Interesting facts

I thought we could start a thread for sharing facts we love or find interesting/fun. Next time we're due to be in a social situation where it might be expected to share a fact as part of introducing ourselves, we can have this thread as a resource to look through so we have something ready. And at least as importantly I think, this can also be a space for info-dumping favourite facts about special interests. I'll start:

Parents
  • During mating, male cuttlefish disguise the upper half of their body to look like a female so that other male cuttlefish think it's two females socialising and don't interrupt.

Reply
  • During mating, male cuttlefish disguise the upper half of their body to look like a female so that other male cuttlefish think it's two females socialising and don't interrupt.

Children