Social Individual Behavior Research Articles

A behavioral framework for the study of human disease.

A frame of reference for studying human disease is presented. An individual's social behavior serves as the orienting theme. Special forms of social behavior are in effect what tie an individual to his physical and social space, and alterations here can lead to disease. Causes of disease can thus be linked to behaviors of the individual. Although associated with basic changes in the psysiologies and chemistries of the individual, disease invariably comes to affect the individual's behavior and adaptation. Different ways in which such behavioral changes can be conceptualized are discussed. The individual relies on these behavioral changes as the data for evaluating his disease and deciding about medical treatment. A model of how an individual processes information about illness and makes decisions designed to alleviate his condition is presented. Finally, the rationale and value of keeping behavior and adaptation in mind when studying disease are discussed.

Haploidploidy and the evolution of the social insect.

Halminton (1) was apparently the first to appreciate that the synthesis of Mendelian genetics with Darwin's theory of natural selection had profound implications for social theory. In particular, insofar as almost all social behavior is either selfish or altruistic (or has such effects), genetical reasoning suggests that an individual's social behavior should be adjusted to his or her degree of relatedness, r, to all individuals affected by the behavior. We call this theory kinship theory. The social insects provide a critical test of Hamilton's kinship theory. When such theory is combined with the sex ratio theory of Fisher (9), a body of consistent predictions emerges regarding the haplodiploid Hymenoptera. The evolution of female workers helping their mother reproduce is more likely in the Hymenoptera than in diploid groups, provided that such workers lay some of the male-producing eggs or bias the ratio of investment toward reproductive females. Once eusocial colonies appear, certain biases by sex in these colonies are expected to evolve. In general, but especially in eusocial ants, the ratio of investment should be biased in favor of females, and in it is expected to equilibrate at 1 : 3 (male to female). We present evidence from 20 species that the ratio of investment in monogynous ants is, indeed, about 1 : 3, and we subject this discovery to a series of tests. As expected, the slave-making ants produce a ratio of investment of 1 : 1, polygynoys ants produce many more males than expected on the basis of relative dry weight alone, solitary bees and wasps produce a ratio of investment near 1 : 1 (and no greater than 1 : 2), and the social bumblebees produce ratios of investment between 1 : 1 and 1 : 3. In addition, sex ratios in monogynous ants and in trapnested wasps are, as predicted by Fisher, inversely related to the relative cost in these species of producing a male instead of a female. Taken together, these data provide quantitative evidence in support of kinship theory, sex ratio theory, the assumption that the offspring is capable of acting counter to its parents' best interests, and the supposition that haplodiploidy has played a unique role in the evolution of the social insects. Finally, we outline a theory for the evolution of worker-queen conflict, a theory which explains the queen's advantage in competition over male-producing workers and the workers' advantage regarding the ratio of investment. The theory uses the asymmetries of haplodiploidy to explain how the evolved outcome of parent-offspring conflict in the social Hymenoptera is expected to be a function of certain social and life history parameters.

NADEL ON THE AIMS AND METHODS OF SOCIAL ANTHROPOLOGY

IN this paper I discuss critically the late Professor Nadel's views on the aims and methods of social anthropology. These are to be found in his long and diffcult book The Foundations of Social Anthropology.1 Only two problems raised by Nadel will be discussed. (I) What are the aims of social anthropology? (2) What, in general, will a characteristic attempt to achieve these aims look like? Nadel's answer to (I) is that social anthropology aims at: (a) describing and (b) explaining rational behaviour. He argues that there is such a dose relationship between these two aims that they can be treated as one in the solution to (2), as follows. An explanation is to be effected by means of general descriptive laws, which are 'fit' or 'required' correlations reached by induction. He then argues that we explain the social behaviour of individuals by means of laws on non-social (i.e. psychological) levels. We explain social institutions in terms of laws specifying the ultimate purpose they serve in society.