Evolutionary radiation: Difference between revisions

m (wikification)
==Evolutionary radiation in the fossil record==
Much of the work carried out by [[Palaeontology|palaeontologists]] studying evolutionary radiations has been using marine [[invertebrate]] [[fossil]]s simply because these tend to be much more numerous and easy to collect in quantity than large land [[vertebrate]]s such as [[mammal]]s or [[dinosaur]]s. [[Brachiopod]]s, for example, underwent major bursts of evolutionary radiation in the Early [[Cambrian]], Early [[Ordovician]], to a lesser degree throughout the [[Silurian]] and [[Devonian]], and then again during the [[Carboniferous]]. During these periods, different [[species]] of brachiopods independently assumed a similar morphology, and presumably mode of life, to species that had lived millions of years before. This phenomenon, known as [[homeomorphy]] is explained by [[convergent evolution]]: when subjected to similar selective pressures, organisms will often evolve similar adaptations. <ref>''Living and Fossil Brachiopods'' by M. J. S. Rudwick (1970)</ref>. Further examples of rapid evolutionary radiation can be observed among [[ammonite]]s, which suffersuffered a series of extinctions from which they repeatedly re-diversifydiversified; and [[trilobite]]s which, during the Cambrian, rapidly evolved into a variety of forms occupying many of the [[Ecological niche|niche]]s exploited by [[crustacean]]s today <ref>''Aquagenesis, The Origins and Evolution of Life in the Sea'' by Richard Ellis (2001)</ref>, <ref>''Ammonites'' by Neale Monks & Philip Palmer (2002)</ref>, <ref>''Trilobite, Eyewitness to Evolution'' by Richard Fortey (2000)</ref>
==Recent evolutionary radiations==