Thermal Preference as it Relates to Body Mass of Gryllus Pennsylvanicus

Abstract

The purpose of this study was to determine if body size affected the thermal preference of Gryllus Pennsylvanicus. From this, it was hypothesized that Gryllus Pennsylvanicus of a lower mass will spend more time in the hot zone than Gryllus Pennsylvanicus with a larger mass. This was predicted because Bergmann’s rule states that larger sized species live in colder environments, while smaller sized species live in warmer environments (Pincheira- Donoso et al. 2008).   It was accomplished by obtaining 10 crickets that were split into two groups based on body mass. These crickets were then placed into thermal zone boxes for 300 seconds to determine their thermal preference. On average, the field crickets of smaller mass spent more time in the hot zone than the crickets of larger mass by 29.6 seconds. This means that the hypothesis was supported. This could mean that smaller field crickets will remain in the in hotter climates due to thermal preferences.