Octopus have weird bodies

Like lots of sea animals, octopus have blue blood! This is because it's based on copper, instead of iron like ours. Octopus are famous for being super intelligent, about as smart as a 7 year old human. They're smart in a very different way to us though - they even have 9 brains! They've got a brain in each leg, and a doughnut shaped one in the head. Imagine how they must think? Spoiler - you can't!