The influence of body mass, diet, and phylogeny on lemur gestation length, age-at-first-birth, and interbirth interval length

Abstract

Life history theory is an important topic in primatology: studying a species’ life history enables us to understand their social system and can have major implications for conservation. As Malagasy lemurs are the most threatened group of mammals on earth, and understanding their life history traits and the biological factors that impact them may inform conservation efforts, this is an area of research with great consequence. This study examined the impact of body mass, diet, and phylogeny on the life history traits of gestation length, age-at-first-birth, and interbirth interval in 25 lemur species. I collected data on species from the families Indriidae, Cheirogaleidae, Lemuridae, and Lepilemuridae from previously published papers. The next step was to run linear regressions to determine how their body mass, diet, and phylogeny (measured using family) impact the aforementioned life history traits. An increased body mass was associated with a slow life history strategy, with a relatively late age-at-first-birth as well as a long gestation length and interbirth intervals. Diet did not have a significant impact on any of these life history traits, while phylogeny had a significant impact on gestation length, but not age-at-first-birth or interbirth interval. These results highlight how lemur life histories are distinctive from those of other nonhuman primates: due to the highly stochastic environment of Madagascar and the numerous unique traits lemurs possess, we cannot assume that trends seen in the life history traits of other primates will also be seen in lemurs