How to Identify the Stages of Human Evolution

Early Stages

• The earliest identified stages of man include Ardipithecus ramidus, Australopithecus anamensis, Australopithecus afarensis, Australopithecus africanus, Australopithecus robustus and Australopithecus boisei. The bodies of these early species began developing human characteristics before the skulls did. It is believed that Australopithecus anamensis walked on two feet. Australopithecus africanus fossils reveal a larger brain and the development of the canine teeth and molars. The skull of Australopithecus robustus is denser than prior species and its teeth and jaws indicate a diet that required more chewing and grinding. Australopithecus boisei had a massive jaw with smaller teeth in the front.

Homo Habilis

• The leap from Australopithecus to Homo was the large increase in brain size. It is believed that this increase in brain size enabled this species to invent and utilize tools. Another indicator is the hand grip and slightly shorter fingers of the species. The average size man was approximately 5 feet tall and weighed about 100 lbs.. It is also believed, based on the brain size, that Homo habilis may have been capable of speech.

Homo Erectus

• Homo erectus grew to a height of about 5 ft. 5 in. tall, had shorter arms, a flatter forehead and lower cranium. The skull also indicates a much larger brain than prior species. Fossil remains of Homo erectus also indicate that he had the ability to hunt, start and control fire and cook his prey. The addition to meat in his diet attributed to his increase in size.

Homo Sapiens (Archaic)

• Fossils from Homo sapiens (archaic) have been found worldwide. The shape of his forehead indicates that the growth of his brain had given him the ability to plan, reason, speak and control movement of his limbs. Weapons and tools belonging to Homo sapinens (archaic) have also been found, indicating a more socialized being.

Homo Sapiens Neanderthalensis

• Homo sapiens neanderthalensis appeared during the end of the Ice Age. Their body development conformed to survive the cold of their environment. Their body size, with shorter arms and legs, helped to retain body heat. The shape of their projected nasal cavity is thought to have provided more surface area for mucus to heat the cold air before it entered their bodies. Bones indicated a more muscular and stronger build. They also had a larger brain and artifacts that have been found belonging to Homo Sapiens Neanderthalensis indicate more-advanced socializing skills.