[waves crashing, birds screeching]
- The flightless cormorant is a beautiful example
of rapid evolution in a sort of negative direction.
Other cormorants fly,
and they have trouble keeping their wings dry afterwards.
They have to hang their wings out to dry.
The Galapagos flightless cormorant
has reduced its wings.
It can no longer can fly,
but it still goes through the motions of drying its wings,
which is sort of bizarre, in a way.
Quite often, we see in evolution
that animals will lose something.
because they don’t use it.
And you might think,
“well, why not just keep it anyway?”
But the answer is that it costs energy.
It costs food to make something like a wing,
and so it does make sense to lose it.
So you might think,
“well, maybe they would like to fly once in a while.”
But it isn't worth it.
It’s better to save the economics of making a wing,
and they have very, very powerful feet
with which they swim.
I’ve actually dived, snorkeled,
with a flightless cormorant.
It’s a magnificent sight to see.
This phenomenon of losing things,
like losing wings in the Galapagos cormorant,
it’s called a vestigial organ.
And Darwin himself made great use of vestigial organs
as evidence for evolution,
because it would be very hard for a creationist
to explain why the Galapagos cormorant
has these little, tiny wings that are no use for flying.
But of course, on Darwin’s evolution theory,
it’s very easy to explain.
The ancestors had wings, and gradually lost them.
Vestigial organs,
one of Darwin’s key arguments.