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While visiting Galápagos, the young Charles Darwin was confused by the similarity of various finches he observed. We now understand that what we see as different finch species are “species before speciation is complete.” The confusion is inherent: many of them remain similar enough to form fertile hybrids. But a robust difference exists between the groups of ground finches and tree finches, raising the question, what prompted the evolution of that clear distinction? The primary habitats for tree finches are tree species of the wonderful Galápagos daisy genus, Scalesia, that dominate the forests of the humid areas of various islands. Did the evolution of daisies into trees influence the evolution of differences between ground and tree finches? For that matter, how did highland trees evolve from lowland shrubby daisies, thus forming the highland habitat for tree finches? Several lines of evidence, including a contemporary interaction analysis of various birds and trees, suggest that the giant daisies of Galápagos and the tree species of Darwin’s finches coevolved.

This chapter begins with an overview of the virtual pet industry. It describes the rise of the Tamagotchi in the late 1990s and the emergence of online virtual pet sites. It then discusses the development of Palmagotchi (cute Palm)—a simple educational game played occasionally over long periods of time outside of class, connecting back to classroom content through discussion and data analysis. Palmagotchi draws upon analogies to Darwin’s finches in the Galapagos. Players maintain families of birds and islands of flowers while considering issues in genetics, ecology, and evolution to best maximize their chances for survival.

One of the central assumptions in Wright's original conception of the adaptive landscape, was that fitness remained constant through time. Decades of study have since shown that this assumption is invalid. This chapter explores how spatial and temporal variability in selection lead to dynamic shifts in adaptive landscapes. After considering a number of empirical examples of variable selection, it concludes that traits that are particularly important in biotic interactions are more likely to result in shifting landscapes. As such the chapter considers the various roles of frequency- and density dependence, sexual selection, predation, competition, phenotypic plasticity, and genetic polymorphism in affecting the strength and forms of selection. The review here supports a view of adaptive landscapes as highly dynamic and fluctuating.