The visible part of the outer
ear, which serves to collect sound and funnel it into the external auditory
meatus (ear canal). Also known as the auricle
(which see for more anatomical details), it is present in some mammals,
including humans, and is made of cartilage.
In some species, such as cats and dogs, the pinna is movable and helps locate
the direction from which sounds are coming.
|The long-eared bat has large, elaborate pinnae that
play a crucial role in its sonar system