Radiation adaptive

Baldwin, B. G., Kyhos, D. W. and Dvolrak, J. 1990. Chloroplast DNA evolution and adaptive radiation in the Hawaiian silversword alliance (Asteraceae—Madiinae). Ann. Missouri Bot. Gard. 77 96-109. 

Witter, M. S. and Carr, G. D. 1988. Adaptive radiation and genetic differentiahon in the Hawaiian silversword alliance (Compositae Madhnae). Evolution 42 1278-1287. 

Jaksic, F. M., Nunez, H. and Ojeda, F. P. (1980) Body proportions, microhabitat selection, and adaptive radiation of Liolaemus lizards in central Chile. Oecologia 45, 178-181. 

Zietara, M.S. and Lumme, J. (2002) Speciation by host switch and adaptive radiation in a fish parasite genus Cyrodactylus (Monogenea, Cyrodactylidae). Evolution 56, 2445-2458. 

Taylor, E.R., and J.D. McPhail (1999). Evolutionary history of an adaptive radiation in species pairs of threespine sticklebacks (Gasterosteus) insights from mitochondrial DNA. J. Linnean Soc. 66 271-293. 

Paleontology has shown that the history of life has been full of adaptive radiations, processes in which an ancestral taxon gave rise to descendant taxa which diverged by adapting to different environmental conditions. Some adaptive radiations have been explained with the mechanism of phyletic gradualism, while others are better described by punctuated equilibria, but in all cases they are classical processes of adaptation to the environment by natural selection. 

The temptation to declassify the Cambrian explosion, and to assimilate it to processes that can easily be accounted for, is strong, but leads to an unbridgeable contradiction between experimental data and theoretical previsions. The only reasonable conclusion, therefore, is that the Cambrian explosion was not an adaptive radiation, i.e. it was not a simple process of adaptation to the environment, but something very different. 

Such a conclusion is directly suggested by the very characteristics of the explosion. All adaptive radiations that came after the Cambrian have never modified the body plans, while the Cambrian explosion was characterised precisely by modifications of those plans. And, in a similar way, no adaptive radiations have ever changed the phylotypic stage of developing embryos, while the Cambrian explosion did precisely that. 

The message that nature herself appears to be sending us is that the Cambrian explosion was a rare event in the history of life, comparable perhaps only to the origin of life or to the origin of the mind. And what is so special about these rare episodes of macroevolution is the appearance of biological characteristics which have never been changed ever since. The mechanism that we are looking for, in conclusion, must explain precisely why the Cambrian explosion was so different from a normal adaptive radiation, even if this means that we cannot explain it with classical mechanisms. 

Cei, J. M. 1986. Speciation and adaptive radiation in Andean Telmatobius frogs, in F. Vuilleumier and M. Monasterio (eds.) High Altitude Tropical Biogeography. Oxford University Press, New York, pp. 374-386. 

First omit the observed cosmic abundance of the biogenic elements that are favorable to life. Then omit the environments (earth-like planets or Europa-like satellites) that favor evolution and adaptive radiation. The consequence of omitting both factors is that life most likely would not arise. 

Anole lizards from some Caribbean islands (Anolis spp.) provide another example of evolutionary convergence. In Cuba, Hispaniola (shared by Haiti and the Dominican Republic), Jamaica, and Puerto Rico (the so-called Greater Antilles), the observed phenomenon suggests that in similar environments adaptive radiation can overcome historical contingencies to produce strikingly similar evolutionary outcomes. We could even say that replicated adaptive radiation has occurred in the various islands. In fact, it has been... 

Fosos, J. B., Jackman, T. R., Farson, A. et al. (1998). Contingency and determinism in replicated adaptive radiations of island lizards. Science, 279, 2115-18. 

Gillespie, R. (2004). Community assembly through adaptive radiation in Hawaiian spiders. Science, 303, 356-9. 

The RIP active-site stmcture and enzymatic function are similar across diverse phylogeny, including those of bacteria, plants, and fungi. Little is known concerning the adaptive radiation or the evolutionary convergence of this family of enzymes. There are no proven selective advantages... 

In the opinion of Hsiao et al. (1999), the early grasses evolved during the mid-Upper Cretaceous in or near the tropical forests of South America, where they remained in low numbers. Archetypes of all the major subfamilies probably evolved after rapid climate change in the Upper Cretaceous in response to drastic climate change, and adaptive radiation subsequently set subfamilies apart. The Arundinoideae developed in the more seasonal open savannah/semiarid regions, while the Panicoideae and Chlorideae evolved rapidly and developed and adapted... 

DE Vargas, C., Renaud, S., Hilbrecht, H. Pawlowski, J. 2001. Pleistocene adaptive radiation in Globorotalia tnmcatulinoides. genetic, morphologic and environmental evidence. Paleobiology, 27, 104-125. 

Early evolution produced organisms with generalized compounds and metabolic pathways that have had a profound effect on how the earth system operates. With the development of the an-giosperms and the coincident adaptive radiation of animals, novel and diverse chemical compounds have evolved. Many of these compounds have also had impacts on biogeochemistry, in some cases only locally, but in others more generally. 

When a group of organisms share a homologous structure, which is specialized, to perform a variety of functions in order to adapt to different environmental conditions are called adaptive radiation. The gradual spreading of organisms with adaptive radiation is known as divergent evolution. 

Schluter, D. (2000). The Ecology of Adaptive Radiation. Oxford Oxford University Press. 

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