Echolocation in Bats

I've been fascinated by bats and how they navigate ever since I read Richard Dawkins' book (The Blind Watchmaker—I think it was that one), where he tries (and fails) to explain echolocation in terms of evolution (laughable if you ask me). At any rate, researchers have produced evidence that when bats fly in packs they "turn off" echolocation for long amounts of time (bat time that is) so their signals don't get confused.