Human Origins - The Study of Human Fossils and Other Methods

The species to which humans belong, homo sapiens, is believed to have come into existence between 100 000 - 200 000 years ago. Because this is too long ago for any written records to have existed, scientists must use other methods to gather information about our evolutionary past. The most useful of these methods have been the study of human fossils, the archeological record, and genetic analysis.

Fossils are the remains of a once living organism and they provide the best direct evidence of our evolutionary past. Not all these fossils are the same though, because fossilization is an ongoing process. Some recent fossils still contain organic matter that was once part of a living organisms. In older fossils the minerals in the soil(such as calcium phosphate) has replaced organic matter, preserving their physical shape, but genetic information can't be gained from them anymore.

Paleoanthropologists specialize in understanding human evolution through studying human fossils. By studying human fossils closely, they try to gain as much information as possible about out ancestors' anatomy, ecology, diet, mens of locomotion, and social behavior. Paleoanthropologists also work with geologists to estimate the age of fossils using several techniques.

Archeology, a subdivision of anthropology, studies the material culture that human and prehuman populations have left behind. About 2.6 million years ago, some tools began to appear in East Africa. This marked the beginning of the archeological record. By studying these tools and other artifacts, archeologists have learned a great deal about cognitive capabilities and the behavioral patterns of those who made them.

Geneticists on the other hand have drawn their own conclusions concerning human origins using modern DNA research. In 1967 Vincent Satich and Allan Wilson used current genetic data to determine the approximate date when two different groups of organisms last shared a common ancestor. Wilson and Satich used a method called the molecular clock , which holds that genetic differences occur at a constant rate over time. Using this method, geneticists have been able to determine that humans and chimpanzees share a common ancestor that is approximately 6 million years old.

To sum up - Different types of researchers uses different methods to understand our evolutionary past - including the examination of fossils, material culture, and modern genetic data.

Source: The Bedside Baccalaureate