Microevolution: The Role Played By Natural Selection In Evolution

The Role Played by Natural Selection in Evolution.

Evolution is the progression by which different kinds of living organism are thought to have developed from earlier forms during the history of the earth, which means it is the process of change in the inherited traits of a population of organisms from one generation to the next; the genes are passed on to the organism's offspring. [2]

Microevolution happens on a small scale (in a single population). Microevolution is a change in gene frequency within a population, it can be observed over short periods of time such as between one generation and the offspring, for example the frequency of a gene for pesticide resistance in a population of crop pests can increase. Such a change might come about

All of the changes, diversifications, and extinctions that happened over the course of life's/Earth’s history are the patterns of macroevolution, you cannot observe them but can use other methods to find out about the past and compare it to the current individual. Regardless of their differences, evolution at both levels depends on the same thing, evolutionary change that is mutation. [4]

Mutations in genes can produce new or altered traits in an organism. In sexually reproducing species, new combinations of genes are produced by genetic recombination, like in humans, when the DNA is a mixture of the DNA from the parents. This can increase the variation in traits in an organism. Evolution occurs when these genes become more common or uncommon in a population. [2]

Evolution can also be defined as the change in allele frequency in a population called the gene pool. New alleles are usually generated by mutations in genes; these are changes in the base sequence of DNA that occur during DNA replication. Some individuals are better adapted to the environment, they have an allele that increases their chance of survival, making them more likely to survive, reproduce and pass on their genes to the next generation. So the frequency of the beneficial gene increases from generation to generation. This is the process of natural

Charles Darwin came to understand that any population consists of individuals that are all slightly different from one another. Those individuals having a variation that gives them an advantage in staying alive long enough to successfully reproduce are the ones that pass on their traits more frequently to the next generation. Subsequently, their traits become more common and the population evolves. Darwin called this "descent with modification." [3]

Darwin's use of the phrase "survival of the fittest" is often misinterpreted. What makes an individual fit all depends on the environment at the time and the combination of traits that are most suited to flourishing in it. From an evolutionary viewpoint, the fittest individuals are simply the ones who have the combination of traits that allow them to survive and produce more offspring that in turn survive to reproduce.