PERSONALITY AND ITS GENETIC FACTORS IN A JUMPING SPIDER

Abstract

Animal personality has received increasing interest in biology over the past two decades. However, evolutionary mechanisms and the genetic basis of personality in natural populations remain poorly understood. The jumping spider, Portia labiata, exhibits consistent individual differences in aggression and boldness with no correlation between these traits. I found that individual aggression and ecological contexts (i.e., task difficulty and prey behaviour type) jointly determine decision-making and foraging performance, suggesting that natural variation in aggression is maintained by context-dependent fitness consequences. I next used multiple approaches to study the genetic basis of individual aggression and boldness. This research revealed that spider aggression is regulated by serotonin receptors and may have coevolved with immune systems. My research also identified sex-specific genetic basis of boldness which are regulated by distinct genes. Taken together, this thesis sheds new insights on the evolutionary and genetic mechanisms of behavioral variation in wild invertebrates.