The oldest populations in Latin America and the Caribbean are in Puerto Rico and Martinique.
To me it looks like the answer is a because i dont remember him using that as evidence for his theory from bioligy<span />
San Andreas fault is a transform fault- it means that the two plates are not getting closer and converging or getting away from each other and diverging but rather moving in different directions - the American part is moving South and the Pacific part is moving North.