Head of a pipistrelle bat. Coloured scanning electron micrograph (SEM) of the head of a pipistrelle bat (Pipistrellus pipistrellus). Bats are the only mammals in the world naturally capable of flight. About 70 per cent of bats are insectivorous and many are nocturnal. They are not blind, although many species do have small eyes and poor eyesight. Instead they have large ears for echolocation, in which they emit high-pitched sounds in regular patterns and using the returning echo to locate and identify objects. Magnification: x8 when printed 10 centimetres wide.