The role of environmental heterogeneity in the evolution of life history strategies of the striped ground cricket /

• Main Author: Bradford, Michael J.
• Format: Others
• Language: en
• Published: McGill University 1991
• Subjects: Crickets > Development.; Crickets > Evolution.; Temperature > Physiological effect.
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70319

I examined the effect of heterogeneity in the thermal environment on the life history of the cricket Allonemobius fasciatus. Variation in the life cycle was the result of a mixture of phenotypic plasticity and genetic differentiation in phenology-related traits along a latitudinal cline in growing season. Females from a partially bivoltine population have a conditional life history because they can adjust the proportion of diapause eggs in accordance with the likelihood that a second generation will grow and reproduce before winter. The thermal environment is not variable enough to result in the evolution of a marked bet hedging response, as is predicted by theory. A quantitative genetic analysis of the diapause reaction norm revealed significant heritabilities as well as correlations with other traits that could be related to common physiological mechanisms.