Question

THe pricky pear cactus became ususually abundant after its introduction in Australia, because it
A. had no coevolved hebivores
B. formed new mycorrhizal association
C. lost its thorns
D. all of these

Answer 1

Correct Answer - A
Coevolution is caused by the selection pressures that each of the two species exerts on the other. Since there has been no coevolved herbivore with prickly pear cactus, it became abundant in Australia.