Question

why are bird' calls not frequently heard in cities?​

Answer 1

Answer:

Scientists have discovered that birds in cities sing louder and higher in order to drown out the background noise of cars, building sites, and other sources of commotion. ... When they start singing at the crack of dawn, they can reach 90.95 decibels, about the same noise level as a jackhammer.

Explanation:

Answer 2

Answer:

This is my own answer I think that cutting down down of trees they don't have home to live

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