Acrobatic courtship display coevolves with brain size in manakins (Pipridae)

Area of Science:

• Evolutionary Biology
• Neuroscience
• Ornithology

Background:

• Sexual selection in manakins (Pipridae) favors complex acrobatic displays.
• Research has focused on vocal courtship, with less known about non-vocal motor control.
• Manakin displays vary in complexity, motor elements, sound production, cooperation, and site construction.

Purpose of the Study:

• To test if sexual selection for complex motor displays has led to larger brains in manakins.
• To investigate the link between acrobatic display evolution and brain size in birds.
• To expand understanding of how sexual selection impacts motor behavior and neural systems.

Main Methods:

• Comparative analysis of brain size and display complexity across 12 manakin species and one flycatcher.
• Phylogenetic control to account for evolutionary relationships.
• Statistical modeling to assess the relationship between display complexity and relative brain weight.

Main Results:

• Display complexity positively predicts relative brain weight, even after controlling for body size and phylogeny.
• Evidence suggests brain size evolved to support motor, sensorimotor, perceptual, and cognitive aspects of displays.
• This study provides the first evidence for sexual selection driving brain size evolution through acrobatic motor behavior in birds.

Conclusions:

• Sexual selection for complex acrobatic displays is a significant driver of brain size evolution in manakins.
• Brain evolution in Pipridae is linked to the demands of elaborate courtship motor behaviors.
• This finding broadens our understanding of the evolutionary pressures shaping neural complexity in avian species.