Chapter 29, Problem 26A

Summary Introduction

To hypothesize:

The larger a bird’s eyes are, the earlier in the day it sings.

Introduction:

The cacophony in the morning is mostly of males for impressing the potential mates and rivals. They warm up before the sun rises as low light makes it difficult to work or hunt for insects.

Explanation of Solution

The good sighted early birds get worms easily and earlier. Big eyes help in hunting for breakfast. Birds also use singing to attract mates and for defending their territory or for alerting predators.

Hence a bird doesn’t sing if it cannot see the approaching danger as they don’t waste time crooning when they can search food. The earlier they see, the earlier they sing and the earlier they start looking for food.

Conclusion

At dawn birds with large eyes begin singing earlier than the small-eyed because as they see in low light also.