Lemur behaviour informs the evolution of social monogamy

Recent comparative analyses reached contradictory conclusions about the evolutionary origins of social monogamy in primates and other mammals, but they ignored variation in social bond quality between pair-partners. Recent field studies of Malagasy primates (lemurs) with variable intersexual bonds indicate independent evolutionary transitions to pair-living from solitary and group-living ancestors, respectively, as well as four cumulative steps in evolutionary transitions from a solitary life style to pair-living that resolve some contradictory results of previous studies.