That feeling when you think you've figured out how the world works and then you find out that humans are striped like tigers and bioluminescent.
@dave oh yes we are. It's OK, my world is falling apart too.
@mister_monster I mean, we're really not though. Every piece of matter emits light that depends on temperature, so as a consequence all animals emit light. But it's not accurate to say any of them are bioluminescent unless they have their own separate process for generating additional light that can be detected by other members of their species.
I can make you some wicked zebra stripes with some sunscreen and a UV camera, though. 
@mister_monster we're not though?