+3 votes
in Class 12 by kratos

Assertion: All birds, except the ones like koel (cuckoo) build nests for retiring and taking rest during night time (day time for nocturnal).

Reason: Koel lays its eggs in the nests of tailor bird.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not correct explanation of A

(c) A is true but R is false

(d) A and R are false

1 Answer

+2 votes
by kratos
 
Best answer

The correct option is: (c)

Explanation:

Koels (cuckoos) need not build nests because they transfer their responsibilities to build nests, incubate eggs and nurture hatchlings to other birds specially crows. Thus they are called as "brood parasites". Being the brood parasite of the crow, the koel' breeding cycle synchronises with that of crow. Both the koel' and crow'* eggs are grey-green with rusty brown markings. Tailor bird is a garden bird which makes its nest by sewing, it has no direct relation with koel and cuckoo.

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