Natural Selection

The process of evolution has been categorized into different mechanisms to explain a change in a studied species. The most well known mechanism is the theory of natural selection. This theory describes how evolutionary changes are dictated by the survival rate of reproducing specimens. For instance a dark haired artic rabbit would be easily spotted by predators and eaten thus ending their ability to procreate and pass along the dark haired gene. While the white rabbit in the same region would have a greater survival rate and would pass the white haired gene along to its descendants.

Genetic drift, much like the theory of natural selection, is based on the reproduction percentage of a certain trait within a particular species. Unlike natural selection, genetic drift theory is not based on adaptation due to need for survival; instead these changes are a function of chance. A group of insects pushed into an area of like insects with different traits by a chance wind could result in a random evolution of combined traits.

Migration is another mechanism for change within a species. An increased population resulting in territorial expansion or an external climate change resulting in the need for relocation both result in the migration of the species increasing the chance for evolution through cross breading. This mechanism is one the largest driving factors for evolutionary change in a thriving population of a particular species.

Finally mutations caused from random genetic changes are found to cause genetic evolution within a single species. The mutation mechanism of evolution does not rely on external factors to force change. However, genetic changes are caused by random circumstances driving the variations within descendants. The long term path of evolution for a distinct group can be comprised of all mechanisms of evolution creating a blended and unsystematic path of change. This is also known as natural selection.

Natural selection, commonly referred to survival of the fittest, is an evolutionary characteristic in which organisms gradually evolve characteristics that are beneficial over several generations. An organism develops a beneficial trait that enables the organism to survive easier. This trait is passed on the future generations because these decedents have a better chance of survival with this trait. This process continues until the trait becomes a part of the genetic makeup of the species. Additionally, traits that are no longer necessary to the survival of the species slowly get phased out. This theory was first brought forth by Darwin’s On the Origin of Species in 1859.

The process of natural selection results in biodiversity throughout a species. The term biodiversity refers to the genetic and species variations throughout the broad scale of an ecosystem. The results of natural selection resulting in biodiversity are best shown in an example. In a hypothetical situation, two groups of one species become separated, and are now in two different ecosystems. Each group continues to evolve, gaining traits specific to their respective areas, while losing traits no longer needed from the previous ecosystem. After generations have passed, these two groups will both still be members of the same species, but natural selection process has lead to each group being different in certain ways.

The biodiversity seen today consists of many millions of distinct biological species and is the result of 4 billion years of evolution on earth. The species inhabiting earth have either adapted to their ecosystem or they have died out from lack of food to predators. Biodiversity is extremely important for all species living on earth to continue adapting to their surroundings as they change since human life has been taking over all of the habitats of animal and other species. As human beings continue to expand into different ecosystems the species living in those areas are not having enough time to adapt to any changes and as a result the ecosystems in certain parts of the world