Give it more attention or remove it from the environment that is causing it stress. There is a medicine or treatment available from a Vet. that may help it stop. I'm not sure of the name, something like Pluck no more but any Vet. that treats birds should know what it is. It may be as simple as making more time for the bird. I have 7 and it can be demanding at times giving them as much attention as they want.
There are a few causes for this. This bird may have a genetic disorder in which feathers do not grow. OR this bird could be a plucker. This means the bird plucks it's feathers. Either way, you are going to want to take it to an AVAIN vet to get it checked out.
how the feathers protect the bird
As far as we know, there is no bird living without feathers.
how the feathers protect the bird
It will not be able to fly with no feathers. Feathers keep a bird warm. If its feathers are gone it will die of cold. Most importantly feathers help a bird to escape from predators.
Another name for bird feathers is down.
Down feathers are feathers that lie under a birds body and primary feathers. These feathers are small and puffy, and trap warm air under a bird's feathers.
Feathers that are on the neck of a bird.
Bird bones because feathers are very light and the bones just depend on the type of bird.
we are asking is there not a baby bird with yellow veins in its feathers
A vulture doesn't and I think a Condor also.
if it has feathers