R. A. Fisher on group selection in humans

Fisher, who's been called "the most important geneticist of the 20th century", like Hamilton saw a significant role for group selection in human evolution.

A.W.F. Edwards once confusedly mentioned "a passage new to the 1958 edition, where Fisher stresses the theme of the book, that it is individual, not group, selection that drives evolution", but the passage in question says nothing of the kind. The short section added to the 1958 edition of The genetical theory of natural selection is headed "'The benefit of the species'". In it, Fisher clearly acknowledges multiple levels of selection, and explicitly includes "co-operative communities" along with individuals as units of selection. Fisher is plainly responding to "good of the species" arguments, and merely points out that selection at the level of species or higher must, for empirical reasons, be relatively unimportant compared to selection on individuals:

There would, however, be some warrant on historical grounds for saying that the term Natural Selection should include not only the selective survival of individuals of the same species, but of mutually competing species of the same genus or family. The relative unimportance of this as an evolutionary factor would seem to follow decisively from the small number of closely related species which in fact do come into competition, as compared to the number of individuals in the same species; and from the vastly greater duration of the species compared to the individual. Any characters ascribed to interspecific selection should of course characterize, not species, but whole genera or families, and it may be doubted if it would be possible to point to any such character, with the possible exception, as suggested in Chapter VI, of sexuality itself, which could be interpreted as evolved for the specific rather than for the individual advantage. [p. 50]
Fisher obviously includes humans among those capable of forming "co-operative communities", as is clear from discussion elsewhere in the book:
The only animal societies in which co-operation is sufficiently highly developed to justify comparison with civilized men are those of the social insects.

Fisher has an entire chapter on social selection in humans, unaltered in the 1958 edition, in which he speculates about selection for traits like heroism in a landscape of intertribal competition, Fisher's conception of early human society being not unlike those of W. D. Hamilton and James Neel.

Note that while in this chapter Fisher emphasizes intratribal social selection favoring the kindreds of heroes, this sort of selection only makes sense in the context of intergroup competition; and in contrasting "selection on whole groups" -- which Fisher does not dismiss but which he notes will tend to be slow -- and selection on kindreds, Fisher is not at odds with people like Hamilton or Neel, who envision tribes expanding, fissioning along lines of kinship, absorbing other tribes, etc. The latter situation -- as opposed to one in which only unmixing platonic groups compete -- is exactly the one we would most expect to favor generalized adaptations for kin recognition and ethnocentrism, which in the modern world might quite adaptively be deployed in the context of interracial conflict (regardless of how difficult Cochran finds it to think generally about the issue).

It is necessary to emphasize this unity of culture because, unlike civilized societies having comparable unity, barbarian peoples recognize private, or more properly tribal war as a normal means for avenging and checking crime. The obligation to avenge a kinsman was felt extremely keenly as a moral duty, to shirk which would be incompatible with self-respect or an easy conscience, or, in Wilfred Blunt 's forcible phrase as 'almost a physical necessity'. The existence of this obligation requires that the tribes of kinsmen to which it applies shall be somewhat sharply defined, and with this obligation follows, of course, the obligation to pay, and the right to share, blood money, or to share in booty. A certain degree of economic communism thus characterizes these kindred groups, so that there is little exaggeration in saying that the economic and the military units in such societies are made to coincide. This is at least a convenient form in which to express the contrast with all civilized societies, in which the interests of the economic unit, consisting of a single individual and his dependents, may differ widely from those of the military unit, consisting of the entire nation to which he belongs. The interests of the kindred group as a whole, whose rights to life and property can only be safeguarded by military preparedness, are of course, in the first degree, founded upon military strength, and consequently, among other qualities, upon the fertility of its members.

Social position in barbarian societies consists partly in differences in kind, partly in differences in degree. A powerful group comprises not only the body of free tribesmen of authentic, or noble, pedigree, but also dependent freemen harboured by the tribe, who may have been outlawed from their own tribes, or be the remnants of tribes too weak to stand by themselves ; further there may be unfree depen- dents, whose position only differs from that of the slaves of civilized societies, in lacking the protection of civil law, and, on the other hand, in differing but little from their masters in education or standard of living. It is important here that differences in social standing are at least as strongly felt among barbarian peoples, as in civilization, and that it is there based not so much on occupation, as on personal and family prestige. Such differences in prestige are not, however, confined to social distinctions within the tribe, but extend to great differences in the repute and distinction of different kindred groups, according to their exploits and power.

It will be admitted, therefore, that in such barbaric societies as we have described, well-defined class distinctions are combined with a distinct social advantage of the more prolific stocks. Nor can we doubt on independent evidence that the families of the highest repute were in fact the most prolific. The high importance given to pedigree, and the care taken to preserve the names, even of a remote ancestry, is evidence of this; for such care would not generally be taken to preserve the memory of ancestors, if these were on the average less distinguished than their descendants. We can thus understand one of the factors which enables such peoples to base their social system upon blood relationship. This evidence indicates, moreover, not only a higher birth-rate but a greater natural increase, when the death- rate also is taken into account. It may well be suspected that the most eminent families suffered in war the highest death-rate, but in the severe losses which barbarian peoples suffer in times of dearth or enforced migration, the more powerful groups would certainly be at a substantial advantage ; and if, as we have seen, selection would tend to increase their innate fertility above that of the less distinguished groups, it is not surprising that we should be led to conclude that society was derived generation after generation, predominantly from its more successful members.

