0198566123.pdf

leaves undamaged ‘islands’ of forest, termed kipukas, which can vary from a few square metres to many hectares in area. Whether ...

ADAPTIVE RADIATION 229 Table 9.3 Endemic (in bold) and non-endemic Macaronesian vascular plant genera represented by 10 or more ...

by abrupt speciation involving hybridization, poly- ploidy, and other forms of sudden chromosomal change. However, it appears th ...

FROM VALLEY ISOLATES TO ISLAND-HOPPING RADIATIONS 231 Box 9.2 The explosive radiation of cichlid fishes in the African Great Lak ...

have favoured the same mutations, resulting in two related taxa of separate (i.e. paraphyletic) origin being incorrectly classif ...

another than is the case for the other archipelagos, so that the spread of newly evolved endemics across the archipelago is hamp ...

scenario needs many more founder events, at least one for each occupied habitat on each island, and would likely involve coloniz ...

However, the Canaries also provide examples where phylogeographical analysis has shown a pat- tern of colonization not predictab ...

●Progressive clades and grades.A clade is an entire group descended from one common ances- tor (i.e. it is monophyletic). Grade ...

●Recent colonization.Where a comparatively recent colonization event has taken place, landfall may have occurred on any of the e ...

dispersal events. Examples include Pelargonium, Wurmbea, and Pentaschistis, each of which has Australian members that are recent ...

OBSERVATIONS ON THE FORCING FACTORS OF ISLAND EVOLUTION 239 past’). In illustration, Silvertown (2004) has argued that genetic d ...

240 EMERGENT MODELS OF ISLAND EVOLUTION exclusive tendency to single-island endemism. Most species thus appear to evolve on an i ...

VARIATION IN INSULAR ENDEMISM BETWEEN TAXA 241 monocots are endemic, and 205 of the 351 dicots are endemic (Porter 1979, 1984). ...

242 EMERGENT MODELS OF ISLAND EVOLUTION Box 9.3 The island immaturity–speciation pulse model of island evolution Emerson and Kol ...

VARIATION IN INSULAR ENDEMISM BETWEEN TAXA 243 out this temporal model, we describe the observations on which it is based, and t ...

244 EMERGENT MODELS OF ISLAND EVOLUTION figure. Further, although both SandImay each decline during the phase of island subsiden ...

exploit the opportunities available, through combi- nations of adapative, non-adaptive and archipel- agic radiation. Yet, still ...

they fit together (as, e.g. Fig. 7.7; Box 9.3). Figure 9.11 is one attempt to place island evolutionary ideas and models into a ...

widely spread archipelagos, speciation is frequent, but often without the greatest radiation of lineages, fitting the model of a ...