Behaviors are often correlated within broader syndromes, creating the potential for evolution in one behavior to drive evolutionary changes in other behaviors. Despite demonstrations that behavioral syndromes are common, this potential for evolutionary effects has not been demonstrated. Here we show that populations of field crickets (Gryllus integer) exhibit a genetically conserved behavioral syndrome structure, despite differences in average behaviors. We found that the distribution of genetic variation and genetic covariance among behavioral traits was consistent with genes and cellular mechanisms underpinning behavioral syndromes rather than correlated selection. Moreover, divergence among populations’ average behaviors was constrained by the genetically conserved behavioral syndrome. Our results demonstrate that a conserved genetic architecture linking behaviors has shaped the evolutionary trajectories of populations in disparate environments—illustrating an important way for behavioral syndromes to result in shared evolutionary fates.

Behavior of individual Gryllus integer crickets were measured and crickets bred according to a maternal & paternal half-sib design.

Please see associated github repository for code and rds files for MCMC outputs. 

https://github.com/DochtermannLab/G-PopComparison