Briefly, the law of Avoidance concerns (more particularly) the relation 'inter se,' from a sexual point of view, of the male and female offspring of any given parents. In other words it determines the mutual attitude to the females within a (single) family group dominated by a male head.

Before, however, entering into the argument in this connection, it will be desirable to make a paraphrase on Mr. Darwin's dictum as to the social condition of man in the animal stage in general, and more particularly in regard to his intermarital relations, and to compare this with that of actual mammals. It is to be noted that he does not pronounce definitely as to whether, in the era of pure animalism, the original type of man's ancestor was social or non-social in habit. But we may judge from the extract already made from the Descent of Man that Darwin evidently inclines to the opinion that, even primitively, he was a social animal, as seemingly more in accord with the present eminently social conditions.

The very significant counter-fact, however, remains, that none of the actual anthropoids, as far as regards the adult males, are in any way social or even gregarious; the conclusion thus seems evident that, like these his nearest compeers of to-day, man was on the contrary a non-social animal, and that, as with the gorilla, only one grown male would have been seen in a band. We must then imagine our more or less human ancestor, roaming the forest in search of daily food, as a solitary polygamous male, with wife or wives and female children; the unsocial head of a solitary isolated group.

With equal strength and probably already greater cunning than any actual animal of to-day, he had perhaps acquired dominance over most of the other beasts of the field. The patriarch had only one enemy whom he should dread, an enemy with each coming year more and more to be feared—deadly rivals of his very own flesh and blood, and the fruit of his loins—namely, that neighbouring group of young males exiled by sexual jealousy from his own and similar family groups—a youthful band of brothers living together in forced celibacy, or at most in polyandrous relation with some single female captive.[1] A horde as yet weak in their impubescence, they are, but they would, when strength was gained with time, inevitably wrench by combined attacks, renewed again and again, both wife and life from the paternal tyrant. But they themselves, after brief communistic enjoyment, would be segregated anew by the fierce fire of sexual jealousy, each survivor of the slaughter relapsing into lonely sovereignty, the head of the typical group with its characteristic feature of a single adult male member in antagonism with every other adult male. Now it can be shown that this vicious circle of the stream of social life is common to most mammals. The facts of the circumstance can be most easily observed amidst the half-wild, half-domesticated animals met with in colonial farming experience, in New Caledonia, for instance, where European horses and cattle have been allowed to return almost to a state of nature.

In this respect the economy of life in a herd of even such gregarious creatures as the bovine race, is a very curious and instructive study. There is no fact more striking than the subordination in which the younger bulls are kept; as long as they are at all tolerated in the herd by its patriarch, their intercourse with the females is most limited, and only takes place by stealth and at the risk of life and limb.

Nothing, as breeders are aware, is so fatal to the well-being of a herd, or leads so quickly to degeneration, as the perpetuation of the race by immature males. That procreation should be the act of the robust adult alone, is evidently an axiom with nature herself in successful production; it is doubtless of the highest importance to keep up the normal standard of strength and size. As a fact, the presence of the immature male among a herd of cattle is only permitted whilst he is still quite impubescent. Then banishment by the master of the herd is inevitable at a later stage. These exiles, although thus apart from the main herd, remain in touch with it, so to speak, and we find in consequence, in continual proximity of the troop of the patriarch and his females, a small band of males, which, as is evident from their colour and general physical resemblance, are its direct product. The relations between this mob and the old male are always strained, the latter has constantly to be on the watch to shield his marital rights.

For long the mere menace of his presence suffices for such protection, but with age—the young bulls becoming more bold—struggles take place which sooner or later, from mere force of numbers, end in the rout or death of the parent. We may here cite the mention made by Mr. Darwin[2] of Lord Tankerville's account of the battles of the wild bulls in Chillingham Park: 'In 1861 several contended for mastery, and it was observed that two of the younger bulls attacked in concert the old leader of the herd, overthrew and disabled him, so that he was believed by the keepers to be lying mortally wounded in a neighbouring wood. But a few days afterwards one of the young bulls approached the wood alone, and then the monarch of the chase, who had been lashing himself up for vengeance, came out and in a short time killed his antagonist. He then quietly joined the herd, and long held undisputed sway.' I may add from my own observation among half-wild herds in the colonies, that often when the old patriarch is not absolutely killed in such cases, he is forced to quit the herd. He then becomes a solitary exile, always exceptionally savage and dangerous to approach or molest. It seems to me probable that we have here an explanation of the occurrence of the existence of the well-known 'rogue' elephant, which is always a male and notoriously dangerous.

One important fact must here, however, be noted; that before such death or exile takes place, and the sons reach an age which enables them successfully to dispute the supremacy of the father, the daughters have reached puberty and borne produce to the sire—this matter, as will be seen later, has an important bearing on our general argument—on our theory of Primal Law. Amongst horses, again, which have become wild, exactly the same facts are to be observed. Each herd has one head, and this, as natural selection would imply, is the most powerful stallion; he is the master and owner of the females, and this mastery he retains until overpowered by other males, which, as before, are almost invariably his own progeny. In fact, any strange male would probably have first to run the gauntlet of this outlying herd of exiled sons before he could reach the father. It is, however, again to be noted that he is rarely thus overpowered by even the combined efforts of his sons, before his daughters have reached such an age as to have produced offspring to their father.

This system of sequence of generations in breeding is, indeed, so universal in a state of nature amongst all animals, as to seem to point to the fact that in-breeding between father and daughter cannot be so prejudicial as some believe. Its efficacy in type-fixing is at least very great, if, as experiments of my own in pig-breeding on these lines would lead me to think, the question of prepotency is merely a matter of such close in-breeding repeated for generations. We may note here that if, as is probable, the produce, on the contrary, of a full brother and sister are degenerate, nature seems to attempt to prevent its occurrence. On the succession of the sons to the father's rights, speedy conflicts from sexual jealousy arise amidst the former and lead to a rapid segregation of the herd, in which the chances of own brother and sister continuing to mate are slight. Until this segregration, however, does take place, nothing is more curious to watch than the attitude and relations of these young males among themselves, the oldest and strongest claiming prior marital rights, but no more.

The same phenomena in social economy may be observed with even greater intensity in lower ranks of life than the quadrupeds. For instance, in a large flock of game fowl which I had an opportunity to observe closely for several years, during which they had nearly relapsed into a state of nature, there was an exact reproduction of all these details. There existed the same division into small family groups, each headed by an adult male, the same subordination imposed on the junior males of their banishment at puberty, as also their inevitable combined attack, when sufficiently powerful, on their paternal enemy. His death resulted in the same communistic assumption of his rights, with a subsequent disruption, from jealousy, into the typical smaller and separate groups.