Identification of a major gene regulating complex social behavior

Area of Science:

• Evolutionary biology
• Behavioral genetics
• Social insect behavior

Background:

• Colony queen number is a key aspect of fire ant social structure.
• Worker genotypes at the Gp-9 gene are linked to colony queen number.

Purpose of the Study:

• To investigate the role of the Gp-9 gene in regulating social organization and queen number in fire ants.
• To understand the molecular basis of social behavior in fire ants.

Main Methods:

• Sequencing of the Gp-9 gene.
• Analysis of Gp-9 sequence evolution in South American fire ant species.
• Examination of Gp-9's role in pheromone binding and chemical recognition.

Main Results:

• The Gp-9 gene encodes a pheromone-binding protein essential for recognizing nestmates.
• Differences in Gp-9 genotypes correlate with variations in queen recognition and number regulation among fire ant social forms.
• Evidence suggests positive selection drove the divergence of Gp-9 alleles, impacting social organization.

Conclusions:

• The Gp-9 gene is a major factor in the evolution of social organization in fire ants.
• Single genes can significantly influence complex social behaviors and evolution.
• Understanding Gp-9's function provides insights into the genetic underpinnings of sociality in insects.