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Adaptive radiation often occurs when a species is introduced to a new ecosystem, or when a species can survive in an environment that was unreachable before. For example, the Darwin's finches on the Galapagos islands developed from a single species of finches that reached the islands. Other examples include the introduction of predatory mammals to Australia by humans, the development of the first birds, which suddenly were able to expand their territory into the air, or the development of lung fish during the Devonian period, about 300 million years ago.

The dynamics of adaptive radiation is such that, within a relatively short time, many species derive from a single or a few ancestor species. From this large number of genetic combinations, only a few can survive on long term. After the rapid development of many new species, lots or most of them die out as quickly as they appeared. The surviving species are almost perfectly adapted to the new environment. The rise and fall of new species is now progressing very slowly, compared to the initial outburst of species.

There are three basic types of adaptive radiation. They are :

1. General adaptation. A species that develops a radically new ability can reach new parts of its environment. An example of general adaptation is bird flight.
2. Environmental change. A species that can, in contrast to the other species in the ecosystem, successfully survive in a radically changed environment will probably branch into new species that cover the new ecological niches created by the environmental change. An example of adaptive radiation as the result of an environmental change is the rapid spread and development of mammalSubclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorpian species after the extinction of the dinosaurs.
3. ArchipelagoAn archipelago is a landform which consists of a chain or cluster of islands. Archipelagoes usually occur in the open sea; less commonly a large land mass may neighbour them. Archipelagos are often volcanic, forming along ocean ridges or hot spots, but thes. Isolated ecosystems, such as islands and mountain areas, can be colonized by a new species which upon establishing itself undergoes rapid divergent evolution. Darwin's finchesDarwin's finches are 13 or 14 different closely related species of finches Charles Darwin discovered on the Galapagos Islands. Darwin's voyage on HMS Beagle and the finches in particular, are known to have influenced his thinking so that he would later pr are examples of adaptive radiation occurring in an archipelago.

In science fictionScience fiction generally speaking, is a form of speculative fiction which deals principally with the impact of imagined science and/or technology upon society or individuals. There are, perhaps, exceptions to (or at least, some very unusual examples of) sometimes adaptive radiation of humanHuman beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. Biologically, they are classified as Homo sapiens ( Latin for knowing man , a primate species of mammal with a highly developed brain. In spirituas is imagined. This often makes for interesting multi-species worlds.