Lemur behaviour informs the evolution of social monogamy

Area of Science:

• Evolutionary biology
• Primatology
• Behavioral ecology

Background:

• Previous studies on the evolution of social monogamy in mammals yielded contradictory results.
• These studies overlooked the significance of social bond quality between pair-partners.
• Understanding primate social evolution requires nuanced approaches to pair-bonding.

Purpose of the Study:

• To investigate the evolutionary origins of social monogamy in Malagasy primates.
• To examine how variation in intersexual bond quality influences transitions to pair-living.
• To resolve conflicting conclusions from prior comparative analyses of social monogamy.

Main Methods:

• Comparative analysis of Malagasy primate social structures.
• Field studies focusing on variable intersexual bond quality.
• Reconstruction of evolutionary pathways to pair-living from different ancestral states.

Main Results:

• Evidence for independent evolutionary transitions to pair-living from both solitary and group-living ancestors in lemurs.
• Identification of four cumulative steps in the evolutionary transition from solitary to pair-living.
• Demonstration that incorporating social bond variation resolves contradictions in previous evolutionary models.

Conclusions:

• Social monogamy in primates has evolved through multiple, independent pathways.
• Social bond quality is a critical factor in understanding the evolution of pair-living.
• This study provides a refined framework for analyzing the evolution of social systems in mammals.