Dominance Rank Reversals and Rank Instability Among Male Lemur catta: The Effects of Female Behavior and Ejaculation

摘要

In this study, dominance rank instability among male Lemur catta during mating was investi_gated. Also, data on agonism and sexual behavior across five consecutive mating seasons in a population of L. catta on St. Catherines Island, USA, were collected. Instances of male rank instability were categorized into three types. Type I consisted of a temporary switch in the dominance ranks of two males, which lasted for a pe_riod of minutes or hours. Type 2 dyadic male agonistic interactions showed highly variable outcomes for a pe_riod of time during which wins and losses were neither predictable nor consistent. Type 3 interactions consisted of a single agonistic win by a lower-ranked male over a more dominant male. More Type 2 interactions (indi_cating greater dominance instability) occurred when males had not spent the previous mating season in the same group, but this trend was not statistically signifi_cant. The majority of periods of male rank instability were preceded by female proceptivity or receptivity directed to a lower-ranked male. As such, exhibition of female mate choice for a lower-ranking male appeared to incite male_male competition. Following receipt of female proceptivity or receptivity, males who were lower-ranking took significantly longer to achieve their first agonistic win over a more dominant male than did males who were higher-ranked. Ejaculation frequently pre_ceded loss of dominance. In conclusion, temporary rank reversals and overall dominance rank instability com_monly occur among male L. catta in mating contexts, and these temporary increases in dominance status appear to positively affect male mating success. Am J Phys Anthropol I38:293-305, 2009. _ 2008 Wiley-Liss, Inc.