Todd's Blog

  There's a fascinating new research paper from last week's Science looking at large-scale trends in mammal skull shapes, and I'm still still thinking about it.  These comments are very preliminary. Authors Goswami and colleagues examined a sample of 322 mammal skulls covering the majority of mammalian diversity.  They analyzed changes in shape using 3D models of the skulls and landmarks to track how skulls differ from group to group and how they believe mammals have evolved over the last 100 or so million years on the conventional timeline.  They reach a few very interesting conclusions based on their results.  First, the highest rates of skull change in mammal "evolution" occur primarily at the base of the mammal tree, near the beginning of the Cenozoic.  Second, the highest rates of skull change among the mammals occur in groups like the whales, elephants, and sea cows.  Third, the lowest rates of skull change occur in the rodents and bats. That so...

Short answer: no. Long answer:  It's still no, but let me explain. As a biochemist by training, I've been interested in research on the origin of life for a long time.  I'm not talking about God speaking creatures into existence, either.  This research begins with the assumption that life emerged naturally from nonliving chemicals.  You might remember from high school biology hearing about Stanley Miller's experiment, where he zapped some ammonia, methane, and water vapor to make simple amino acids.  That experiment essentially jump-started the field of origin of life research, where scientists try all sorts of weird conditions to see if they can make biochemicals using random processes.   This research has not been successful.  Oh, it's definitely made progress of sorts.  Different sorts of chemicals have been formed, and we've found interesting organic compounds in space.  But no one has successfully generated a living system from any...