Correct option is D
The Asian Koel (Eudynamys scolopaceus) is a brood parasite, meaning it lays its eggs in the nests of other bird species, particularly crows and mynas, which raise the koel chicks as their own. Despite growing up among foster parents, Asian Koel chicks do not learn the calls of their foster species. Instead, their vocalizations are innate (genetically programmed) and develop naturally as they grow.
Key Evidence Supporting Innate Calls:
- Even when raised in isolation, Asian Koel chicks produce their species-specific calls.
- Despite being raised by crows or mynas, koels do not mimic their foster parents' calls.
- Koels have distinct loud, repetitive calls, particularly the "kooo-kooo" call of males during the breeding season.
Information Booster
Brood Parasitism in Asian Koels
- Koels lay their eggs in crow and myna nests to avoid parental investment.
- The chick hatches earlier than the host's chicks and competes for food aggressively.
- Unlike cuckoos, koel chicks do not kill host chicks but often outcompete them.
Koel Calls are Innate
- Calls are important for territory marking and mate attraction.
- Innate calls ensure that koels can recognize and communicate with their own species despite being raised by a different species.
Other Birds with Innate Vocalization:
- Doves and pigeons (cooing sounds).
- Owls and hawks (predatory calls).
- Unlike songbirds (passerines), which learn calls from parents, koel calls are genetically programmed.
Additional Information
Option (1) The brood of the bird is usually infested with parasitic wasps (Incorrect):
- Koel nests are not associated with parasitic wasps.
Option (2) The young ones learn the calls of their foster parents (Incorrect):
- Koel chicks do not mimic crow or myna calls. Their calls are innate.
Option (3) The bird feeds parasitic wasps to its brood (Incorrect):
- Koels are frugivores (fruit-eating birds) and do not feed insects to their chicks.
