The variation is only the criteria that apply before selecting a beak in natural selection.
What do you mean by Natural selection?
Natural selection may be defined as the favorable variations that assist any organism to survive and reproduce in a particular habitat.
The Earth had formed about 4.6 billion years ago. About 3.5 billion years ago, the first prokaryotic cell was formed. While about 1.5 billion years ago, the first eukaryotic cell was formed.
Vestigial structures are those structures that most likely had a function at one time, but no longer serve as a known function.
Therefore, each of the questions are described above.
To learn more about Natural selection, refer to the link:
https://brainly.com/question/14385908
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