A model of mutual tolerance and the origin of communal associations between unrelated females

• Published in: Journal of insect behavior 1998-03, Vol.11 (2), p.265-286
• Main Authors: Robertson, I.C, Robertson, W.G, Roitberg, B.D
• Format: Article
• Language: English
• Subjects: Animal ethology; Animal reproduction; Biological and medical sciences; BIOLOGICAL COMPETITION; BOUSIER; BROOD PARASITISM; COMMUNAL BREEDING; COMPETENCIA BIOLOGICA; COMPETITION BIOLOGIQUE; COMPORTAMIENTO SEXUAL; COMPORTAMIENTO SOCIAL; COMPORTEMENT SEXUEL; COMPORTEMENT SOCIAL; DIMENSION; DIMENSIONS; Dung; DUNG BEETLES; Ecological conditions; ESCARABAJOS DEL ESTIERCOL; EVOLUCION; EVOLUTION; EVOLUTIONARILY STABLE STRATEGY; Females; Fundamental and applied biological sciences. Psychology; GAME THEORY; General aspects; GENETIC ALGORITHMS; INTRASPECIFIC COMPETITION; KLEPTOPARASITISM; MATEMATICAS; MATHEMATICAL MODELS; MATHEMATICS; MATHEMATIQUE; MODELE MATHEMATIQUE; MODELOS MATEMATICOS; NESTING; Nests; NICROPHORUS; NIDIFICACION; NIDIFICATION; Offspring; PARASITISM; PARASITISME; PARASITISMO; Psychology. Psychoanalysis. Psychiatry; REPRODUCCION SEXUAL; REPRODUCTION SEXUEE; REPRODUCTIVE SKEW; REPRODUCTIVE TOLERANCE; SEXUAL BEHAVIOUR; SEXUAL REPRODUCTION; SILPHIDAE; SIZE; SOCIAL BEHAVIOUR; SOCIAL DOMINANCE
• ISSN: 0892-7553; 1572-8889
• DOI: 10.1023/A:1021052125128

We use a genetic algorithm model employing game theory to explore the ecological conditions favoring reproductive tolerance between two unrelated females that meet at a nesting site (i.e., breeding resource). Each female adopts one of three strategies: (1) fight for exclusive use of the nest, (2) tolerate the other female and breed communally, but fight back if attacked, or (3) leave in search of new breeding opportunities. Nests vary in the number of offspring they can support and their probability of failure due to discovery by competitors. The model predicts that communal associations are most likely to arise when (1) the benefits of nest sharing to females exceed the losses to individual reproduction, (2) additional nesting sites are rare, (3) females have limited clutch sizes, and (4) dominant females are able to skew reproduction in their favor. The amount of reproductive skew a dominant (larger) female can acquire while maintaining a communal association is predicted to increase when the asymmetry in fighting ability between females increases, and at nests that have a relatively high probability of nesting success for solitary females. When the losers of fights can parasitize the winner's brood, dominant females must reduce reproductive skew to promote a communal relationship. We discuss the ability of our model to predict patterns of facultative communal behavior in burying beetles (Silphidae; Nicrophorus spp.), as well as the absence of communal behavior in dung beetles (Scarabaeidae). [PUBLICATION ABSTRACT]