Question

what are the two characteristics features present in the aves ??? why are the bones of birds so light

Answer 1

hii
your answer is
birds have light bones because the help them to fly easily
hope this helps

Answer 2

The two characteristic feature of birds are:
Forelimbs are modified into wings.
Jaws are modified to form beak.
The bones of birds are so light because they are pneumatic bones that contain air spaces.
This allow them to fly high in the sky