It is generally accepted that taxa exhibit genetic variation in phenotypic plasticity, but many questions remain unan- swered about how divergent plastic responses evolve under dissimilar ecological conditions. Hormon...It is generally accepted that taxa exhibit genetic variation in phenotypic plasticity, but many questions remain unan- swered about how divergent plastic responses evolve under dissimilar ecological conditions. Hormones are signaling molecules that act as proximate mediators of phenotype expression by regulating a variety of cellular, physiological, and behavioral re- sponses. Hormones not only change cellular and physiological states but also influence gene expression directly or indirectly, thereby linking environmental conditions to phenotypic development. Studying how hormonal pathways respond to environ- mental variation and how those responses differ between individuals, populations, and species can expand our understanding of the evolution of phenotypic plasticity. Here, we explore the ways that the study of hormone signaling is providing new insights into the underlying proximate bases for individual, population or species variation in plasticity. Using several studies as exem- plars, we examine how a ＇norm of reaction＇ approach can be used in investigations of hormone-mediated plasticity to inform the following： 1） how environmental cues affect the component hormones, receptors and enzymes that comprise any endocrine sig- naling pathway, 2） how genetic and epigenetic variation in endocrine-associated genes can generate variation in plasticity among these diverse components, and 3） how phenotypes mediated by the same hormone can be coupled and decoupled via independent plastic responses of signaling components across target tissues. Future studies that apply approaches such as reaction norms and network modeling to questions concerning how hormones link environmental stimuli to ecologically-relevant phenotypic re- sponses should help unravel how phenotypic plasticity evolves展开更多
Global climate change is impacting organisms, biological communities and ecosystems around the world. While most research has focused on characterizing how the climate is changing, including modeling future climatic c...Global climate change is impacting organisms, biological communities and ecosystems around the world. While most research has focused on characterizing how the climate is changing, including modeling future climatic conditions and predicting the impacts of these conditions on biodiversity, it is also the case that climate change is altering the environmental impacts of chemical pollution. Future climate conditions are expected to influence both the worldwide distribution of chemicals and the toxi- cological consequences of chemical exposures to organisms. Many of the environmental changes associated with a warming global climate （e.g., increased average - and possibly extreme - temperatures; intense periods of drier and wetter conditions; reduced ocean pH; altered salinity dynamics in estuaries） have the potential to enhance organism susceptibility to chemical toxicity. Addi- tionally, chemical exposures themselves may impair the ability of organisms to cope with the changing environmental conditions of the shifting climate. Such reciprocity in the interactions between climate change and chemicals illustrates the complexity inherent in predicting the toxicological consequences of chemical exposures under future climate scenarios. Here, we summarize what is currently known about the potential reciprocal effects of climate change and chemical toxicity on wildlife, and depict current approaches and ongoing challenges for incorporating climate effects into chemical testing and assessment. Given the rapid pace of new man-made chemistries, the development of accurate and rapid methods to evaluate multiple chemical and non-chemical stressors in an ecologically relevant context will be critical to understanding toxic and endocrine-disrupting effects of chemical pollutants under future climate scenarios [Current Zoology 61 （4）： 669-689, 2015].展开更多
Humans and wildlife are exposed to an ever-increasing array of man-made chemicals that are now meas-ured in every habitat on our planet from the Earth＇s highest mountain peaks to sediments in the deep ocean （e.g., F...Humans and wildlife are exposed to an ever-increasing array of man-made chemicals that are now meas-ured in every habitat on our planet from the Earth＇s highest mountain peaks to sediments in the deep ocean （e.g., Farrington and Takada, 2014; Quiroz et al., 2009; Veron et al., 1987; Villa et al., 2006）. In addition to the expanding variety of synthetic chemistries in use, there are many substances that are components of the Earth that may through human activities concentrate at high- levels or be released into the environment in forms that enhance their bioavailability, exposure, and toxicity potential.展开更多
文摘It is generally accepted that taxa exhibit genetic variation in phenotypic plasticity, but many questions remain unan- swered about how divergent plastic responses evolve under dissimilar ecological conditions. Hormones are signaling molecules that act as proximate mediators of phenotype expression by regulating a variety of cellular, physiological, and behavioral re- sponses. Hormones not only change cellular and physiological states but also influence gene expression directly or indirectly, thereby linking environmental conditions to phenotypic development. Studying how hormonal pathways respond to environ- mental variation and how those responses differ between individuals, populations, and species can expand our understanding of the evolution of phenotypic plasticity. Here, we explore the ways that the study of hormone signaling is providing new insights into the underlying proximate bases for individual, population or species variation in plasticity. Using several studies as exem- plars, we examine how a ＇norm of reaction＇ approach can be used in investigations of hormone-mediated plasticity to inform the following： 1） how environmental cues affect the component hormones, receptors and enzymes that comprise any endocrine sig- naling pathway, 2） how genetic and epigenetic variation in endocrine-associated genes can generate variation in plasticity among these diverse components, and 3） how phenotypes mediated by the same hormone can be coupled and decoupled via independent plastic responses of signaling components across target tissues. Future studies that apply approaches such as reaction norms and network modeling to questions concerning how hormones link environmental stimuli to ecologically-relevant phenotypic re- sponses should help unravel how phenotypic plasticity evolves
文摘Global climate change is impacting organisms, biological communities and ecosystems around the world. While most research has focused on characterizing how the climate is changing, including modeling future climatic conditions and predicting the impacts of these conditions on biodiversity, it is also the case that climate change is altering the environmental impacts of chemical pollution. Future climate conditions are expected to influence both the worldwide distribution of chemicals and the toxi- cological consequences of chemical exposures to organisms. Many of the environmental changes associated with a warming global climate （e.g., increased average - and possibly extreme - temperatures; intense periods of drier and wetter conditions; reduced ocean pH; altered salinity dynamics in estuaries） have the potential to enhance organism susceptibility to chemical toxicity. Addi- tionally, chemical exposures themselves may impair the ability of organisms to cope with the changing environmental conditions of the shifting climate. Such reciprocity in the interactions between climate change and chemicals illustrates the complexity inherent in predicting the toxicological consequences of chemical exposures under future climate scenarios. Here, we summarize what is currently known about the potential reciprocal effects of climate change and chemical toxicity on wildlife, and depict current approaches and ongoing challenges for incorporating climate effects into chemical testing and assessment. Given the rapid pace of new man-made chemistries, the development of accurate and rapid methods to evaluate multiple chemical and non-chemical stressors in an ecologically relevant context will be critical to understanding toxic and endocrine-disrupting effects of chemical pollutants under future climate scenarios [Current Zoology 61 （4）： 669-689, 2015].
文摘Humans and wildlife are exposed to an ever-increasing array of man-made chemicals that are now meas-ured in every habitat on our planet from the Earth＇s highest mountain peaks to sediments in the deep ocean （e.g., Farrington and Takada, 2014; Quiroz et al., 2009; Veron et al., 1987; Villa et al., 2006）. In addition to the expanding variety of synthetic chemistries in use, there are many substances that are components of the Earth that may through human activities concentrate at high- levels or be released into the environment in forms that enhance their bioavailability, exposure, and toxicity potential.
