Field mice always sleep facing northwest. Kangaroos can't walk backwards. Female hyenas have penises. Let's face it, nature is weird. What's the strangest thing you know about the animal kingdom?
I don't know if this is The Strangest Thing I know about the animal kingdom, but I always thought it kind of neat that while honeybee workers and queens are diploid, honeybee drones are haploid.
NB: For those who may not be biologists, this essentially means that honeybee drones hatch from unfertilized eggs.