Reader Mary sent me a video by the incomparable ZeFrank, and it’s a lovely one, a full 15 minutes about crabs with lots of great video and accurate biology. Mary said this:
Really good one with lots of interesting evolutionary implications!
There’s all kind of cool stuff about coconut crabs, the famous migrating red crabs of Christmas Island, hermit crabs, sponge crabs, decorator crabs, boxer crabs (don’t miss these!), spider crabs, fiddler crabs And yes, there’s evolution: straight adaptation in morphology and behavior by natural selection, sexual selection, and evolutionary tradeoffs.
(There’s an ad from 2:45 until 3:35.)