend to go for little  squeaky things they can fit in their laps while they drive and talk on the phone.  Earth's creatures come in all sizes, yet we all sprang from the same single-celled organisms that first populated the planet…
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In an article for the Journal of Theoretical Biology, Herbert Gintis provides a model that shows that: “if an internal norm is fitnessenhancing, then for plausible patterns of socialization, the allele forthe internalization of norms is evolutionarily stable.” Further he posits that this view can be used to model Herbert Simon’s 1990 explanation of altruism.  Simon’s idea is that altruistic norms “Hitchhike” on the backs of the general tendencies of internal norms to be “personally fitness enhancing”. OK, cool, so what is an “internal norm”?  It’s a pattern of behavior that is…
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Bacteria often provide vivid examples ofhow powerful the forces of evolution can be.  In keeping with that,Hershberg, et al., in a paper published in PLoS, show that evolutionary forces may increase the number of drug-resistent strains of Mycobacterium Tuberculosis (MTB). They attribute the increase of these strains to both humandemographic conditions (global travel, urbanization, population growth)and genetic drift. This is a case when the intersection of evolution and of economicscan have an unsavory effect.  Every 15 seconds a person dies of MTB. Furthermore, we found that…
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Ian Ramjohn recently posted an interesting (but far too short) article on Scientific Blogging titled Competition and Coexistence in which he discussed various theoretical scenarios that could develop if a new species formed and began competing with its parent species for resources. It set me thinking about the whole concept of competition, in particular its alleged importance in evolution and the widely held assumption that competition is ever present, a constant, a given condition of existence. I revisited a similar discussion in The Selfish Gene in which Richard Dawkins used the example of…