Evolution, 4th Edition

EVoluTioN iN SPACE 199 from comparisons between the tolerance of plants grown from seeds and of adult plants (see Figure 8.3). O ...

200 CHAPTER 8 A very different outcome occurs when migration onto an island is much stron- ger than selection (s << m). Th ...

EVoluTioN iN SPACE 201 Equation 8.4 shows that the width of a cline can be used to estimate the strength of selection. Alleles f ...

202 CHAPTER 8 Some kinds of chromosomal rearrangements are underdominant (see Chapter 5). Consider what happens if two populatio ...

EVoluTioN iN SPACE 203 genetically very similar. In short, for a selectively neutral locus, a single migrant per generation is s ...

204 CHAPTER 8 the phenotypic and genomic levels. In humans, the E PA S1 locus, which contributes to adaptation to high elevation ...

EVoluTioN iN SPACE 205 Dispersing individuals experience less competition than their siblings that stay at home. Genes for dispe ...

206 CHAPTER 8 meadow appears, for example after a fire, it is colonized by butterflies that disperse from neighboring patches. T ...

EVoluTioN iN SPACE 207 The evolution of dispersal rates and distances has a host of downstream effects. Dispersers take their ge ...

208 CHAPTER 8 centers [6, 26]. Thus, many species are tracking their niche by shifting where they live, as the environment to wh ...

■■Most species show geographic variation in allele frequencies and the means of phenotypic traits. Clines, which are smooth chan ...

B. Charlesworth and colleagues review the ef- fects of gene flow and other evolutionary forces on patterns of neutral variation ...

provide information about rates of migration among populations. SNPs that show unusual patterns of genetic variation may indicat ...

09_EVOL4E_CH09.indd 212 3/23/17 9:36 AM ...

In the Rift Valley of eastern Africa, just south of the equator, lie three great lakes and many smaller ones. Lakes Tanganyika a ...

214 CHAPTER 9 What caused this explosion of diversity? Do the number and ecological variety of species depend only on current ec ...

SPECiES And SPECiATion 215 What Are Species? Several definitions of “species”—which is Latin for “kind”—are used by biolo- gists ...

216 CHAPTER 9 interbreeding where they meet. The BSC also rec- ognizes cases of “sibling species” (such as the gray forms of the ...

SPECiES And SPECiATion 217 These and other considerations have inspired several alternative species defi- nitions. Some systemat ...

218 CHAPTER 9 occasionally, among sympatric species in many groups of plants and animals [51], and genes are sometimes incorpora ...