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This chapter describes a small but unbiased sample of evolutionary changes: three evolutionary host shifts undertaken by a single butterfly species, Edith's checkerspot, Euphydryas editha. The first host shift is a straightforward and clearly anthropogenic event at Schneider's Meadow (Carson City, Nevada) triggered by the introduction of an exotic species. The second, at Rabbit Meadow (Sequoia National Forest, California) is also anthropogenic but less obviously so, since it is caused by changes in the quality and distribution of native plants. The third host shift, at Sonora Junction in California, is a natural one, in which a natural population extinction and recolonization drove an expansion of diet breadth when a previously rejected host was incorporated into the diet. These observations of host shifts were made by repeatedly censusing naturally laid eggs and larvae of E. editha at more than fifty sites. The chapter also examines the mechanics of evolution of oviposition preference at Rabbit Meadow, speed of evolution and diversity of preference, types of anthropogenic effect, and cryptically anthropogenic effects.

This chapter outlines three basic ways in which humans can alter evolution on adaptive landscapes: through changes in topography, changes in dimensionality, and phenotypic excursions. Changes in topography involve the numbers, positions, gradients, and elevations of surface features on the landscape, such as peaks and valleys. Changes in dimensionality involve the number of at least partially independent traits under selection. Excursions typically involve more or less abrupt changes in the phenotypic position of populations on existing adaptive landscapes, such as through plasticity, hybridization, or genetic manipulation. These different types of change can generate predictions for changes in selection and alterations in evolution — assuming the population can persist through the disturbance. Invasive species can have all of these classes of effects, either for the invasive species or for native species. Climate change will most obviously involve a shift in peak position, such as breeding times under warmer temperatures. Hunting/harvesting will also often involve a shift in peak position, particularly toward smaller and slower growing individuals, and might also decrease phenotypic variance. Habitat loss and fragmentation will influence numbers and positions of adaptive peaks, and can also influence excursions by altering patterns of gene flow in meta-populations. Finally, a decrease in habitat quality can decrease the heights of fitness peaks and cause adaptive landscapes to become smoother. It can also change dimensionality, such as through the introduction of a new contaminant. In conclusion, viewing human-induced environmental change in the framework of changes to adaptive landscapes offers new insights and new perspectives for research.

This chapter sums up the key findings of this study of maternal effects in mammals. It suggests that maternal effects occur when a mother's phenotype influences her offspring's phenotype independent of the genes it inherits from its mother and that these effects can arise before or after birth and can be mediated by the mother's nutrition, physiology, behavior, social status, physical environment, or some combination of these variables. This chapter also proposes long-term studies of wild mammals to better understand variation in maternal effects within individuals across reproductive events as a function of climatic variables, anthropogenic effects, demographic shifts, or senescence.

Smog-choked cities, cancer villages, and contaminated food have become iconic problems of a modernizing China—the tragic, perhaps unavoidable, side effects of a voracious economy. Chapter 3 examines how the sperm bank—jingziku—in China has emerged quite literally as a sanctuary of vitality amid concerns around food safety, air and water pollution, rising infertility, and declining population quality. As a twist on Margaret Lock’s concept of “local biologies,” the chapter argues that exposed biologies have become a matter of concern in China in ways that have corroborated a place for high-tech sperm banks within China’s restrictive reproductive complex. Exposed biologies are a side effect of modernization processes, as industrially manufactured chemicals are increasingly held culpable for a range of pathologies, from cancers andmetabolic diseases to disorders of sex development and infertility.

This chapter discusses the anthropogenic effects on water quality and benthic habitats that negatively affect giant kelp growth and reproduction. These include activities that increase sedimentation, reduce light, and increase turbidity and temperature, causing the decline of Macrocystis. The most important effects of sewer effluent are on microscopic stages and small juvenile sporophytes whose survival and reproduction is inhibited by light reduction, scour, and burial as well as by toxic materials sorbed to particulate organic matter. Excess nutrients that reduce benthic light by stimulating phytoplankton growth may also encourage the growth of algal turfs that directly and indirectly inhibit recruitment of kelp and various large fucoids. Turf-sediment matrices have also been implicated in preventing recolonization of native algal species in Tasmania kelp communities. Ammonia can be toxic, and domestic sewage can contain toxic metals and organic compounds that may be increased if the discharge also contains industrial wastes.