Child: “Mummy, why do people have to kill chickens?”
Mummy: “Because you can’t eat them if they’re alive.”

Correct answer.

BBC: Oldest hamster food store found
A hoard of nuts buried by a rodent 17 million years ago is the oldest food larder so far discovered in the fossil record, say scientists in Germany.

Apparently, the nuts were found near an ancient wire treadmill.