- Assume a male sparrow (species X) is hatched and reared in isolation and allowed a critical imprinting period to hear the song of male of another sparrow (species Y). Now after the isolation, what kind of behavior wills species X show?
(1) It will sing the song of species Y that it had heard in the critical period
(2) It will sing the song of its own species X
(3) It will not sing at all
(4) It will sing a song not sung by either X or YWhat Is Imprinting in Songbirds?
Imprinting is a form of rapid learning that occurs in a specific, sensitive period early in life. For songbirds, this critical period is when the young bird is most receptive to learning the song patterns it hears. The song learned during this time becomes the template for the bird’s adult vocalizations.
The Experiment: Cross-Species Song Exposure
Let’s consider the scenario:
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A male sparrow (species X) is hatched and reared in isolation, with no exposure to its own species’ song.
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During its critical imprinting period, it is exposed only to the song of a male from another sparrow species (species Y).
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After this period, the bird is removed from isolation.
What Song Will the Sparrow Sing?
The answer lies in decades of research on song learning in sparrows and other songbirds. Studies have shown that:
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If a young male sparrow is exposed only to the song of another species during its critical period, it will imprint on that song.
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When it matures, the sparrow will sing the song it heard during imprinting, even if it is not the song of its own species.
This demonstrates that song learning in sparrows is not purely instinctive but depends heavily on early auditory experience.
Why Does This Happen?
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Critical Period: There is a window early in life when the bird’s brain is especially sensitive to song patterns. Exposure during this period determines the song template.
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Lack of Own Species’ Song: If the bird never hears its own species’ song, it cannot develop the correct song pattern and will instead mimic what it heard.
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Behavioral Flexibility: This learning mechanism allows birds to adapt to their local environment, but also means that unusual experiences (like being exposed only to another species’ song) can override innate tendencies.
What If the Bird Is Not Exposed to Any Song?
If a sparrow is reared in complete acoustic isolation, it may produce abnormal or incomplete songs, often referred to as “isolate songs,” which are not typical of either its own or any other species.
Summary Table
Scenario Outcome Exposed to own species’ song during critical period Sings own species’ song Exposed only to another species’ song Sings the other species’ song No exposure to any song Sings abnormal or incomplete song Conclusion
In the described scenario, the male sparrow (species X) will sing the song of species Y that it heard during its critical imprinting period. This outcome highlights the powerful role of early experience and imprinting in shaping song learning in birds.
Correct answer: (1) It will sing the song of species Y that it had heard in the critical period
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