beats me!
my best estimation is that when conditions are perferct whales will achieve there full maturity. a time line is unsatisfactory due to global change and conditions. maybe the time and place is just right for whales to prosper or maybe they have more to say about our earth. i think they are a creature that requires a broader study. it seems to me the only thing that has hurt this mammal is human intent such as military testing of sonar or other such radars. it's of interest to me how an aquatic creature such as a whale and a land deweling animal like an elephant are the biggest receptors of sound in water and on land, which i might add are or have been hunted for human prosperity, both of which creatures hear more of the earths activities then no other.
the farming of cattle is a bit easier then the farming of whales but the practices of being a vegetarian are proven to be the best.