548 THE STRUCTURE OF EVOLUTIONARY THEORY
The need for restraint in the midst of plenty, as it turns out, must apply to
all animals whose numbers are ultimately limited by food whether they are
predators in the ordinary sense of the word or not... Where we can still find
nature undisturbed by human interference, whether under some stable
climax of vegetation or proceeding through a natural succession, there is
generally no indication whatever that the habitat is run down or
destructively overtaxed. On the contrary the whole trend of ecological
evolution seems to be in the very opposite direction, leading towards the
highest state of productivity that can possibly be built up within the
limitations set by the inorganic environment. Judging by appearances,
chronic over-exploitation and mass poverty intrude themselves on a
mutually-balanced and thriving natural world only as a kind of adventitious
disease, almost certain to be swiftly suppressed by natural selection. It is
easy to appreciate that if each species maintains an optimum population-
density on its own account, not only will it be providing the most favorable
conditions for its own survival, but it will automatically offer the best
possible living to species higher up the chain that depend on it in turn for
food. Such prima facie argument leads to the conclusion that it must be
highly advantageous to survival, and thus strongly favored by selection, for
animal species (1) to control their own population-densities, and (2) to keep
them as near as possible to the optimum level for each habitat they occupy
(1962, pp. 8-9).
In Darwinism, this regulation proceeds by a fundamentally Malthusian
method—imposed from outside by a hecatomb on populations that outstrip
resources. Wynne-Edwards holds that such an indirect and inefficient mode of
external imposition wreaks havoc upon ecosystems, and that existing stabilities
therefore imply the operation of an entirely different system for regulating
populations—internally, by complex sets of behaviors that limit reproduction and
match population sizes to appropriate resources. Since the Darwinian imperative
leads organisms to maximize their own reproductive success, such internal
limitation can only be achieved by mechanisms of group selection powerful
enough to counteract the personal gains of individual organisms from conventional
Darwinian selection.
The ingenuity of Wynne-Edwards's theory lies largely in the range of
behavioral phenomena that he interprets as devices evolved by group selection for
limitation of population size. In fact, Wynne-Edwards ascribes the origin of social
organization itself to this need for limitation upon the size of populations. Note that
by "conventional competition" he does not mean the vernacular "orthodox" or
"ordinary" (which would then become Darwinian, or the opposite of his personal
intention), but rather apparent competition by bluff, ritual and display—convention
in this sense—rather than actual (and potentially destructive) fighting:
Undisguised contest for food inevitably leads in the end to overexploitation,
so that a conventional goal for competition has to be evolved in its stead;
and it is precisely in this—surprising though it may appear at first sight—
that social organization and the primitive seeds of all social