Futurepundit has an interesting post based on a new paper about so-called junk DNA. Only 2% or so of the human genome actually encodes protein sequences. The rest is a grab-bag of broken genes and virus-like sequences called mobile elements that hijack the cell’s DNA copying-machinery from time to time and insert new copies of themselves back into the genome. A pair of scientists have come up with some ideas about why organisms like us have junk-rich genomes, while bacteria have barely any. I was going to post on it until pre-Thanksgiving business overwhelmed me.
I’ll be talking about evolution on Tuesday at 12 pm PST/3 pm EST with Alan Stahler on KVMR in California. You can listen to the live webcast here.
It’s too early yet for reviews of Soul Made Flesh to start rolling in (it pubs in January 2004), so I’m still in an anxious state. But this is promising: The Daily Telegraph in London asked several leading writers to name the favorite book they read in 2003. Yesterday it printed the results. Steven Pinker chose Soul Made Flesh.
The glow of a beetle has inspired an elegant bit of evolutionary detective work that appears in the Proceedings of the National Academy of Sciences. Americans like myself are familiar with fireflies, but in the tropics the night is also illuminated by beetles. When Darwin came to Brazil on the Beagle, he amused himself by noting how the beetles were “rendered more brilliant by irritation.” Naturalists have gotten a bit more sophisticated at studying beetles since then. They now know that the male beetles use the light organs on their underside to get the attention of females that are sitting in the trees and bushes; when the female sees a glow she likes, she registers her approval by flashing light organs on her back. (Fireflies do the same thing, but while they flash, the beetles give off a steady glow.) Scientists also know how the glow is made–a gene creates a protein called luciferase, which cuts up another protein called luciferin, releasing photons at a distinctive frequency. Depending on the species, the frequency is different.
Texas may be off the hook for now, but Razib at Gene Expression observesthat some medical students at the University of Oslo are lobbying for anti-evolution lectures. I guess I’ll try not to be in Norway if I need antibiotics.