Abstract
A study was conducted to quantify the relationship between ambient air temperatures and adult internal body temperatures of three rangeland grasshoppers near Three Forks, MT. Results show a strong non-linear relationship between air and body temperatures over the range of temperatures normally encountered during the adult stage (approximately 2–42°C). Observations and historical data indicate the considerable influence of behavioral modification that results in grasshoppers attempting to maintain an optimal temperature range that minimizes development time. Results should be of interest to insect ecologists and those studying grasshopper biology and population dynamics.