One downside of our office's mandatory winter break is the fact that it's just not possible to give all the cool research coming out around the holidays the attention it deserves. I was really saddened not to have time to write something about evolutionary biologist David Kingsley's recent Science paper about an intriguing fish, the threespine stickleback. The thumb-sized prickly fish is a great model of evolution because of the many ways its map of protective spikes changed when melting glaciers 10,000 years ago allowed it to greatly expand its range. After this mass colonization, individual populations quickly became isolated as water connections between individual lakes and streams dried up, and the groups of fish were left to host their own evolutionary parties, complete with gatecrashers in the form of never-before-encountered predators.
Fortunately NPR's Joe Palca was around to pick-up the slack for me. He summarized the research--which shows that evolutionary changes can arise not just from mutations in genes, but also in the on/off switches that control gene activity-- on All Things Considered on Dec. 18.
A written summary of the audio file, and additional web assets can be found here. If you're curious about what the pelvic spine looks like, check out this 3D movie from Kingsley's lab. Otherwise, just feast your eyes on this very cool photo of one of their not-so-cuddly lab animals. Here the bones of the fish have been stained with a red dye, the better to view changes in spine structure. Go sticklebacks!!
Photos courtesy of Kingsley laboratory