This cave has produced a 2 million year old mandible fragments with features supporting both ideas of origins from the Chinese and West, not yielding to a single, simple explanation. As to where these apes made their signature development onto the open, flat land is debated indefinitely. Approximately 1.7 million years ago, Homo erectus arose in Africa and shortly thereafter spread to other continents, as most scientists believe. As they expanded their range and increased in population, H. erectus may have exterminated H. habilis. Then transition from H. erectus to H. sapiens occurred about 400,000 years ago, and the dispute is over the place of origin of modern humans.
According to the Microsoft Encarta Encyclopedia ’98, the fossil evidence for direct ancestors of modern humans is divided into the category Australopithecus and Homo, and begins about 5 million years ago (See figure 1). Between 7 and 20 million years ago, primitive apelike animals were widely distributed on the African and, later, on the Eurasian continents (See figure 2). Although many fossil bones and teeth have been found, the way of life of these creatures, and their evolutionary relationships to the living apes and humans, remain matters of active discussion among scientists. The evidence for human evolution begins with the australopithecines. All the australopithecines were bipedal and therefore possible hominines.
The species for which humans belong to are called Australopithecines. This generation of species departed from their ancestors of chimpanzees about 6 million years ago. In Africa is where you can find the oldest fossils from passed humankind ancestors. Africa is known for finding evidence of the key stages of the evolution. In the 1920’s there were countless number of Australopithecus fossils found through the East and South of Africa.
There is evidence of modern humans in the anatomical sense found in Africa at the same time as Neanderthals, furthering the idea of speciation. From an archaeological standpoint, there were similarities between Neanderthals and Homo sapiens at first. However, Homo sapiens developed “modern thinking,” whereas in Neanderthals, there is no evidence of this. These Homo sapiens would eventually migrate, and Neanderthals disappeared. From a genetic standpoint, humans have little genetic variation, but the most genetic variation is found in Africa.
Hominins comprised of many species actually, including but not limited to, Australopithecus afarensis and Homo erectus. Homo erectus may have been a direct descendant of modern Homo sapiens. These species hold strong evidence that they are the missing link between apes and modern humans. There are many pieces of evidence that lay the path of evolution from these species to modern humans, “…these include anatomy, living primate behavior, and genetic relationships” (Stanford, 237). Australopithecus afarensis comes first, existing about 3.9 to 2.9 million years ago, with intermediate anatomical traits between living apes and modern humans; their fossils were found in Africa (Yukimoto).
It suggests that modern humans are the product of speciation during the late Pleistocene in Africa. Homo sapiens eventually migrated out of Africa to Eurasia, and replaced all other human populations, without interbreeding. Some of the replaced populations are believe to be the Neanderthals and the Homo erectus. The second theory proposes that modern human evolution happened trough emigration, this is known as the multiregional evolution model. This model assumes that modern humans have an ancient rather than a recent African origin.
Some scientists believe in the hypothesis known as the Multiregional Theory. This theory states that Homo erectus left Africa about two million years ago and from there migrated to Europe and Asia. These H. erectus then evolved, simultaneously, into Homo sapiens, or the modern looking and culturally evolved humans we are today. Another hypothesis that has been presented is the Uniregional Theory. This theory states that although Homo erectus did migrate out of Africa into these areas, Homo erectus evolved into Homo sapiens in, and solely in Africa.
The population of Homo antecessor that remained in Africa evolved into Homo sapiens. Another possibility is that Homo antecessor is ancestral to both Homo sapiens and Homo neanderthalensis. The Neanderthal was not human. Genetic evidence from a comparison of human and Neanderthal mitochondria shows that while chimpanzee and human lineage's diverged four million years ago, the Neanderthals diverged over 550,000 to 690,000 years ago. Human trunk and limb bones of Homo antecessor, recovered from the Ran Doling site, in the Sierra de Atapuerca have been dated at about 780,000 old and are said to represent the last common ancestor for Homo sapiens and Homo neanderthalensis.
To the ongoing question as to how humans evolved has still been a debate over several decades. Homo sapiens is a scientific name given to humans. Homo sapiens are classified under the kingdom-Animalia, phylum-chordata, class-mammalia, order-primates, family-Hominidae, genus-Homo and species-sapiens. According to Linnaeus Carlos, scientific way of classifying living organisms (Relethford, 2010). According to Relethford, Hominin is a tribe that comprises of humans and their closest ancestor.
It is clear that the evolutionary tree is far bushier that at first appeared. While the human lineage split from that of the African apes some 5-10 million years ago, this new evidence suggests possible new lines from which humans evolved. It shows a far greater diversification of human evolution prior to the emergence of the Homo genus. The newly discovered skull has a small ear hole, like those of chimpanzees. However, it shares other features of early hominids, such as a small brain.