Why is divergent evolution important
An example is the wings of insects, birds, and bats. For more on the differences and similarities between convergent and divergent, see the table below. Discover more examples of speciation associated with divergent evolution here: Sympatric vs allopatric speciation. Join us in our Forum now! While species in divergent evolution essentially diverge and in convergent evolution merges , species in parallel evolution tend to evolve structures parallel to other species within the same environment.
Similar to convergent evolution, the traits in parallel evolution evolved in species that are not evolutionary related. The difference is that in parallel evolution the unrelated species evolved a similar mechanism to adapt to the same environmental conditions. In convergent evolution, unrelated species do not necessarily live in the same environment.
Parallel evolution differs from divergent evolution in fairly the same way as convergent evolution does. Both parallel and convergent evolution are associated with species from different evolutionary lineages. In divergent evolution, it is an evolution of a species that diverges from its ancestors. Adaptive radiation is defined as the process whereby several new species from a recent ancestral source diversify. Each of these species is adapted to utilize or occupy a vacant adaptive zone. This zone, thus, serves as an ecological opportunity for certain groups of organisms to diversify into different forms, often, in a rapid process.
However, the two concepts differ in the way that adaptive radiation deals more with small-scale evolution over a shorter span of time whereas divergent evolution looks through the evolution of species diverging from their ancestors over a relatively long span of time. Nevertheless, adaptive radiation may lead to divergent evolution over time as the species become more and more distinct from its ancestors.
Divergent evolution occurs when a subgroup of a species evolves traits different from its ancestors. The trait usually sprung from selective pressures. Such pressures drive natural selection and compel organisms to evolve.
Selective pressures may be biotic or abiotic. Biotic pressures are living factors in the environment, e. Abiotic pressures include non-living environmental factors, such as light, soil, and wind. This may be caused by a change in chromosome number or as simple as incompatible reproduction cycles. An example of adaptive radiation that led to divergent evolution is Charles Darwin's finches.
Even though their overall appearances seemed to be similar and were clearly descendants of the same common ancestor, they did have different beak shapes and were no longer able to interbreed in nature. This lack of interbreeding and the different niches the finches had filled on the Galapagos Islands led the populations to become less and less similar over time. Perhaps an even more illustrative example of divergent evolution in the history of life on Earth is the forelimbs of mammals.
Even though whales, cats, humans, and bats all are very different morphologically and in the niches they fill in their environments, the bones of the forelimbs of these different species are a great example of divergent evolution. Whales, cats, humans, and bats clearly cannot interbreed and are very different species, but the similar bone structure in the forelimbs indicate they once diverged from a common ancestor.
Mammals are an example of divergent evolution because they became very dissimilar over a long period of time, yet still retain similar structures that indicate they are related somewhere on the tree of life. The diversity of species on Earth has increased over time, not counting the periods in the history of life where mass extinctions occurred.
This is, in part, a direct result of adaptive radiation and also divergent evolution. Divergent evolution continues to work on the current species on Earth and leading to even more macroevolution and speciation. Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile.
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Evolution: International Journal of Organic Evolution, 62 2 , — Kirkpatrick, M. Speciation by natural and sexual selection: Models and experiments. Lawson, L.
Divergence at the edges: Peripatric isolation in the montane spiny throated reed frog complex. BMC Evolutionary Biology, 15 1 , Losos, J.
The Princeton guide to evolution. Adaptive radiation: The interaction of ecological opportunity, adaptation, and speciation. Evolution Since Darwin: The First, , — Mayr, E.
Ecological factors in speciation. Evolution, 1 4 , — Nagel, L. Body size, natural selection, and speciation in sticklebacks. If different selective pressures are placed on a particular organism , a wide variety of adaptive traits may result. If only one structure on the organism is considered, these changes can either add to the original function of the structure, or they can change it completely.
Divergent evolution leads to speciation, or the development of a new species. Divergence can occur when looking at any group of related organisms. The differences are produced from the different selective pressures. Any genus of plants or animals can show divergent evolution. An example can involve the diversity of floral types in the orchids.
The greater the number of differences present, the greater the divergence. Scientists speculate the greater that two similar species diverge indicates a longer length of time that the divergence originally took place.
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