Evolution

Show Me The Science Month Day 16 Black wolves look like creatures out of frightening fairy tales, but their black color actually came from pet dogs. Today's evolution paper is about a potentially beneficial mutation for black coat color picked up by wolves as the result of interbreeding with dogs. This story got some press, so it may sound familiar, but here we're going to focus on just how scientists could know where the black color gene came from. This research is a great example of the genetic sleuthing that's now possible with easy, affordable DNA sequencing. The basic story is this:…

Show Me The Science Month Day 15 What happens when a big chunk of your genome is accidentally copied? Bad things could obviously happen when when sudden and dramatic changes are made to your genome (which is why we wear sunblock on the beach and lead shields when getting X-rayed). Recent studies have found that accidental duplications in the genome (which can change the copy number of sets of genes) are involved in a growing list of diseases, including autism, psoriasis, and susceptibility to AIDS. And yet we also know that big DNA duplications aren't always harmful, because we can find…

       “The Extended Phenotype – The Long Reach of the Gene” is the book Richard Dawkins wants you to read “if you read nothing else of mine” because “It is probably the finest thing I shall ever write.” It purports to be about science, for scientists, yet at the very beginning there is a quite remarkable disclaimer. Dawkins warns the reader that the book contains nothing new, that it is “unabashed advocacy”, (in other words a mere personal opinion) and that it contains no hypotheses that are testable. In short, the book is declared from the outset to be non-scientific.…

Sunday Science Book Club, February 15 2009 Monkey Girl: Evolution, Education, Religion, and the Battle for America’s Soulby Edward HumesHarperCollins, 2007 It is rare for the world to see born on one day two towering individuals whose imprint on history is strong enough to be noted around the world 200 years later. Abraham Lincoln successfully saw the United States through a near-fatal convulsion, whose early symptoms had been palliated but not cured at the nation’s founding; the after-effects have reached all around the world. Charles Darwin, more than anyone else in the 19th century, put…

Adaptation is one of the driving forces behind evolution, along with selection and the appearance of new species, say a group of Ludwig-Maximilians-Universität München researchers, but they say that the interpretation familiar since Darwin - these processes increase the "fitness" of the species overall, since, of two competing species, only the fittest would survive - is actually a case of the fittest being the 'weakest'  most often. The extinction of species is a consequence of their inability to adapt to new environmental conditions, and also of their competition with other species,…

Today is Darwin Day. I didn't think I'd participate in this particular internet adventure. It looked like a lot of fun, Hank and Adaptive Complexity made sure of that, but it would be a long stretch to talk about the geometry of our planet let alone astrophysics and call it evolution just to join the party. Then I discovered Marv Lyon and his philosophically tinted evolutionary art work. Marv simply asks where do all the DNA go when species go extinct. A valid question for evolutionists and scientists in general. Marv communicates his concerns for endangered animals - and their DNA -…

It's the big day, the Darwin Bicentennial, so what are you going to read? You should start by checking out the interesting evolution pieces we've got here on the site, laid out on our Darwin Day Page. But this page isn't just about Scientific Blogging, it's about all scientific blogging around the web. If you have a blog, you've written something about Darwin or evolution, and want to participate (and have a chance to win a cool complete three volume set of The Life and Letters of Charles Darwin, printed in 1887), follow the link and see how to join in by adding the Darwin Day 2009 Badge.…

Coming up on Darwin's birthday, a lot is written about natural selection by non-biologists because opponents of evolution prefer to believe that biology stopped in 1859.  Criticizing Darwin and Natural Selection is a lot easier if you ignore the 20th and 21st centuries. And that's okay, if the goal is a culture war rather than a science discussion, because even in Darwin's time it wasn't all balloons and ponies for Natural Selection.  It was years later that evolutionary biology got help from an understanding of genetics and Natural Selection became accepted after rigorous…

The central dogma of Molecular Genetics is that information flow is unidirectional:  DNA to RNA to PROTEIN.  That is, DNA holds the blueprints, RNA is the messenger, and Proteins are the constructed functional units of life. This dogma seems to hold for most of the species on the planet.  From bacteria to humans to insects, the central dogma acts as a unifying theory of life’s architecture.   But, there are a few key exceptions. The first is that in some viruses, there is no DNA at all!  Instead, they used RNA exclusively for their coding.  Among these are…

Roughly 10 million years ago, a major genetic change occurred in a common ancestor of gorillas, chimpanzees, and humans. Segments of DNA in its genome began to form duplicate copies at a greater rate than in the past, creating an instability that persists in the genome of modern humans and contributes to diseases like autism and schizophrenia. But that gene duplication also may be responsible for a genetic flexibility that has resulted in some uniquely human characteristics. "Because of the architecture of the human genome, genetic material is constantly being added and deleted in certain…