They must be devolving into dinosaurs (no, not really)! Great tits normally live on a diet of seeds and insects, but when those resources are scarce, they’ll fly into caves and kill and eat bats. They don’t do it unless they’re really hungry — they prefer bugs and bacon, as do we all — so the interesting thing about is that these birds can push the boundary of what is expected of their species.

Follow the link, it has a short movie of a tit picking up a bat carcass and flying off to a branch to tear at it. Appetizing!