Human Evolution Anthropology -the study of humans, their origins, their races, their physical characteristics and their cultures. Paleoanthropology - The study of ancient humans and human-like creatures using fossils. Characteristics of human fossils Since it is difficult to determine what fossils are considered human, scientists have come up with 5 characteristics. 1. Bipedalism or walking upright on 2 feet. This is determined by the shape of the pelvis 2. Brain size must be similar. In order to find brain size you must measure the skull. Humans/Homo sapiens have a large brain. 3. Teeth and jaws in human are similar. Humans have large front teeth and small molars, and the jaw itself is a rounded U shape. Apes have small front teeth, large molars and V shaped jaw. 4. Use of tools is another indication of humans. In order to use a tool one must have an opposable thumb. There are other animals that have opposable thumbs but in humans it is highly developed. 5. Cultures indicated by what objects were found along with the fossils. If they found small animal bones it can be inferred that they ate meat. If they found large animal bones then it can be inferred that these people could work together to hunt. If they found charred bones it could be inferred that they had the use of fire. Phylogenetic Tree Indicates the probable pathway of evolution Phylogenetic Tree of Humans The phylogenetic tree of humans is a very well accepted pathway. About 12 million years ago there is a fork in the tree where scientists and anthropologists believe human-like animals(hominids) separated from the apes. Hominids Apes Contrary to popular belief, scientists do not believe that human evolved from apes but that they had a common ancestor Common ancestor For awhile many scientists believed that this common ancestor was a human-like creature called Ramapithecus. Unfortunately because the only fossils of this organism that can be found are jaw bones and teeth, it can not be determined whether it is actually a human ancestor. An early ancestor of humans is a human-like creature called Australopithecus afarenis. This was one of the first complete skeleton fossil that was found. The fossil was believed to be a female. Its pelvis was believed to be made for walking upright. But her brain was only 400cm3 The next main character in the path of evolution is Homo habilis. This name means handy man or tool user. This is the first group of fossils that were found to be clearly human. They existed about 2 million years ago and were most likely the first to use tools. They have significantly larger brain but it is still less than half the size of current humans. Next on the phylogenetic tree is Homo erectus. They existed about 1.5 million years and their brain size is about 800cm3. Around this time man’s jaw began to be less V shaped and more U shaped The Neanderthals • This is the earliest group of fossils to be classified as Homo Sapiens. These people appeared about 80,00years ago and became extinct about 40,000 years ago. Human Neanderthal The Neanderthals were thought to be fairly intelligent, fully bipedal and had strong muscles in the chest and arms. They had the ability to use fire and tools. Cro-Magnon Man • It seems that CroMagnon man and Neanderthal man coexisted for a period of time. • These people are modern in appearance. Cro-Magnon Man • Cro-Magnon man was far more advanced than Neanderthals. • They had the ability to make excellent tools, domesticate animals and plant food.