“It’s the same old tune, but the pitch of the blues is mysteriously lower – especially off the coast of California where, local researchers say, the whales’ voices have dropped by more than half an octave since the 1960s. No one knows why. But one conjecture is that more baritone whales indicate healthier populations: The whales may be less shrill because they’re less scarce and don’t have to pipe up to be heard by neighbors.”