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This chapter reviews the genetic consequences of environmental change. These changes are often so rapid that contemporary populations are often not found in genetic equilibrium. Furthermore, human-induced habitat fragmentation often results in a complex mosaic of remaining populations that differ in size and connectivity. A number of tools have been developed to detect population structure, gene flow, and evolution in such complex situations. The chapter provides evidence of rapid evolutionary responses in many organisms to changes in the environment. Such changes may be induced by a multitude of factors, including habitat loss and fragmentation, hindrances to dispersal and hence gene flow, climatic changes, and introduction of invasive species.

Range expansions, biological invasions, and disease spread are all inherently spatial processes that involve the successful introduction or colonization, establishment, and dispersal of organisms (or their propagules) into new areas. Population spatial spread thus involves the interaction of both dispersal and demography with landscape structure. This chapter begins by exploring landscape effects on species’ range shifts and the extent to which species can shift their distributions in response to future land-use and climate-change scenarios. Next, the chapter evaluates the effect that landscape structure might have on invasive spread, including an overview of spatial models that are used to predict whether, when, and how fast an invasive species is likely to spread. The chapter concludes with a discussion of disease spread in a landscape context (landscape epidemiology), which involves the study of how pathogens, vectors, and hosts interact with environmental heterogeneity to influence the incidence and persistence of disease in an area.

Species’ distributions, population sizes, and community composition are affected, directly and indirectly, by climatic changes, leading to changes in location, extent, and/or quality of distributions, range fragmentation or coalescence, and temporal discontinuities in suitable conditions. Quaternary fossil records document these responses, emphasizing individualism of species’ responses and impermanence of communities. Recent observations document similar changes attributable to recent climatic changes, including rapid decreases and increases in ranges and/or populations. Both also document extinctions associated with rapid climatic changes. Modelling studies predict substantial changes in species’ distributions, population sizes, and communities in response to future climatic changes. Implicit assumptions that genetic variation enabling adaptation is ubiquitous throughout species’ ranges, or that gene flow may be sufficiently rapid to allow adaptation, may be invalid. Work is needed to investigate spatial structuring of adaptive genetic variation and rates of gene flow, and to develop new models. Without this, species extinction risks may be severely underestimated.

This chapter focuses on how models of dispersal can improve our understanding, prediction, and management of species' range shifts under environmental change. Most models of species distribution and spread represent dispersal quite crudely; this chapter begins with some thoughts on how these might be integrated with more sophisticated models of dispersal. The importance of inter-individual variability in dispersal and the role that dispersal evolution may play in range shifting is considered. An example of evolutionary entrapment that arises when species expand their ranges over fragmented landscapes is then presented. Finally, potential management strategies that may be used to promote range shifting are considered.

From glaciers melting in Glacier National Park to corals bleaching in Virgin Islands National Park, field research in US National Parks has detected statistically significant changes that analyses of possible causes have attributed to human-induced climate change. Research that has used data from US National Parks shows that climate change has also raised sea level, shifted vegetation and animal ranges, increased tree mortality, and caused other impacts. Average annual temperature of the US National Park System increased at a statistically significant rate of 0.9 ± 0.2ºC per century (mean ± SE) from 1895 to 2010. If we do not reduce greenhouse gas emissions from power plants, cars, and deforestation, temperature in the 21st century could increase at two to six times the rate of 20th century warming, and temporal and spatial patterns of precipitation could change substantially. Analyses of vulnerabilities of resources in US National Parks indicate that continued climate change could fundamentally alter many of the globally unique ecosystems, endangered plant and animal species, and physical and cultural resources that national parks protect.

Rapid and intensifying impacts of climate change are having profound influences on bird populations worldwide, altering their exposure and vulnerability to diverse parasites of conservation or public health concern. This chapter highlights theory and assesses empirical evidence for how climate change will affect avian host–parasite interactions through multiscale processes that jointly determine transmission potential. Shifts in the distribution and phenology of bird populations shape the diversity of parasites they encounter, while behavioral and physiological responses influence individuals’ susceptibility to infection. Additionally, direct and often non-linear effects of abiotic conditions on parasite stages in arthropod vectors or the external environment can be crucial determinants of avian exposure risk. This chapter underscores the necessity of quantifying responses to environmental change in both birds and their parasites and highlights key knowledge gaps and priorities for future research, in order to improve predictions of when climate change will intensify or reduce avian–parasite interactions.

Studies of the timing (phenology) of bird migration provided some of the first evidence for the effects of climate change on organisms. Since the rate of climate change is uneven across the globe, with northern latitudes experiencing faster warming trends than tropical areas, animals moving across latitudes are subject to diverging trends of climate change at different stages of their annual life cycle, and, consequently, they can become mistimed with the local ecological conditions, with potentially negative effects on population size. This chapter reviews the modifications induced by climate change in different migration traits, like the timing of migration events, the distribution of organisms, and the direction and the speed of movements. It also considers the effects of ecological carry-over effects and migratory connectivity on the response of birds to climate change.

Climatic change likely will exacerbate current threats to carnivorous plants. However, estimating the severity of climatic change is challenged by the unique ecology of carnivorous plants, including habitat specialization, dispersal limitation, small ranges, and small population sizes. We discuss and apply methods for modeling species distributions to overcome these challenges and quantify the vulnerability of carnivorous plants to rapid climatic change. Results suggest that climatic change will reduce habitat suitability for most carnivorous plants. Models also project increases in habitat suitability for many species, but the extent to which these increases may offset habitat losses will depend on whether individuals can disperse to and establish in newly suitable habitats outside of their current distribution. Reducing existing stressors and protecting habitats where numerous carnivorous plant species occur may ameliorate impacts of climatic change on this unique group of plants.

In a Kerr liquid consisting of optically anisotropic molecules, the intense pump light may force these molecules to reorientate along the light polarization direction. This is the optical reorientational Kerr effect that is accompanied by a red-shifted light scattering process: part of the incident photon energy is transferred to the molecule to overcome the rotational viscosity of the liquid, while the molecule emits a red-shifted scattering photon. The red-shift value is determined by the induced orientation-angle change or equivalently by the reorientation work done by the scattering molecule. When the pump intensity is above a certain threshold, such a process may lead to stimulated Kerr scattering (SKS). As the induced orientation angle changes for different molecules may be different depending on their initial orientation angle, the observed stimulated scattering red shift may cover a super-broad spectral range (up to 300–500 cm⁻¹).