Evolution can be defined as the process through which the characteristics of a species undergo changes over a number of generations through the process of natural selection. There are different mechanisms that try to explain the evolution process and these are mutation, migration, genetic drift and natural selection. However for natural selection and genetic drift to take place there must exist a certain type of genetic variation. To begin with natural selection can be defined as the process through which organisms that are better adapted to a certain environment survive and produce fertile off springs. Organisms that do not seem to adapt in that particular environment are left out.
When speaking of a specific change in a creature, it would be called and adaptation (Wilreker, 2). There are several mechanisms for adaptation (Wilreker, 3). One mechanism is natural selection (Wilreker,3-6). Natural selection is the idea that, in nature, some members of a species are better suited to surviving in their environment than others (Wilreker, 4-6). The creatures may have some gene that helps make even a small change in them that makes them more likely to survive.
If all the organisms had been genetically identical they may have all been killed. The species that survive are likely to live longer and pass on their useful genes to future generations. The change in a species over time is called evolution. There are two types of variation; continuous and discontinuous variation. Discontinuous variation is when there is a complete range of measurements from one extreme to the other for a normal characteristic, such as human height.
The forces of natural selection on the evolutionary processes in humans can have a broad range of effects on the characteristics of humans. There are no concrete answers to some of the questions proposed in this paper, but time will soon tell exactly how the evolutionary mechanisms have effected the human race. The human species will continue to evolve as long as the mechanisms of evolution and environmental factors act upon us.
Essay on Evolution There are many mechanisms that lead to evolutionary change. One of the most important mechanism in evolution is natural selection which is the differential success in the reproduction of different phenotypes resulting from the interaction of organisms with their environment. Natural selection occurs when a environment makes a individual adapt to that certain environment by variations that arise by mutation and genetic recombination. Also it favors certain traits in a individual than other traits so that these favored traits will be presented in the next generation. Another mechanism of evolution is genetic drift.
These terms can be used inter-changeably. Before one can understand the Modern Synthesis and this analysis there a few defintions that must be explained in order to grasp the concept, espically if a person is not familiar with biological terminology. This list of definitions does not have to be read fully but is provided to refer to when a biological term is not understood... of course maybe not every term that isn't understood, but the majority. -Allele-one of a pair, or series, of alternative forms of a gene that occur at a given locus (location) in a chromosome. -Fitness-the number of offspring left by an individual, often compared with the average of the population or with some other standard, such as the number left by a particular genotype.
A biological definition is, more specifically, "any change in the frequency of alleles within a gene pool from one generation to the next (1)." Darwin's theory of evolution is composed of many parts. These parts include the belief that life is constantly changing and is not a static system. Also included in The Origin of Species is the idea of common descent, which basically states that all species are related because they have all evolved from a common ancestor. A third contention of Darwin's theory of evolution is that species change gradually over time by a process of inheriting very small differences.
The significance of Genetic Diversity is important as it helps in maintaining the gene pool. An individual or a whole population's ability to tolerate stress from any given environmental factor is defined by the huge variety of gene sets. Genetic Diversity and mutation: Mutations are defined as changes in the genetic sequence. Mutations are main cause of diversity among organisms. Because these changes occur at many different levels, and they can cause widely differing consequences.
Within these organisms there are different variations. Those variations are then inherited from parent to offspring; generation after generation. The organism with inherited characteristic that help with survival and reproduction are selected amongst the different variations of that organism. They are then able to reproduce more than others and therefore they are able to pass down their traits to one generation on to the next. Darwin’s theory of natural selection explained adaptations that helped a species to survive.
Darwin writes on how a species will adapt to its environment given enough time. When an animal gains a genetic edge over its competitors, be they of the same species or of another genus altogether, the animal has increased its chance of either procreation or adaptation. When this animal has this beneficial variance, the advantage becomes his and because of this, the trait is then passed on to the animals offspring. The theory of natural selection is not limited to inheritable and beneficial variations of a species. It also relies a great deal on the population growth and death of a species.