Whether they’re opening for takeoff, spreading wide for a lazy soar or flapping to brake for landing, bird wings make flying ...

But a bird wing is vastly more sophisticated than anything composed of sheet metal and rivets. From a central feather shaft extends ... long tails—hardly the anatomy one would expect on a ...

Alteration of the expression of the co-called 'Sonic Hedgehog' gene can transform feet scale and wing feathers. While a transient over-expression of the gene can permanently turn feet scales into ...