The most important consequence of this conclusion is that human evolution, at least in certain very ancient states of society, has proceeded by an agency much more powerful than the direct selection of individuals, namely the social promotion of fertility into the superior social strata. In particular, it is important that the qualities recognized by man as socially valuable, should have been the objective of such a selective agency, for it has hitherto only been possible to ascribe their evolutionary development to the selection of whole organized groups, comparable to the hives of the social insects. The selection of whole groups is, however, a much slower process than the selection of individuals, and in view of the length of the generation in man the evolution of his higher mental faculties, and especially of the self-sacrificing element in his moral nature, would seem to require the action of group selection over an immense period.

Heroism and the higher human faculties

The social ideas of all peoples known to us in the stage of emergence from the barbaric condition are dominated by the conception of heroism, and civilized peoples normally look back to so-called 'heroic ages' in which this conception moulded to an important degree the structure of society. The emotional influence of this idea has been so great, especially through the poetic tradition, that it is difficult to give a technically accurate characterization of the phenomenon without using terms charged with rhetorical associations. The reader must remember that we are not concerned to evaluate heroism either through praise or disparagement, but merely to consider its nature and implications as a sociological phenomenon.

The hero is one fitted constitutionally to encounter danger; he therefore exercises a certain inevitable authority in hazardous enter- prises, for men will only readily follow one who gives them some hope of success. [. . .]

An examination of the action of selection in barbarous societies in the tribal condition, reveals the possibility of the selection of the heroic qualities beyond the limits set by prudence, by a method analogous to that used in Chapter VII to explain the evolution of distasteful qualities in insect larvae. The mere fact that the prosperity of the group is at stake makes the sacrifice of individual lives occasionally advantageous, though this, I believe, is a minor consideration compared with the enormous advantage conferred by the prestige of the hero upon all his kinsmen. The material advantage of such prestige in barbarous society will, I think, scarcely be questioned ; it is evident in all the heroic literature ; it is directly evidenced by the deliberate vaunting of tribal achievements by professional poets; equally convincing is the great importance attached to genealogy in all such societies, by which the living boast their descent from the mighty dead. The positive aim before the hero is undying fame, he is therefore bound to all that is of good repute ; to the heroic spirit all material achievements are of lesser importance. Equally important with the phenomenon of heroism itself is the esteem in which it is held.

It is inevitable in a tribal state of society that certain stocks should distinguish themselves above others in the heroic qualities. If we may assume that such qualities do in fact benefit their tribesmen, which benefit can be most readily understood through the effects of prestige, then in a tribal society heroism may become a predominant quality. In this matter sexual selection seems in man to have played a most important role. I do not here specially stress the evidence of the poetic tradition, which, in spite of the reputation of poets for effemi- nacy, insists on associating heroism with true love. I should rather rely on the actual marriage customs of barbarous peoples. It should be emphasized that in such marriages the political element is more in evidence than the romantic, without their being the less dominated by the emotional reactions. A marriage is likely to involve blood feud obligations ; union with a powerful kindred is an essential asset. The corporate tribe is interested in the match, and sexual selection is most powerfully exerted by tribal opinion. The prestige of the con- tracting parties is all-important, and while this is partly personal, it also is largely tribal. The wooer relies upon his reputation even for the decision of the lady herself. Both in the Icelandic sagas and in the pre-Islamic poems, marriages are nearly always prompted by the political aspirations of the parties.

Such sexual selection by public opinion must influence many other qualities besides valour. Beauty, highmindedness and every other highly esteemed quality must be thereby enhanced. Its importance for us is that it influences the esteem in which the group of qualities most closely associated with heroism are held. Just as the power of discrimination of the female bird has been shown to be influenced by sexual selection pari passu with the ornaments which she appreciates, so in a barbarous society, in which the heroic qualities do possess an intrinsic tribal advantage, the power to appreciate and the proneness to admire such qualities will be enhanced, so long at least as reproduc- tion is actually greatest in the predominant families. The reader who will candidly compare the current attitude towards rash actions in any long civilized society with that among the peoples under dis- cussion, will scarcely doubt that the hero-worship of barbarous peoples was in fact a mental attitude which, however useless to modern man, played in their lives a very essential part. Changed conditions which have reversed the advantage of the heroic qualities, have also reversed the advantage of being able to recognize and appreciate them. It is obvious that the barbarous element in the tradition of our culture is that which emphasizes and indeed exaggerates, the natural inequality of man, whereas the religious and legal elements emphasize his civil equality. From the fact that the bar- barians valued more highly certain qualities of human character, it is a fair inference that they perceived such differences more clearly than do civilized men. Direct evidence on this point is necessarily elusive. On questions on which we are better informed than our ancestors it is easy for us to perceive the evidences of our advantage. If the reverse were the case, it would be easier for our ancestors than for ourselves to point out the difference. The only objective fact known to me relevant to the present issue is that moderns with highly trained powers of appreciation do find in the earliest examples of extant poetry a certain elusive quality in the delineation of character, which gives to such verse a recognizable supremacy in the particular literature to which it belongs.

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