John Hurrell Crook

Social organization and the environment: Aspects of contemporary social ethology

Summary 1. A major development within the ethology of the last decade focusses attention upon the relations between social behaviour, ecology and population dynamics. This field may be termed ‘social ethology’ following an early but neglected usage of the term by Waxweiler at the start of the century. 2. Contemporary social ethology comprises three interdependent perspectives, socio-ecology, socio-demography and the study of social processes within natural and experimental groups. 3. In socio-ecology recent studies reveal that close correlations exist between the forms of avian and mammalian social organizations and their respective ecological niches. In particular the adaptive significance of certain mammalian societies comprising, on the one hand, multimale reproductive units and, on the other, those made up of one-male and all-male units is discussed and explanatory hypotheses derived from primate and ungulate data briefly considered. 4. In socio-demography research suggests that socially mediated mortality is of greater significance in the density-dependent control of bird and mammal numbers than had formerly been thought. The relations between ecological factors extrinsic to and social factors intrinsic to a social organization may be modelled in the form of open adaptive cybernetic systems rather than expressed in terms of analogies to closed mechanical or physiological systems. 5. Studies of social processes in non-human primate groups suggest that some form of role analysis may prove heuristic. The relations between dominance status, affiliative and kinship relations, social subterfuge and competition-contingent cooperation are discussed in an attempt to outline the dynamics of social change within relatively stable group structures. 6. ‘Human ethology’ seems at present to lack adequate definition as an academic discipline. Social ethology may provide the essential biological basis for future research in this area.

Mammalian social systems: Structure and function

Abstract Mammalian societies are complex socio-ecological systems controlled by the interactions of numerous internal constraints and external factors. We present a simple model describing these systems functionally in terms of the adaptive behavioural strategies for resource exploitation, predation avoidance and mating and rearing of young to maturity shown by the individuals that comprise them. The relations between species-specific limitations on the range of potential individual social behaviour and the environmental variables to which the system is responsive are analysed and hypotheses from correlational and analytical field studies examined. We advocate the continued development of sophisticated systems-analytical approaches to societal analysis taking into account the contrasting informational provenance of factors of different types. This is preferred to either an over-emphasis on environmental determination or excessively formalised neo-darwinian modelling based on assumptions from genetics and selection theory alone.

The effects of luteinizing hormone, oestrogen and ovariectomy on the agonistic behaviour of female Quelea quelea

Abstract Previous work with male Quelea showed that agonistic behaviour in relation to individual distance is controlled by luteinizing hormone (LH), rather than by testosterone, and that males are more aggressive than females. Experiments with female groups are reported which show that: (a) LH injections increase aggressive encounter frequency; (b) ovariectomy in the breeding season (but not outside it) also increases encounter frequency; and (c) oestrogen injections decrease encounter frequency. The effects of LH were shown to be specific to agonistic responses rather than mediated through changes in activity. Correlations between changes in natural hormone levels and encounter frequency support the injection findings. These results are consistent with the hypothesis that LH controls aggressive encounters over individual distance in the female as in the male and that oestrogenic inhibition of this LH-mediated aggressiveness is a cause of female subordination and the lower encounter frequency found in female groups. The annual cycle of encounter frequency is described and the significance of different systems of hormonal control is discussed.

The indigenous psychiatry of Ladakh, Part I: Practice theory approaches to trance possession in the himalayas

Abstract In traditional Ladakh (NW India) psychological distress is treated as possession necessitating identification and expulsion or control of the possessing agent. On marriage young women are commonly afflicted and men suffering stress from a variety of causes may also be affected. Aid for an individual may be sought from various helpers but a common treatment occurs in seance with a shamanic oracle‐healer (Iha.pa). These oracles are women or men who have themselves passed through an initiatory possession. Appeal may further be made to a high lama of a local monastery who places a persistent possessing agent under vow to manifest only when requested in order to help others through oracular pronouncements or healing. To achieve this the afflicted must undergo training with a senior lha.pa. Current theory of shamanic behaviour is examined to suggest that the prime mover here is psychological pressure within gender, family or social relations requiring an adjustment in an individuals sense of identity. ...

Primate societies and individual behaviour

Abstract This paper reviews briefly some salient findings concerning the relations between ecology and social structure of primate populations. Referring specifically to open country ground dwelling macaques and baboons correlations between a multi-male reproductive unit and a one-male unit and relatively food rich and food poor environments respectively are found. Predation and the availability of safe sleeping sites also affect structure. Intraspecific constrasts in social organization may be pronounced and appear to relate to well-defined differences in habitat. The maintenance and division of social groups is dependent upon population (group) size, the type of structure and the pattern of affiliative relations within groups. These determine the manner of group splitting. Kinship is considered a vital factor in maintaining the stability of social relations in these primate groups. In the heat of experimental research it is easy to forget that the meaning of an experiment rests upon full comprehension of the norms of a species behaviour. As primate social studies develop in the laboratory they must be matched with field studies of an equal sophistication. For these to be effective careful selection of personnel, resources for their training and an adequate financial backing are essentials.