These are true flight feathers as seen in modern birds.
This behavior, which may have helped to keep the head warm, is also characteristic of modern birds.
Many modern birds are highly social, often found living in flocks.
This is a key function for the flight stroke of modern birds.
Advanced as the Confucius bird seems, its kind did not lead to modern birds.
It is a relative of such modern birds as ostriches.
Bambiraptor had a brain size in the lower range of modern birds.
This is almost identical to the way modern birds sleep with their heads under a wing.
Its feathers are almost identical structurally to those of modern birds.
They are not part of the clade which resulted in modern birds.