22.3 evidence

Question 1

common ancestry resulting from structural similarities

Answer 1

homology

Question 2

variations on a structural theme that was present in the common ancestor:

Answer 2

homologous structures

Question 3

remnants of features that served important functions in the organisms ancestors:

Answer 3

vestigial structures

Question 4

the biographical distribution of species

Answer 4

biogeography

Question 5

species found nowhere else in the world:

Answer 5

endemic species