Anthropology
Open Access

Anatomical Changes in Human Evolution

^*Correspondence: Rithvik Singh, Department of Anthropology, Punjab University, Chandigarh, India, Email:

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Description

Human evolution is the long process of change by which humans derive from ape-like ancestors. Genetic drift, natural selection, and specification are the main factors that have shaped evolution. It is the progressive change in inherited characteristics over a long period of time and over several generations. Environmental factors like climate, temperature, availability of resources, etc., had a main role in evolution and an organism is required to develop a niche.

Even though this is not the case in all illustrations that the evolution permits an organism to regulate and increase in an environment that was previously unfavorable. Humans are primates and the physical and genetic similarities show that the modern human species, Homo sapiens, is closely related to another group of primate species, (the apes). Humans and the abundant apes (great apes) of Africa, chimpanzees (including bonobos or so-called "pygmy chimpanzees"), and gorillas share a common ancestor that lived 8 to 6 million years ago. Humans first evolved in Africa, and much of human evolution took place on that continent. The fossils of the first humans, who lived 6 to 2 million years ago, come entirely from Africa.

Changes

Most scientists currently recognize between 15 and 20 different species of early humans. However, not all scientists agree on how these species are related or which ones simply went extinct. Scientists also debate how specific early human species can be identified and classified, and what factors influenced the evolution and extinction of each species. Early humans probably migrated from Africa to Asia between 2 and 1.8 million years ago. They came to Europe a little later, around 1.5 million to 1 million years ago. Modern humans occupied many parts of the world much later. For example, humans probably first arrived in Australia in the last 60,000 years and in the Americas in the last 30,000 years. The beginnings of agriculture and the rise of the first civilizations date back to the last 12,000 years. The evolutionary process mainly involves a series of natural changes that result in species (populations of different organisms) emerging, adapting to the environment, and becoming extinct. All species or organisms come into existence through the process of biological evolution. In sexually reproducing animals, including humans, the term "species" refers to a group whose adult members interbreed regularly, resulting in fertile, i.e., offspring. Scientists classify each species with a unique two-part scientific name. In this system, modern humans are classified as Homo sapiens. Evolution occurs when the genetic material, the chemical molecule, the DNA inherited from parents, and particularly the proportions of different genes in a population change.

Conclusion

Genes represent the segments of DNA that provide the chemical code for making proteins. The information contained in DNA can change through a process known as mutation. It can also change the way certain genes are expressed, i.e., how they affect the body or the behaviour of an organism. Genes influence how an organism's body and behaviour develop during its lifetime, and therefore, genetically inherited traits can affect an organism's likelihood of survival and reproduction.