Question

Which event indicates that evolution has occurred?
Responses

Squirrels store acorns and other nuts in holes to have food over winter.
Squirrels store acorns and other nuts in holes to have food over winter.

Most acorns that an oak tree drops each year are eaten by animals.
Most acorns that an oak tree drops each year are eaten by animals.

The number of robins with an allele for bright red chest feathers increases.
The number of robins with an allele for bright red chest feathers increases.

The allele frequency for long tails in green anole lizards is constant.

Answer 1

The event that indicates that evolution has occurred is:

**The number of robins with an allele for bright red chest feathers increases.**

This statement reflects a change in allele frequency within a population over time, which is a key indicator of evolutionary processes occurring. Evolution involves changes in the genetic composition of populations over generations, often driven by factors such as natural selection, genetic drift, or gene flow. The increase in a specific allele in the population suggests a change that can be tied to evolutionary mechanisms.