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Linking Energetics And Overwintering In Temperate Insects., Brent J Sinclair
Linking Energetics And Overwintering In Temperate Insects., Brent J Sinclair
Biology Publications
Overwintering insects cannot feed, and energy they take into winter must therefore fuel energy demands during autumn, overwintering, warm periods prior to resumption of development in spring, and subsequent activity. Insects primarily consume lipids during winter, but may also use carbohydrate and proteins as fuel. Because they are ectotherms, the metabolic rate of insects is temperature-dependent, and the curvilinear nature of the metabolic rate-temperature relationship means that warm temperatures are disproportionately important to overwinter energy use. This energy use may be reduced physiologically, by reducing the slope or elevation of the metabolic rate-temperature relationship, or because of threshold changes, such …
An Invitation To Measure Insect Cold Tolerance: Methods, Approaches, And Workflow., Brent J Sinclair, Litza E Coello Alvarado, Laura V Ferguson
An Invitation To Measure Insect Cold Tolerance: Methods, Approaches, And Workflow., Brent J Sinclair, Litza E Coello Alvarado, Laura V Ferguson
Biology Publications
Insect performance is limited by the temperature of the environment, and in temperate, polar, and alpine regions, the majority of insects must face the challenge of exposure to low temperatures. The physiological response to cold exposure shapes the ability of insects to survive and thrive in these environments, and can be measured, without great technical difficulty, for both basic and applied research. For example, understanding insect cold tolerance allows us to predict the establishment and spread of insect pests and biological control agents. Additionally, the discipline provides the tools for drawing physiological comparisons among groups in wider studies that may …
Sex Allocation And The Emergence Of Helping In Cooperatively Breeding Species., Josh D Dunn, Teodora Vujicic, Geoff Wild
Sex Allocation And The Emergence Of Helping In Cooperatively Breeding Species., Josh D Dunn, Teodora Vujicic, Geoff Wild
Applied Mathematics Publications
In cooperative breeding systems individuals invest in the reproductive success of others. In this paper, we study the emergence of cooperative breeding systems in which reproductively active breeders receive investment from reproductively non-active helpers. Our goal is to understand how the division of an investment between male and female components of breeder fitness (i.e. the helper sex-allocation strategy) influences the emergence of cooperative breeding itself. Using mathematical models, we arrive at expressions for the inclusive-fitness advantage of helpful behaviour that generalize previous work. These expressions assume an ecologically stable environment, and that breeders make evolutionarily stable sex-allocation decisions. We find …
Positional Differences In Reactive Hyperemia Provide Insight Into Initial Phase Of Exercise Hyperemia., Jeffrey L Jasperse, J Kevin Shoemaker, Eric J Gray, Philip S Clifford
Positional Differences In Reactive Hyperemia Provide Insight Into Initial Phase Of Exercise Hyperemia., Jeffrey L Jasperse, J Kevin Shoemaker, Eric J Gray, Philip S Clifford
Kinesiology Publications
Studies have reported a greater blood flow response to muscle contractions when the limb is below the heart compared with above the heart, and these results have been interpreted as evidence for a skeletal muscle pump contribution to exercise hyperemia. If limb position affects the blood flow response to other vascular challenges such as reactive hyperemia, this interpretation may not be correct. We hypothesized that the magnitude of reactive hyperemia would be greater with the limb below the heart. Brachial artery blood flow (Doppler ultrasound) and blood pressure (finger-cuff plethysmography) were measured in 10 healthy volunteers. Subjects lay supine with …
Contrasting Styles In Cognition And Behaviour In Bumblebees And Honeybees., David F Sherry, Caroline G Strang
Contrasting Styles In Cognition And Behaviour In Bumblebees And Honeybees., David F Sherry, Caroline G Strang
Psychology Publications
Bumblebees and honeybees have been the subjects of a great deal of recent research in animal cognition. Many of the major topics in cognition, including memory, attention, concept learning, numerosity, spatial cognition, timing, social learning, and metacognition have been examined in bumblebees, honeybees, or both. Although bumblebees and honeybees are very closely related, they also differ in important ways, including social organization, development, and foraging behaviour. We examine whether differences between bumblebees and honeybees in cognitive processes are related to differences in their natural history and behaviour. There are differences in some cognitive traits, such as serial reversal learning and …
Insects In Fluctuating Thermal Environments., Hervé Colinet, Brent J Sinclair, Philippe Vernon, David Renault
Insects In Fluctuating Thermal Environments., Hervé Colinet, Brent J Sinclair, Philippe Vernon, David Renault
Biology Publications
All climate change scenarios predict an increase in both global temperature means and the magnitude of seasonal and diel temperature variation. The nonlinear relationship between temperature and biological processes means that fluctuating temperatures lead to physiological, life history, and ecological consequences for ectothermic insects that diverge from those predicted from constant temperatures. Fluctuating temperatures that remain within permissive temperature ranges generally improve performance. By contrast, those which extend to stressful temperatures may have either positive impacts, allowing repair of damage accrued during exposure to thermal extremes, or negative impacts from cumulative damage during successive exposures. We discuss the mechanisms underlying …