Thermal Tolerance in Burying Beetles
Advisor Information
Claudia Rauter
Location
Dr. C.C. and Mabel L. Criss Library
Presentation Type
Poster
Start Date
6-3-2015 2:00 PM
End Date
6-3-2015 3:30 PM
Abstract
As global temperatures are predicted to increase, so are the occurrences of extreme events like heat waves. On the Great Plains, heat waves have become more common and the last frost generally occurs earlier in spring. These climate changes have an impact on all living organisms, especially ectothermic insects like burying beetles. Exposed to extreme temperatures, burying beetles reduce their metabolic rate to a minimum and enter a coma to protect themselves from these extreme conditions. Once in a coma, the beetles are no longer able to reproduce or search for resources to survive. The purpose of this study was to determine the range of temperatures where two burying beetle species, native to the Great Plains, are active: Nicrophorus marginatus, which is found in grasslands and N. orbicollis which occurs in forests and grasslands. By exposing beetles from both species to gradually increasing or decreasing temperatures, respectively, I determined the maximum and minimum temperature (Tmax and Tmin), where the beetles stopped moving. For both species Tmin was at about 4.5°C (N. marginatus 4.6±0.7°C and N. orbicollis 4.2±0.4°C) allowing them to become active at temperatures slightly above freezing thus taking advantage of earlier spring arrival. Tmax was about 40°C with N. marginatus having a higher Tmax (40.4±0.4°C) than N. orbicollis (39.4±0.5°C). A Tmax of 40°C suggests that both species are physiologically able to survive the current heat waves. Future studies will need to determine the fitness consequences of an extended activity period in combination with increased heat waves.
Thermal Tolerance in Burying Beetles
Dr. C.C. and Mabel L. Criss Library
As global temperatures are predicted to increase, so are the occurrences of extreme events like heat waves. On the Great Plains, heat waves have become more common and the last frost generally occurs earlier in spring. These climate changes have an impact on all living organisms, especially ectothermic insects like burying beetles. Exposed to extreme temperatures, burying beetles reduce their metabolic rate to a minimum and enter a coma to protect themselves from these extreme conditions. Once in a coma, the beetles are no longer able to reproduce or search for resources to survive. The purpose of this study was to determine the range of temperatures where two burying beetle species, native to the Great Plains, are active: Nicrophorus marginatus, which is found in grasslands and N. orbicollis which occurs in forests and grasslands. By exposing beetles from both species to gradually increasing or decreasing temperatures, respectively, I determined the maximum and minimum temperature (Tmax and Tmin), where the beetles stopped moving. For both species Tmin was at about 4.5°C (N. marginatus 4.6±0.7°C and N. orbicollis 4.2±0.4°C) allowing them to become active at temperatures slightly above freezing thus taking advantage of earlier spring arrival. Tmax was about 40°C with N. marginatus having a higher Tmax (40.4±0.4°C) than N. orbicollis (39.4±0.5°C). A Tmax of 40°C suggests that both species are physiologically able to survive the current heat waves. Future studies will need to determine the fitness consequences of an extended activity period in combination with increased heat waves.