Evolutionary analyses of ethnic solidarity: an overview

People and Place, June, 2008 by Frank Salter

The mechanisms that direct altruism towards kin and tribe are receiving more attention from evolutionary psychologists. There is cross-cultural evidence that ethnic favouritism conditions the moral emotions such that norm violations by fellow ethnics against an outsider are punished less than the reverse. The set of findings is not fully consistent with any existing theory, though the authors point to ways in which multi-level selection and kin-selection theories could be applied. (39) Group reputation for altruistically punishing external aggression might have been a factor in inter-tribal relations. If so this would support a model of extended kin selection. (40)

Most psychological contributions to ethnic studies have not been evolutionary. Knowledge of social identity mechanisms and collectivism, both salient features of ethnic solidarity, were developed without reference to natural selection, though they generally provide support for an evolutionary interpretation. (41) The same applies to Lawrence Hirschfeld's theory of innate categorisation of descent groups, including races. His ingenious social psychological experiments show that uninstructed five-year-olds distinguish inherited from acquired characteristics. Hirschfeld concludes that humans have an innate special-purpose competence for identifying and representing human descent groups. (42) This theory too makes sense from the perspective of evolutionary psychology which classifies Hirschfeld's hypothesised psychological mechanism as a 'domain-specific' cognitive ability or a 'mental module', as opposed to 'domain-general' ability or general intelligence. The ethnic predispositions discussed in this section fit the description of mental modules since they are universal, appear in early childhood and are produced by rapid unconscious thought processes. (43)

EVOLUTIONARY ANTHROPOLOGY

Van den Berghe's contributions are anthropological but have already been discussed under 'sociobiology'. Evolutionary perspectives have entered the mainstream of anthropology, not just in physical anthropology but in studies of social behaviour, such as Wiessner's study of Kalahari Bushmen's reciprocal networks that favour kin for long-range exchange. (44) In a cross-cultural study Cashdan tested the widely held view that ethnocentrism entails xenophobia. (45) She found that attacks by other groups increase hostility but that famine increases ethnic loyalty without usually antagonising group relations. The two behaviours are weakly linked.

There is a strong correlation between linguistic and genetic phylogeny. Cavalli-Sforza and others have shown that divisions and subdivisions of languages correspond remarkably well with populations as defined by genetic distances and boundaries of steep genetic gradients. (46) Since language is an ethnic marker this is strong evidence that the ethnic myth of common descent usually has a basis in fact.

Evolutionary anthropology answered a vital question: how great or small is ethnic kinship, the genetic similarity within ethnic groups? Knowing this quantity allows Hamilton's Rule to be applied to ethnic altruism, that is, to determine how many co-ethnics and altruist must save for his self-sacrifice to be adaptive. Recall that Dawkins failed to answer the question or even formulate it, despite it being the starting point of the study of inclusive fitness processes among ethnic groups. Jones showed that social controls on free riders can make it adaptive to invest in large groups which are genetically similar. (47) Harpending showed that ethnic kinship varies with the populations being compared. On a global scale it typically approximates that of cousins in an outbred population and sometimes higher. (48)