> Under conditions which come close to being paradise—that is, no environmental hazards, unlimited food supply, and no detrimental interaction between elements—the fate of a biological population as a whole is completely determined at all times by reference to the two fundamental properties of an individual element: its fertility and its mortality.

(Emphasis mine)

The unreality of frictionless perfectly spherical cows strikes again...

Also, check out that lovely vintage emdash use!