Question

Assertion: All birds except the ones like Koel (Cuckoo), build nests for retiring and taking rest during night time (day time for nocturnal birds)
Reason: Koel lays its eggs in the nests of Tailor Bird

A) Both assertion and reason are correct and the reason is the correct explanation for the assertion.
B) Both assertion and reason are correct but the reason is not the correct explanation for the assertion.
C) The assertion is correct but the reason is incorrect.
D) Both assertion and reason are incorrect.

Answer 1

Hint:Koels are genus of cucooks from Asia,Australia and Pacific.They are large sexually dimorphic cuckoos that eat fruits and insects and have loud distinctive calls.

Complete answer:
All birds, except the ones like Koel (Cuckoo), build nests for retiring and taking rest during night time(daytime for nocturnal) because cuckoos are brood parasites that do not make their own nests.And they lay their eggs in the nest of crows and not in the nest of tailorbird. Koel (Eudynamys) lays eggs in crow's nest for incubation and rearing of their young ones and not tailor birds. Koel and cuckoo need not build nests because they transfer their responsibilities to build nests, incubate eggs and nurture hatchlings to other birds especially crows. Thus they are called "brood parasites". Being the brood parasite of the crow, the koel’s breeding cycle synchronizes with that of the crow. Both the koel’s and crow’s eggs are grey-green with rusty brown markings. The tailorbird is a garden bird that makes its nest by sewing, it has no direct relation with koel and cuckoo. Being the brood parasite of the crow, the koel's breeding cycle synchronizes with that of the crow. The tailorbird is a garden bird that makes its nest by sewing, it has no direct relation with koel and cuckoo.

Thus,option ‘C’ is the correct answer.

Notes: The eggs of crow and koel are grey-green colour with rusty brown markings on it.Tailor bird is known as garden bird.It builds its nest by sewing.