3.
Humans, mice and giraffes share a common ancestor. What trait helps scientists understand that these organisms share a common ancestor?
They are all very different in size
They all have seven vertebrae in their necks
They once had wings
They are all bipedal
1.
Natural selection is:
the idea that traits that help animals survive and reproduce become more frequent.
embryos sharing features in the late stages of development.
that all vertebrates have seven vertebrae in their necks.
2 answers
They all share homologous structures such as the structure of the forelimb as seen in their anatomy.