Primate Social Groups as Biological Islands

Abstract

The intestinal protozoan faunas of 11 social groups of Cercocebus albigena, 3 groups of Ceropithecus mitis, 3 groups of Cercopithecus ascanius, 2 groups of rain forest and 4 groups of savannah Papio anubis are documented. All individuals in a particular social group exhibit identical protozoan faunas. All social groups of each species, except the savannah P. anubis, exhibit intergroup differences in the composition of their protozoan faunas. The number of intestinal, protozoan species in Cercocebus albigena social groups is a function of group size. The similarity between the protozoan faunas of different C. albigena groups is related to the density of the social groups and types of land tenure in particular localities. Past social history of C. albigena groups may have some influence on the level of similarity of different groups' faunas. Entrance of a nongroup member into a group of Cercopithecus mitis resulted in an increase in the species richness of the group's protozoan fauna. Group fission may result in reduction of a group's protozoan species richness. All groups of savannah Papio anubis exhibit identical protozoan faunas. I argue that this is because savannah P. anubis has a higher rate of exchange of individuals between groups than has been recorded for the rain forest primates under consideration. I hypothesize that the differing rates of exchange are due to disease—related selection against traits which result in high rates of individual exchange among rain forest primate groups. Primate social groups are functionally biological islands; the species of their protozoan faunas changes according to group size and levels of protozoan migration between groups.

The development of immunity in a social insect: Evidence for the group facilitation of disease resistance

“…Sociality compounds disease risks caused by increased rates of infection transmission (27,28) and genetic relatedness (3,4,29), but there is little evidence that grouping lowers pathogen-related death hazards. In some gregarious lepidopteran species, grouping appears to stimulate pathogen resistance mechanisms, including the prophenoloxidase enzyme cascade and cuticular melanization (30), and in honey bees ''fever'' (elevated nest temperature) is generated as a colonylevel response to prevent chalk brood, which is caused by a heat-sensitive fungus (31).…”

Do Animals Living in Larger Groups Experience Greater Parasitism? A Meta-Analysis

“…Levels of infestation and infection by parasites differ among social groups, populations, and species, and researchers have long been interested in understanding the factors that account for variation in parasitism (Freeland 1979;Brown and Brown 1986;Poulin 1995;Nunn and Altizer 2006). A prominent hypothesis offered to explain this variation postulates a link between parasitism and gregariousness (Freeland 1979;Møller et al 1993;Loehle 1995;Altizer et al 2003).…”

“…A prominent hypothesis offered to explain this variation postulates a link between parasitism and gregariousness (Freeland 1979;Møller et al 1993;Loehle 1995;Altizer et al 2003). Living in a larger group may increase parasitism through several mechanisms.…”

Parasite abundance and diversity in mammals: correlates with host ecology.

“…[2][3][4][5][6][7][8]. For endangered mammals in protected areas, the only practical alternative to obtaining samples from culled individuals is fecal examination for parasite propagules (9), despite some limitations of this method (10). There have been few attempts to quantify measures of parasite abundance and diversity based on fecal analyses (11).…”