Here’s a pectinate claw on an adult female in my study:
Nighthawk researchers have wondered whether this was a vestigial structure, an ancestral appendage that is no longer useful. This is because nighthawks have short, stumpy legs. They are clumsy walkers and are unable to perch in trees and instead lay on and parallel to limbs when roosting in trees. So, are nighthawk pectinate claws useful when presumably they cannot reach their short legs to their plumage?
Presume no more! They can and do reach their head with their feet while grooming.Having a hard time seeing the foot? Here it is.