Evolution, 4th Edition

NATuRAl SElECTioN ANd AdAPTATioN 59 with the largest horns has resulted in the evolution of smaller horns (FIGURE 3.5B). In both ...

60 CHAPTER 3 Among several slightly different definitions of natural selection used by biologists today [12], we use this one: n ...

NATuRAl SElECTioN ANd AdAPTATioN 61 the “entities” that differ in survival and reproduction in most discourse about evo- lution ...

62 CHAPTER 3 trees in a forest is important for many tree-nesting birds such as orioles, but almost irrelevant for ground-nestin ...

NATuRAl SElECTioN ANd AdAPTATioN 63 An example of a selfish genetic element that exhibits segregation distortion is the t locus ...

64 CHAPTER 3 Selection of organisms and groups Do oysters have a high reproductive rate “to ensure the survival of the species,” ...

Species selection Selection among groups of organisms is called species selection when the groups involved are species and there ...

66 CHAPTER 3 The Nature of Adaptations Adaptation is a central concept in biology. The word has two related meanings. “Adaptatio ...

NATuRAl SElECTioN ANd AdAPTATioN 67 that enhance swimming but cannot support flight in air (FIGURE 3.13B). Exaptation is a very ...

68 CHAPTER 3 Second, the trait may have evolved by other mechanisms (such as random genetic drift) rather than by natural select ...

NATuRAl SElECTioN ANd AdAPTATioN 69 locomotion or defense) in a way that is likely to increase fitness, relative to indi- vidual ...

70 CHAPTER 3 predators in many families commonly have a streamlined shape, a forked tail fin, and a slender tail base (caudal pe ...

NATuRAl SElECTioN ANd AdAPTATioN 71 predictions made by evolutionary theory, like those in many other scientific disciplines, ar ...

72 CHAPTER 3 a fixed amount of available energy or nutrients, a plant species might evolve higher seed numbers, but only by redu ...

NATuRAl SElECTioN ANd AdAPTATioN 73 if different closely related species coexist, those individuals that use different resources ...

74 CHAPTER 3 What Not To Expect of Natural Selection Selection at the level of genes and individual organisms is inherently “sel ...

■■A feature is an adaptation for a particular func- tion if it has evolved by natural selection for that function by enhancing t ...

SuGGESTioNS FoR FuRTHER REAdiNG Adaptation and Natural Selection by G. C. Wil- liams (Princeton university Press, Princeton, NJ, ...

UNIT II How Evolution Works 04_EVOL4E_CH04.indd 77 3/23/17 8:55 AM ...

04_EVOL4E_CH04.indd 78 3/23/17 8:55 AM ...