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Biology Publications

2016

Animals

Articles 1 - 5 of 5

Full-Text Articles in Life Sciences

Can We Predict Ectotherm Responses To Climate Change Using Thermal Performance Curves And Body Temperatures?, Brent J Sinclair, Katie E Marshall, Mary A Sewell, Danielle L Levesque, Christopher S Willett, Stine Slotsbo, Yunwei Dong, Christopher D G Harley, David J Marshall, Brian S Helmuth, Raymond B Huey Nov 2016

Can We Predict Ectotherm Responses To Climate Change Using Thermal Performance Curves And Body Temperatures?, Brent J Sinclair, Katie E Marshall, Mary A Sewell, Danielle L Levesque, Christopher S Willett, Stine Slotsbo, Yunwei Dong, Christopher D G Harley, David J Marshall, Brian S Helmuth, Raymond B Huey

Biology Publications

Thermal performance curves (TPCs), which quantify how an ectotherm's body temperature (Tb ) affects its performance or fitness, are often used in an attempt to predict organismal responses to climate change. Here, we examine the key - but often biologically unreasonable - assumptions underlying this approach; for example, that physiology and thermal regimes are invariant over ontogeny, space and time, and also that TPCs are independent of previously experienced Tb. We show how a critical consideration of these assumptions can lead to biologically useful hypotheses and experimental designs. For example, rather than assuming that TPCs are fixed during ontogeny, one …


Reproductive Arrest And Stress Resistance In Winter-Acclimated Drosophila Suzukii., Jantina Toxopeus, Ruth Jakobs, Laura V Ferguson, Tara D Gariepy, Brent J Sinclair Jun 2016

Reproductive Arrest And Stress Resistance In Winter-Acclimated Drosophila Suzukii., Jantina Toxopeus, Ruth Jakobs, Laura V Ferguson, Tara D Gariepy, Brent J Sinclair

Biology Publications

Overwintering insects must survive the multiple-stress environment of winter, which includes low temperatures, reduced food and water availability, and cold-active pathogens. Many insects overwinter in diapause, a developmental arrest associated with high stress tolerance. Drosophila suzukii (Diptera: Drosophilidae), spotted wing drosophila, is an invasive agricultural pest worldwide. Its ability to overwinter and therefore establish in temperate regions could have severe implications for fruit crop industries. We demonstrate here that laboratory populations of Canadian D. suzukii larvae reared under short-day, low temperature, conditions develop into dark 'winter morph' adults similar to those reported globally from field captures, and observed by us …


Paradoxical Acclimation Responses In The Thermal Performance Of Insect Immunity., Laura V Ferguson, David E Heinrichs, Brent J Sinclair May 2016

Paradoxical Acclimation Responses In The Thermal Performance Of Insect Immunity., Laura V Ferguson, David E Heinrichs, Brent J Sinclair

Biology Publications

Winter is accompanied by multiple stressors, and the interactions between cold and pathogen stress potentially determine the overwintering success of insects. Thus, it is necessary to explore the thermal performance of the insect immune system. We cold-acclimated spring field crickets, Gryllus veletis, to 6 °C for 7 days and measured the thermal performance of potential (lysozyme and phenoloxidase activity) and realised (bacterial clearance and melanisation) immune responses. Cold acclimation decreased the critical thermal minimum from -0.5 ± 0.25 to -2.1 ± 0.18 °C, and chill coma recovery time after 72 h at -2 °C from 16.8 ± 4.9 to 5.2 …


Paradoxical Acclimation Responses In The Thermal Performance Of Insect Immunity., Laura V Ferguson, David E Heinrichs, Brent J Sinclair May 2016

Paradoxical Acclimation Responses In The Thermal Performance Of Insect Immunity., Laura V Ferguson, David E Heinrichs, Brent J Sinclair

Biology Publications

Winter is accompanied by multiple stressors, and the interactions between cold and pathogen stress potentially determine the overwintering success of insects. Thus, it is necessary to explore the thermal performance of the insect immune system. We cold-acclimated spring field crickets, Gryllus veletis, to 6 °C for 7 days and measured the thermal performance of potential (lysozyme and phenoloxidase activity) and realised (bacterial clearance and melanisation) immune responses. Cold acclimation decreased the critical thermal minimum from -0.5 ± 0.25 to -2.1 ± 0.18 °C, and chill coma recovery time after 72 h at -2 °C from 16.8 ± 4.9 to 5.2 …


Similar Metabolic Rate-Temperature Relationships After Acclimation At Constant And Fluctuating Temperatures In Caterpillars Of A Sub-Antarctic Moth., Steven L Chown, Tanya M Haupt, Brent J Sinclair Feb 2016

Similar Metabolic Rate-Temperature Relationships After Acclimation At Constant And Fluctuating Temperatures In Caterpillars Of A Sub-Antarctic Moth., Steven L Chown, Tanya M Haupt, Brent J Sinclair

Biology Publications

Temperature compensation in whole-animal metabolic rate is one of the responses thought, controversially, to characterize insects from low temperature environments. Temperature compensation may either involve a change in absolute values of metabolic rates or a change in the slope of the metabolic rate - temperature relationship. Moreover, assessments of compensation may be complicated by animal responses to fluctuating temperatures. Here we examined whole animal metabolic rates, at 0 °C, 5 °C, 10 °C and 15 °C, in caterpillars of the sub-Antarctic moth, Pringleophaga marioni Viette (Tineidae), following one week acclimations to 5 °C, 10 °C and 15 °C, and fluctuating …