Evolution in human‐altered environments: a summit to translate science into policy

Although evolutionary biologists have long believed that evolution is the single unifying theory of all of the biological sciences, they have neither modestly nor ostentatiously championed the relevance of their science to the greater public. In fact, until relatively recently, evolutionary biologists have been ‘happily disengaged from the practical applications of their field to human affairs’ (Futuyma 1995). However, in the last decade, it has become increasingly apparent that organisms are evolving at palpable timescales and more often than not, in response to environmental perturbations induced by humans (e.g. bacteria in response to antibiotics; insects in response to pesticides). As an increasing number of evolutionary studies document the evolution of organisms to this new form of ‘natural’ selection, the unavoidable evidence that evolutionary biology is indeed highly relevant for practical matters rapidly accumulates. Appropriately, the Institute of the Environment at the University of California, Los Angeles (UCLA), recently hosted ‘Evolutionary Change in Human-Altered Environments: An International Summit to Translate Science into Policy’ (8–10 February 2007). The meeting, organized by Thomas Smith (UCLA, USA) and Louis Bernatchez (Laval University, Canada), featured presentations by prominent international evolutionary biologists as well as by directors and managers of numerous state and national (US) government and environmental organizations. As the name suggests, the aims of the meeting were both to highlight the growing body of research documenting rapid evolutionary responses of organisms to human-mediated changes in the environment, and to facilitate communication between evolutionary biologists and policy makers. The overarching theme of the meeting was the description and quantification of phenotypic and genetic changes resulting from human-altered environments. Examples of such alterations included breeding organisms in captivity, size-selective harvesting, urbanization, global climate change, and accidental introductions of invasive species. Most talks provided evidence for at least a phenotypic response of organisms to these environmental changes, but as was emphasized by separate talks by Juha Merilä (University of Helsinki, Finland) and Andrew Hendry (McGill University, Canada), a greater understanding of whether these phenotypic changes are the result of underlying genetic changes is imperative to better predict the evolutionary trajectories of these organisms. Several talks focused on the effects of climate change. Marcel Visser (The Netherlands Institute of Ecology) emphasized that the response of organisms to climate change will be taxon-specific. For example, phenological responses of prey to increases in temperature are likely to differ from those of predators. Nonsynchronous shifts in phenology may result in the disruption interspecific interactions, which will likely lead to changes in the population dynamics of both predators and prey. William Bradshaw and Christina Holzapfel (University of Oregon, USA) showed that the major effect of climate warming will not be the change in temperature per se, but rather the shift in seasons. Earlier springs, later winters and longer growing seasons will lead to natural selection for altered timing of seasonal events such as reproduction, migration and dormancy. Since animal populations use the length of day to anticipate and prepare for these seasonal events, the major genetic response of animal populations will be to day length and not to tolerance of higher temperatures. Other notable talks from the summit discussed how evolutionary biology can improve conservation efforts. For instance, careful breeding of captive-bred organisms between populations may facilitate the maintenance of genetic variation among all populations and thus improve adaptive potential once re-released into the wild (Phil Hedrick, Arizona State University, USA). And, when restoring human-altered habitats, it is important to realize that wild species may have adapted to the human-altered state. Thus, the adaptation of organisms to human-mediated environmental changes (e.g. life-history shifts of salmon in response to river dams) should be considered when returning the altered habitats to their premodified state (Robin Waples, National Marine Fisheries Service, USA), as organisms will need to re-adapt to these original habitats. The uniqueness of the summit was not only its focus on using evolutionary biology to address questions of applied importance, but also its attempt to facilitate the incorporation of evolutionary biology into environmental policy. Although conservation programs do not typically take into consideration an organism's adaptive potential, the general consensus of policy advisors was that it was time to start. Advisors urged the need for heightened communication between government, environmental organizations and evolutionary biologists, and repeatedly stressed that any recommendation coming from scientists needed to be clear and simple. For example, Mark Reynolds (Nature Conservancy, USA) noted that ‘if you can map it, you can conserve it’, meaning that mapping geographical regions of high genetic diversity could facilitate the protection of these areas. Interestingly, some discussion arose regarding the receptiveness of the general public to incorporating evolution into conservation and environmental policy given the relatively high proportion of individuals (especially in the USA) who still view evolution as a controversial topic. Overall, it was clear from the summit that (i) rapid changes to the environment are propelling evolutionary trajectories of organisms into potentially uncharted territory, and (ii) that conservation and environmental policies need to incorporate methods that maximize genetic variation of organisms in order to facilitate their ability to respond to changes in selection pressures. This summit, which will be featured in an upcoming 2007 Molecular Ecology special issue, coupled with the highly anticipated launch of Blackwell Publishing's newest evolution journal, Evolutionary Applications, underscores the importance of evolutionary biology to human affairs far and wide.

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