The Galapagos cormorant is a flightless seabird
Compared to other cormorants, which can fly,
it has short wings and a reduced chest
There aren’t many land predators in the
isolated Galapagos Islands.
Cormorants don’t need to fly away from threats,
so selection has removed the need
for big wings and breastbones.
But how does evolution make these changes?
Researchers sequenced the
Galapagos cormorant's genome
to find out how its flightlessness evolved
They found changes in the function of hair-like
cellular structures called cilia.
One gene in particular
involved in regulating cilia
was missing a small piece
found in all other birds and mammals
Cilia on cells called chondrocytes pass on
important signals during development.
These signals are needed for
bones to fully mature
in both birds and humans
This function appears to be delayed in the
cilia of Galapagos cormorants
Similar mutations cause diseases in humans
called ciliopathies,
which can be linked with shorter
arms and reduced chests
This research suggests a route for 
flightlessness to evolve rapidly
And for these birds to become the
ideal island-dwelling swimmers
