BIOLOGY - Evolution - Mutations and Natural Selection

The way we grow and develop in the womb is controlled by our DNA. Small sections of DNA, called genes, carry the code telling the body how to build itself. Usually this works fine, but sometimes those genes carry mistakes in their code. These mistakes, known as mutations, may have no effect, they may be beneficial, or they may be harmful. If the mutation is beneficial, the mutated individual will have a better chance of surviving and reproducing, with all the offspring benefitting from the mutation too. Alternatively, a harmful mutation means that that individual may not be able to survive and reproduce. As mutations in DNA are a random and ongoing process, non-beneficial and harmful genes are eventually “weeded out” of a population in a process called Natural Selection. Species evolve through a slow process of natural selection so that only the beneficial mutations are incorporated into the population, whilst the harmful ones are removed.