We're well into autumn here in England, but there should still be a few bats about to add some romance to Halloween, even if they're made of rubber.
Bats are so incredible that I'd need a whole book to list all their wonders, but did you know:
That some bats scream four hundred times a second and use the echoes of the screaming to stop themselves bumping into things in the dark?
That a bat the size of a mouse can make a noise as loud as an express train (though the sound is so high that humans, luckily, can't hear it)?
That the bat can't hear it either, because to stop itself deafening itself it dislocates its ear drums four hundred times a second, too -and then reconnects them in time to hear the echoes of its screams.
That there are other bats which emit one long constant scream, and their way of avoiding making themselves deaf is to scream at a particular pitch they can't hear, and then rely on the Doppler effect* to change the pitch of the echo so they can hear it.
As I say, I could go on forever, but I'll leave you with something sweet:
Spot the frippet: bat. In the 14th century this word was bakke. It probably comes from Scandinavia, as there's a lovely Old Norse word ledhrblaka, leather-flapper, and a Swedish dialect word natt-batta, night bat.
*The Doppler effect is what's going on when you hear the pitch of a siren or an engine change when it switches from travelling towards you to travelling away fom you.