Owls

Order: Strigiformes - from latin strix meaning owl.

Owls are a well recognised group of birds that have a distinctive facial characteristics and eyes. Owls have large forward-facing eyes and ear-holes; a hawk-like beak; a flat face; and usually a conspicuous circle of feathers, a facial disc, around each eye. 

P7080120

Male and female Snowy owls (Bubo scandiacus). image: R.Conan-Davies

Most owls are nocturnal and hunt small mammals such as mice. They are also known for having specially adapted tips of their flight feathers that minimise sound making them almost silent when swooping in to catch prey.


Tyto_alba_-British_Wildlife_Centre,_Surrey,_England-8a_(1)

Barn owl (Tyto alba) with prominent characteristic face. image: Peter Trimming/ wikipedia


Owls are known for their disproportionally large eyes in comparison to their skulls. A consequence of the evolution of  large eyes in a relatively small skull is that the eyes of the owl have become tubular in shape. 

Bubo_virginianus_8zz

the skull of a Great Horned Owl shows the tube like eye socket. image:David J. Stang/wikimedia

Owls are able to rotate their heads some 270° this is because their eyeballs are unable to move (ocular immobility). These are all adaptations for hunting prey in dim light. 

vqzdRyK


Why do owls often have round faces?

The shape of their face and some of the feathers are able to concentrate sound waves and direct them to their ears allowing them to target tiny sounds made by their prey.  This feature is called a facial disk.


Further reading

http://en.wikipedia.org/wiki/Owl