On of the most important contributions made to the science of evolution by Charles Darwin is the concept of natural selection. The idea that members of a species compete with each other for resources and that individuals that are better adapted to their lifestyle have a better chance of surviving to reproduce revolutionized the field of evolution, though it was not accepted until several decades after Darwin first proposed it. Today, natural selection forms the basis for our understanding of how species change over time.
Natural selection may act to change a trait in many different ways. When selection pressures favor the average form of the trait, selection is said to be stabilizing. Directional selection occurs when selection pressures favor one extreme of the trait distribution. Selection is disruptive when the average form of the trait is selected against while either extreme is unaffected.
In addition to natural selection, there are two other types of selection. Sexual selection, which Darwin believed was distinct from natural selection, involves the selection of traits based on their role in courtship and mating. Artificial selection is the selective breeding of species by humans to increase desirable traits, though the traits do not necessarily have to confer greater fitness.
Natural Selection Paper
1502 WordsSep 18th, 20087 Pages
Natural Selection Paper Natural selection is considered one of the most important processes for a variety of species and the environment which allows the fittest organisms to produce offspring. To prevent a species from extinction, it is necessary for them to adapt to the surrounding environment. The species which have the ability to adapt to new surroundings will be able to pass their genes through reproduction. Within the process of natural selection, it is possible for the original genetic make-up of a species to become altered. The team will report on the different processes of basic mechanisms of evolution, how natural selection results in biodiversity and why biodiversity is important to continued evolution. The sources of genetic…show more content…
Why Biodiversity is Important to Continued Evolution
The three levels of biodiversity are as follows: diversity of the ecosystems, diversity of species within the communities and diversity within species. The loss of species within the ecosystems and within the community can cause a catastrophic result, as species live and feed on other species. Species close to extinction are endangered species, therefore protecting them from predators and offering the chance to reproduce and repopulate. Unfortunately, with little support within the environment, a species can become extinct due to population density. Proper monitoring of an endangered species is required in order to keep species actively reproducing and changing with the environment around them.
There is another side to the biodiversity of the evolutionary field, as the population weakens the species start the inbreeding of smaller populations, thus playing a role in the extinction of a species. Inbreeding is reproduction among members of a species that are genetically similar. The genetic inbreeding is designed to bolster populations of species whose numbers are in decline. However, when only a few species or varieties of a species are cultivated or survive, the genetic diversity of the organism declines, and population is more vulnerable to being wiped out by new diseases or climate changes because of the inbreeding (Alters, 2000). Conservation biologists recognize that biodiversity can be sustained only