Comparative genomics uncovers evolutionary drivers of locust migratory adaptation

Locust migration is one of the main causes of locust plagues. While existing research has highlighted the adaptive migratory capabilities of locusts, the evolutionary patterns of their migration remain elusive. This study aims to explore these evolutionary patterns of locust migratory behavior at the genomic level. To achieve this, we conducted comparative genomics analysis using genomic data from 10 locust species with diverse migratory tendencies.

We identified 1064 genes showing signatures of positive selection in five migratory locust species using a dN/dS model. The BUSTED-PH model revealed 116 genes associated with migratory phenotypes. Gene ontology enrichment analysis indicated that these genes were predominantly related to metabolism and mitochondria-related pathways through both methods. Additionally, the evolutionary rate (RER) analysis between migratory and non-migratory locusts revealed significant divergence in energy metabolism pathways. Notably, of the genes analyzed, the SETX gene consistently showed evidence of positive selection across all five migratory species.

The findings suggest that the evolution of migratory behavior is associated with increased selective pressure on metabolism and mitochondria-related pathways. Hundreds of genes undergo selective changes during repetitive transitions to migratory behavior. These findings enhance our understanding of the genetic and phenotypic relationships underlying different locust migratory behaviors, providing important data for understanding the biological mechanisms behind locust outbreaks.