Adaptive Radiation

"groups of closely related organisms that have evolved morphological and behavioral features enabling them to exploit different ecological niches" - Fleagle, Primate Adaptation and Evolution, 2nd Ed.

"the evolutionary diversification of a single lineage into a variety of species with different adaptive properties" - Grant, Ecology and Evolution of Darwin's Finches, 1999.

"great development of minor types in the new adaptive zone" - Mayr, Animal Species and Evolution

"'bursts' of divergence of many lineages during a short period" - Futuyma, Evolutionary Biology, 2nd Ed.

"More or less simultaneous divergence of numerous lines all from much the same ancestral adaptive type into different, also diverging adaptive zones" -Simpson, Major Features of Evolution, 1953

"An episode of significantly sustained excess of cladogenesis over extinction, with adaptive divergence cued by the appearance of some form of ecological stimulus" -Skelton, P. W., 1993. Adaptive radiation: definition and diagnostic tests. pp. 45-58 in Evolutionary patterns and processes, D. R. Lees and D. Edwards, eds. London, England: Academic Press.

"it is a well-known principle of zoological evolution that an isolated region, if large and sufficiently varied in its topography, soil, climate and vegetation, will give rise to a diversified fauna according to the law of adaptive radiation from primitive and central types. Branches will spring off in all directions to take advantage of every possible opportunity of securing food. The modifications which animals undergo in this adaptive radiation are largely of mechanical nature, they are limited in number and kind by hereditary, stirp or germinal influences, and thus result in the independent evolution of similar types in widely-separated regions under the law of parallelism or homoplasy.
This law causes the independent origin not only of similar genera but of similar families and even of our similar orders. Nature thus repeats herself upon a vast scale, but the similarity is never complete and exact." - Osborn, 1900. "The geological and faunal relations of Europe and America during the tertiary period and the theory of the successive invasions of an African fauna." Science 11 (276), 561–574.

"One definition of adaptive radiation is that some organisms have features that allow them to separate more prolifically or become extinct less frequently than organisms without these features" - Guyer and Slowinski 2003. "Adaptive radiation and the topology of large phy-
logenies." Evolution 47 (1), 253–263.

"the evolution of a diversity of ecological roles and attendant adaptations in different species within a lineage" - Givnish 1997. Adaptive radiation and molecular systematics: issues and approaches. In Molecular Evolution and Adaptive Radiation.

"the term ‘adaptive radiation’ should be reserved for those clades that are exceptionally diverse in terms of the range of habitats occupied and attendant morphological adaptations" - Losos, J. B. and D. B. Miles (2002). Testing the hypothesis that a clade has adaptively radiated: Iguanid lizard clades as a case study. The American Naturalist 160 (2), 147–157.

"the diversification of a lineage into species that exploit a variety of different resource types and that differ in the morphological or physiological traits used to exploit those resources'' -Schluter, D. (1996). Ecological causes of adaptive radiation. The American Naturalist 148, S40–S64.

"the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage" -Gavrilets, S. and A. Vose (2005). Dynamic patterns of adaptive radiation. PNAS 102 (50), 18040-18045.

"'Adaptive radiation' refers to those evolutionary groups that have exhibited an exceptional extent of adaptive diversification into a variety of ecological niches'' -Gavrilets, S. and J. B. Losos (2009). Adaptive radiation: Contrasting theory with data. Science 323 (5915), 732–737.

"the rapid evolution from a common ancestor of several species that occupy different ecological niches" -Grant, P. R. and B. R. Grant (2007). How and Why Species Multiply: The Radiation of Darwin’s Finches. Princeton University Press.

"the rapid diversification of an ancestral population into several ecologically different species, associated with
adaptive morphological or physiological divergence" -Seehausen, O. (2004). Hybridization and adaptive radiation. Trends in Ecology & Evolution 19 (4), 198–207.