It is eye-opening to discover from ethologists that the general blueprint for the development of social behavior is the same in all vertebrates. All vertebrates means all fish, amphibians, reptiles, birds, and mammals. Yet in all these myriad animals — ourselves being included — the same behavior pattern appears without being learned. The very young are watched over either by one or both parents (an early protective behavior which obviously has high survival value); then during the middle stage of development, the young leave the nest, or family, and go about together in packs of young males and females. It is a time for exploring and adventuring. Eventually, as adulthood approaches, the females begin to split off from their youthful groups, and so do the males from their gangs. The males go off by themselves to begin establishing nests or territories of their own, defending the areas from encroachment by others of their species and usually engaging in some kind of prenuptial preparations. As the males encounter individual females, a specific courtship ceremony occurs that, if successful, leads to a mating of the two, the procreation of young, and the protection of the young until they abandon the nest for their packs and continue through the same cycle. This is the kind of blueprint for behavior which ethologists find operating in all animals, whether they are describing the most general features of phyla, classes, and orders of animals or whether they are pointing out the specific blueprint of behavior ingrained in particular species.
What is quite enlightening is that at the most general level of behavioral description, ethologists see all animals as being motivated by four basic adaptive drives, each of which is very practical: flight, aggression, nutrition, and mating — or, if you prefer a subjective listing: fear, anger, hunger, and lust. All animals display these major "big four" drives — as Lorenz terms them-a-nd each species displays each of these drives in very particular ways, according to its phylogenetic blueprint.
An animal flees from a threat if it is too formidable to repel. An animal aggresses against a threat if he is capable of repelling it. Also, an animal will show specific ways of seeking and hunting for nutrition and equally specific ways of courtship and mating.
Even more intriguing are the ways in which the mutations of evolutionary history have brought about neurophysiological coordinations between these "big four" drives. The male in certain fish, upon achieving young adulthood, establishes his nutritional territory, works within it, and defends it. If another male of his species (remember that members of the same species are competitors for the same food and mates) happens to swim into his territory, the resident male flushes, flares out his fins like the Spanish Armada, and attacks. The intruding male, in the face of this aggressive behavior, pales, tucks fins beneath his belly, and flees — and he flees right back to his own centrum. But once he reaches his nesting territory, a dramatic change automatically takes place. Suddenly, he stops, and the pale, beaten look fades as he turns to face his pursuer: his fins become stiffly erect, his color darkens, and he is the one who now becomes puffed up with power and rage as he rushes at the intruder in his own territory. And — you guessed it — the pursuer, now faced with a totally different situation, shows the typical signs of flight behavior and palely flees back toward his own home territory.
It is in this way that the territorial males manage to live as separate neighbors, spreading out in spaced sections throughout the nutritional biotope, so that there is a balanced amount of nutrition for all members of that species. In this simple illustration we have seen how drives of nutrition, aggression, and flight all operate phylogenetically not only to guarantee the survival of each individual, but also to create an optimal social distribution so that the whole species may survive.
The way in which the mating drive may correlate with the other three drives is also an intriguing affair. The bachelor male, let us say, is minding his own business, swimming about his own territory, and feeding. Suddenly, another member of his own species, a competitor, intrudes within his realm. Automatically, the fins come out strongly, the flesh swells and colors, and he charges toward the intruding fish. However, there is a difference: In this case, the intruding cospecific is not a male, but a female. A cospecific intruder she is, and so charge he must to defend his feeding area. However, something arresting takes place: even though he begins his charge directly at the female intruder, he misses her. Somehow or other, he just doesn't manage to ram into her. Instead, he charges, then slips to one side, and engages in a series of vigorous, furious, zigzag movements which push mighty waves of water toward the intruder.
The female, for her part, is apparently frightened, and automatically shows signs of flight behavior when the male charges. She turns to fleebut not very far. Lingering a bit, as if overwhelmed before the ferocious charge, she observes as the male energetically zigzags to show how powerful and invincible a defender of the nest he can be; and the female, fleeing but not quite escaping, seems hesitant and awed, as if saying, "Oh my, what a big, strong brute you are!"
In his ambiguous behavior, the male has demonstrated how the practical imperative of defensive aggression has become allied with the practical imperative of mating to produce a unique form of courtship behavior. The female has shown how the automatic triggering of flight behavior has become phylogenetically intertwined with the mating drive, producing in her a type of coy behavior.
Examples of these phylogenetic blueprintings of behavior are as many and varied as are the many and varied species of animals existing on this planet. Such behavior is delightful and instructive to us because the animal we know as man has always enjoyed and profited from the similarity-despite-difference which he finds in other species of animals. Our common evolutionary pilgrimage and our common, primeval origin from simple life forms relate us to the entire kingdom of animal life as equal members of an old and familiar family.
I mention these things about ethology, not only because it represents a crucial and revelatory extension of biology but also because it allows us to fill in some specifics about the two modes of survival and adaptation, namely, assimilation and accommodation.
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