Question

Birds are adaptive to aerial mode of life :which of the statement is not correct ?
1 fore limbs are modified into wings for flying
2 feathers present on the body provide insulation
3 lungs shows air sacs attached to it
4 heavy bones are present to reduce to weight of the body and help in flying

Answer 1

it might be 4th option.......because they don't have heavy bones.for flying they require light weight and hence heavy bones have got transformed.