Ask A Scientist Zoology Archive

 
name         Anay G.
status       student
age          13

Question -   How are owls able to turn their head all the way around
when looking for prey?
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Anay,

Owls have only one occipital articulation with the cervical vertebrae.   (That means 
there is only one bone situated on top of the backbone.)  Humans have two articulations.  
This allows the owl to pivot on the vertebrae column much like your body can pivot on 
one foot.  Their muscle structure is arranged in a manner that allows this movement as 
well.

Humans are pivoting much like using two feet to pivot.  It is much more limited.

Steve Sample
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Up-dated July 2008
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In addition to the special occipital structure, owls have twice the number of neck 
bones that humans (and many birds) do.

The third adaptation that owls have is a special arrangement of the jugular veins 
with associated bypass connector blood vessels, to ensure that blood supply (and 
return) are not impeded as the neck is rotated.*

Most birds need a fairly flexible neck for preening reasons, but owls have an 
additional motivation. They cannot move their eyes in their eye sockets to any 
meaningful degree, and they don't seem to have the multiple fovea that some birds 
(e.g., Terns) do, therefore to "look around" it's critical to have a flexible neck.

* Owls of the World, Dr. J. Duncan

Paul Bridges
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