Page 871 - Atlas of Creation Volume 1

The Design in Bird Feathers

n first examination, bird feathers don't appear to
contain that many features. When inspected
O more carefully, however, feathers— which are

light but strong and impermeable to water—are seen to
have a highly complex structure.
In order to be able to fly, birds must weigh as little as pos-
sible. In line with that requirement, feathers consist of ker-

atin proteins. On both sides of each shaft of the feather are
some 400 side branches, or barbs, each with approximately
800 tiny hooks, or barbules. On each of these 800 barbules
are 20 smaller hooked filaments, called barbicels, that hold

the parallel barbules together, like zippers connecting two
pieces of cloth. The total number of barbicels in all the
feathers on any one bird is approximately 700 billion.
The complex structure of barbs and hooks that lock a

feather together serves a most important function.
Feathers need to be closely bound together in order not to
become separated, frayed and useless when the bird flies.
Thanks to this mechanism, each feather is bound together

so closely that neither strong winds nor rain can break up
its continuous surface.
The down-feathers are not the same as those on the wings
and tail. The very large tail feathers serve as rudders and

brakes. Meanwhile, the wing feathers increase surface area
and thus, lift by opening up when the wing flaps down.