Introduction and General Methods 

The subject of animal personality is under intense study; the idea that behavioral phenotypes between individuals can differ, but that of a single individual, i.e., its personality, is consistent over time and contexts; for example, bold animals remain bold while shy animals remain shy1-3. Personality traits can significantly impact an animal’s ability to find food, obtain shelter, evade predators, and reproduce.  

Animals usually exhibit sets of correlated behaviors, or behavioral syndromes, which form their overall personality3,4. Such syndromes have been documented in a range of animals, including mammals, birds, reptiles, amphibians, fish, and insects1. For example, bold male crickets are more exploratory and aggressive than shy males5,6; therefore, male crickets can exhibit a bold-exploratory-aggressive behavioral syndrome.

Our lab uses the cricket A. domesticus to study animal personalities. 

We hypothesized that bold male crickets would be more likely to win fights and become socially dominant against timid male crickets. 

Acheta domesticus crickets were raised in our colony in Pearson Hall. Immature males and females are housed in boxes of 50-100 (Fig. 1) in a walk-in incubator maintained at 250C with a 12L:12D light cycle. They were provided with food and water ad libitum. 

Once crickets became adults (D1), males and females were pulled from the colony and isolated in individual deli containers (Fig. 2) and provided with food and water. Deli containers were placed in an incubator at 250C, 12L:12D. Once crickets reached sexual maturity (D9), they were used in boldness trials. On D10, bold male crickets were paired with timid male crickets in fight trials.