Why are vestigial structures are considered examples of
homologous structures?

Vestigial structures are often homologous to structures that are functioning normally in other species. Therefore, vestigial structures can be considered the evidence for evolution, the process by which beneficial heritable traits arise in populations over an extended period of time.

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The hawk receives 0.1% energy from the caterpillar although the caterpillar gets eaten by another bird smaller than the hawk first