"....social life is not an accident which appears sporadi cally among a few highly developed animals. It is a nor mal and basically widespread phenomenon,"
W.C.Allee^
A theory must explain our observations, and a theory of ethics phrased in terms of the evolution of altruistic and cooperative tenden cies in group-dwelling or related animals would be idle if cooperation were never found and group-dwellers nowhere existed. The purpose of this chapter is to give examples of social cooperation in animals, and to emphasise the point (which contractarians such as Hobbes or Rousseau did not have the power to detect and which they would have found very damaging to their theories) that social life is found in a multitude of species whose rational powers are decidedly limited.
The ubiquity of animal social patterns is almost as great ‘as the diversity of their forms. Accordingly, animal social behaviour can be of interest to philosophers only if these manifold varieties of pattern can be presented as the various expressions of behaviour which, by and large, has the same functional importance in each species. It is the content of social behaviour which is under scrutiny here, and not the multiplicity of its forms. For the sake of simplicity, ‘ we will treat here a small number of particular characteristics prevalent 'dn animal
social life. In this chapter we will be concerned with aspects of
group organization, and in the following chapter we will consider traits of cooperation and self-sacrifice more usually associated with morality.
Traits to he considered
The study of the determinants of animal social life is a recent one, hut it has already filled libraries. Only the most superficial coverage of the subject is therefore possible here. In particular, we will be restricting our attention to the following determinants;
(a) The structure of animal social groups, including aspects of behav ior conducive to social'aggregation itself, systems of rank and domin ance within groups, and the importance of characteristics such as age and sex in the determination of social roles,
(b) The maintenance of the group, including cooperative defence, iso lation from other groups, and traits influencing dispersion of the members of the group.
(c) Altruistic behaviour, parenthood, sharing of knowledge and re sources. These factors will be discussed in the following chapter, while (a) and (b) will be discussed here.
The structure of social groups
(l); Widespread nature of social life
Social aggregation seems to be an advantageous state, even in 2
the simplest animals, W.G.Allee suggests that even protozoa, minute creatures with very little learning ability and apparently no facul ties for rational calculation, thrive best together.; In conglomer ations of a certain optimum size, they are able to survive the effects of toxic substances which would be fatal if administered in proportion ate quantity to each separate individual, Allee concluded that the survival advantage of many forms of social life made it "inherent in living organisms."
At the other end of the size scale, Darwin himself observed the strength of social bonds in cattle,A herd he found in Uraguay num bered many thousand, although they were clearly assembled in small
groups of between fifty and a hundred, as the herdsmen knew. One night, violent electric storms caused the cattle to bolt and panic, breaking up the small groups. Psyche would have had an easier task sorting the seeds than attempting to restore the associations. Yet within another day, the cattle had found their old groups and were back with their fellows. The forces binding such companies seem to be of considerable power.
Between and beyond these extremes there are thousands of social species. The colonies of microorganisms, of social insects; the schools of fish and flocks of birds ; the small social groups of mam mals, including representatives from the carnivores, the herbivores,
the primates, the ungulates, the land-borne and the water-borne. In each, a definite pattern of social life can be discerned, different for each species and even between varieties from each species, but nevertheless structured and regular; often highly cooperative and
quite unlike the 'state of nature' upon which the classical social con trac tari ans founded their ethical systems.
(2) Cohesive forces
In 1932 Solly Zuckerman proposed that the binding force of pri- 4
mate sociality is sexual attraction. In the cages of London Zoo, the males fought for possession of females, and there was to him no indi cation that the sexual stimulus was ever absent. Two centuries before, Hume had come to the same conclusion about human societies, that they
were founded in the biological necessity of family life. Since the
1950s, however, the explosive growth of field studies has required biologists to abandon this unifying theory of social organization. : Primates in the wild have sharply defined breeding seasons, and yet
they remain in social groups : as Jane Lancaster and Richard Lee re ported, "It:\is clear that constant sexual attraction cannot, be the basis for persistent social groupings of primates."^ The same obser vations would undoubtedly apply to many other social animals, and cer tainly to our own primate species.
What is it then, which makes species form their social aggrega tions? There is probably no single factor which will explain it-, A
great variety of behaviour seems to require the presence of other mem bers of the species, whether feeding, sexual behaviour or even sleep ing, The appetites for these and other behaviour need the stimulus of conspecifics for their satisfaction, it appears, in addition to the other stimuli. Social life is often secured by bonds_6f apparent aff ection between individuals. In many species, sexual pairing is for life, and in many more it is annual but very firm. Bonds between par ents and offspring may be broken only by death: although animal rela tionships are generally more limited in scope and duration than human ones, it is nevertheless common to find members of a social group re maining together in that group for their lifetimes. Hence it seems that social life is not only highly prevalent in animals, but that ani mal societies are often powerfully cohesive.
The advantages of social life are many, and it is no surprise that natural selection has favoured it so broadly. The possibility of de fence against predators is greatly enhanced by aggregation, as will be shown later in the chapter. Competition with other species for food or territory is made easier. The chance of finding new food sources is improved. Learning from successful individuals becomes a feasibility. Adapting the environment to suit species needs can be a reality. In creases in reproductive rates and early survival are also common out-
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comes of social life. So advantageous-is this*state, indeed, that se lection ihas apparently favoured mechanisms to prevent the emergence and spread of nonsocial tendencies; for instance the infant monkeys separ ated from all others by the Harlows had difficulty mating and neglected their own offspring.Participation within the social group was an im portant ingredient in personal fitness; were a nonsocial tendency to arise naturally in this species, it would be unlikely to survive a second generation.
(3) Dominance and social structure ■'
The backbone of many social organizations is the so-called domin ance, rank, or pecking order. The latter name was coined by Schjeld- erup-Ebbe to describe the phenomenon in domestic hens, although the concept is o l d e r . I f a number of hens are placed in an enclosure,
antagonism and fighting commonly occur. Gradually, however, the overt aggression decreases and each individual assumes a place in a 'pecking order* such that he is dominant over those below him and submissive to those above. Sometimes this means that an individual is able to peck others without retaliation, but in other animal societies the pecks go both way^ although predominantly in a single direction. The rigidity of the order also varies in different species and circumstances.
The dominance concept has been useful in the study of many animal
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societies, from social insects up to the higher primates. While ir regularly distributed among species, dominance is found mostly.among vertebrates and some invertebrates of large size, possibly because the degree of memory required to sustain any dominance relationship is to be found only in the more highly evolved forms.
Although sometimes linear, dominance orders are prevalently rather complex. Altman has noted from his field observations that rhesus mon keys engage in what Lionel Tiger calls "quasi-political coalitions and pacts" within the dominance order, and it is known that challenges to a dominant individual are frequently made by such concerted efforts by
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