Running! Photo by andronicusmax.

• If you’ve got ’em, use ’em. Eels’ comparatively complex lifecycle may be made possible by extra copies of key developmental genes.
• Yes, it’s real. No, we don’t know why. What science knows—and what it doesn’t—about the runner’s high.
• I don’t think I’d call any crocodilian snout “dainty,” though. The shapes of an alligators’ and crocodiles’ snouts don’t make a difference for the strength of their bites.
• Alas, it won’t produce flour ready-made for Girlscout cookies. Wheat engineered to carry and express genes from mint could repel aphids.
• As if you needed an excuse to build a robotic squirrel. The purpose of ground squirrels’ rattlesnake-repelling tail-waving, tested using a robotic squirrel.
• Because, as we all know, humans stopped experiencing natural selection 20,000 years ago. Is it possible that human speech and music are purely products of cultural evolution, instead of natural selection?
• Less obviously, that is. Fruit flies left to evolve in complete darkness for 1,400 generations change less than you might think.

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