Summary anthropology

The origin of organisms can be explained by the use of different theories that were developed using various concepts. Some of the theories have scientific proofs whereas others are majorly based on beliefs. Evolutionary theories are some of the approaches that have widely been used by scientists to support their studies on the variation of organisms. According to the theories, organisms are believed to have had a common ancestry where they all evolved from over a long period. It is, therefore, a gradual process that takes a long time for the organisms to assume the characteristics that define their identity. The process may be influenced by various factors that include different climates, different food sources, and different predators among others. Critters have not been left out by evolution and this explains why there are different types of organisms. It is assumed that reproductive isolation, genetic drift, ecological niche, natural selection, and genetic mutations play a critical role in explaining why one species of critters may evolve into two separate species that have several critical traits.