Messages broadcast by sperm whales seem to come with a speaker's signature. At least that's how it looks based on a new scientific paper about sperm whale sounds. Could it be true that whales use names?
It makes sense, if you're a sperm whale listening to whale chit-chat, you want to know who's talking when you hear a juicy bit of gossip. Hey, guess who was out fooling around last night...?? Oh yeah, says who??
Here's an example of a sperm whale sound, and here's a place where you can click and listen to an entire collection of sounds from sperm whales.