What is adaptive radiation?
Adaptive radiation occurs when a species occupies a habitat with unoccupied niches. Specialized adaptations arise relatively quickly in the population as members of the species radiate out into these niches. This process is driven by natural selection and results in new phenotypes and eventually new species may arise. Darwin's finches on the Galapagos Islands are an example of this concept.
Diversification of a group of plants or animals caused by environmental change such as flooding of vast areas around the continents, creating seas depth lacking, is called adaptive radiation, usually being followed by the evolution of a large number of new forms of life, perfectly adapted to the new living environment that surrounds them.
Paleontologists have tried to explain the causes of rapid development, especially during the periods most common of progressive evolution. They found that certain groups of fossils have evolved faster than others.Groups who had the fastest evolution were used for dating fossils. They allow determining the relative age of the zone or layer of rock in which they were found. Dating fossils are characteristic of a single layer of rocks. For example, trilobites fossils, which have been rapidly evolving, are considered fossils dating of Paleozoic era, while Ammonites have the same function for Mesozoic era rocks.
However, some scientists believe that the rate of evolution of certain groups may appear higher than others because they have several characteristics that can vary.
The diversification of a group of organisms into forms filling different ecological niches.
Adaptive radiation occurs when a variety of new forms—including new related species—adapts to and fills a variety of ecological niches. Adaptive radiation has occurred multiple times in evolutionary history. The principles of adaptive radiation are most clearly illustrated by Darwin’s case study of the finches of the Galapagos Islands. Thirteen different varieties of Galapagos finches were noted by Darwin These differed mostly in the shape and size of their beaks, on finch form for each island in the Galapagos chain. Darwin realized that these thirteen varieties had descended from one common ancestor. Each form adapted to local selection pressures during adaptive radiation.