Glossophaga longirostris: Some have very short nose leaves. Others have nose leaves as long as their ears.

Phyllostomus hastatus: In addition to the noseleaf, there is a horseshoe beneath the nostrils, and on the chin there are various kinds of ornaments. Nobody knows the significance of these ornaments and barely what the function of the noseleaf is. We think it serves to direct returning ultrasound echoes into the ears so that the bat gets a better fix on the direction of a target it has located.

(Phyllostomus elongatus): You see a bigger, more prominent horseshoe, longer spear-like noseleaf, and a more elaborate chin ornament. There's not a suggestion even as to what the chin ornament is for. Maybe when nuzzling other bats it's like Braille. The bat can know whether to fly away or to snuggle up, depending on the Braille on the other bat's chin. You notice inside the base of all of the ears there's a protuberance. That's a tragus. You've got a tragus on the bottom of your ear, too, but it is not so prominent. The function of the tragus is not very clear either. It must have something to do with returning ultrasound signals. There's a lot of ground out there for anatomists and behaviorists to cover with bats. There's more we don't know about them at this point than what we do know.