2. The pinnae are ears. In most mammals, the visible ear is a flap of tissue that is also called the pinna and is the first of many steps in hearing. In people, the pinna is often called the auricle. so obviously human have a pair of pinna.
The pinna notch is the range of audio frequencies that are suppressed due to phase-delay interference between sound that is reflected from the pinna (outer ear) and sound that travels directly to the tympanic membrane (eardrum). the largely cartilaginous projecting portion of the external ear
Humans have large ears that stick out (the sticking out part is called the pinna.) Frogs have small disk-hole things on the sides of their heads. Another difference is frogs only have one bone in their ear.
The outer ear consists of the "pinna" and the "external auditory meatus." The "tympanic membrane" is the border of the "middle ear." Notice that the diagram incorrectly labels the "pinna" as the outer ear. [The diagram is posted online without either a source or a copyright notice.]