Environmental challenges and predation pressure

By Per Inge Oestmoen

The precise mental and physical qualities that are selected for in living beings are to an overwhelming extent determined by the presence of different environmental pressures, and to the added characteristics of these challenging factors.

If we are talking about what influences the presence of natural predators exert on other animals in the ecosystem and on their prey in particular, it will be apparent that the qualities selected for are those necessary for overcoming and surviving the challenges presented by the predators. Each environmental challenge will always have its own subtle or not so subtle influence on the organisms. In our context, each predator species will have its own particular predation tactics and patterns. Hence it will help in the selection of powerful abilities and survival strategies in its prey, in accordance with these patterns.

The term for this mechanism is predation pressure.

Some quotations from the wolf researcher L. David Mech will illustrate how it works. Mech writes this in his book "The Wolf," on page 266:

"Any environmental forces that affect the survival of a living thing would influence the development of the species to which it belongs. Because the wolf and its ancestors have long exerted such a direct effect on the survival of great numbers of prey, there can be no doubt that wolf predation has helped modify several prey species. Probably those traits most closely related to detection of danger, to defense, and to escape would be most affected. It is obvious that if a genetic strain of caribou were to arise that has superior leg musculature, for instance, individuals with this trait would tend to survive longer and produce more offspring. No doubt the same is true for a strain that possesses superior senses. One would expect then that in most species of the wolf's prey increased alertness and running speed would be a direct result of millions of years of wolf predation. The defense formation of musk-oxen, the size and strength of bison and moose, the fleetness of deer, and the nimbleness and agility of mountain sheep probably developed in this way."

On page 267 in the same book he continues:

"An interesting contrast that might show the effects of the wolf on the defensive traits of its prey species is the comparison between the ease with which domestic animals are killed and the difficulty with which wild creatures are captured (Chapter VIII and IX). It is reasonable to suggest that the difference results from the lack of predation pressure on domestic species, pressure that has ensured the persistence of traits such as alertness and fleetness in the animals."

These were the words of L. David Mech.

The point is that wolf predation serves to maintain strong qualities in the prey animals, qualities that would not be maintained in the long evolutionary perspective were such predation pressure to be absent. The sharp senses, the instincts for sophisticated orientation in a complex environment, effective strategies for evasion, escape and counterattack, all the highly developed mental and bodily abilities essential to functioning at this level, are very much a result of an environmental challenge in the form of continuous predation pressure from predators that live in the same environment.

At the same time the predator, here exemplified by the wolf, although the principle applies to all predator-prey interactions, requires similar abilities to counteract the defenses of its prey. Thus wolves have to evolve their own powerful senses, detection capabilities, strength and endurance in order to cope with their prey. Needless to say, this kind of interaction guarantees that both predator and prey will be endowed with qualities, abilities and possibilities they would otherwise not enjoy.

The net result is that both sides benefit tremendously from this reciprocal give-and-take which might superficially seem to be "brutal" or even "cruel." In reality the constant struggle is truly benevolent in its ultimate effects. The appreciation of this mechanism and its results is a crucial element in our development of ecological understanding and environmental ethics. This because it corresponds with our appreciation of natural values and wild conditions as opposed to an environment that has been cultivated, reduced and degraded by excessive human activity and dominance. To admire and value natural abilities in animals is to perceive the significance and beauty of Mother Nature's wild qualities.