The Out of Africa or African Replacement Hypothesis is a well-supported theory that argues that every living human being is dismount from a small group in Africa, who then distribute into the wider world displacing earlier forms such as Neanderthal and Denisovans. Another name for it is The African Replacement Hypothesis. The Out-of-Africa theory was supported in the early 1990s by research on mitochondrial DNA studies. The fossils of early humans who lived between 2 and 6 million years ago come entirely from Africa. Scientists do not all agree, however, about how these species are related or which ones simply died out. In fact there is some evidence:
1.Fossils & Hominid Lineage
--Even though fossilization is quite unusual for many species including hominids archaeologists have assembled enough evidence to paint a fairly accurate picture not only of our ancestors, but the ancestors of species of humans who
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So how did they spread? While it is generally accepted that the forerunner to Homo sapiens - Homo erectus - left Africa about 1.5 million years ago to populate other parts of the world, there are two main theories about the spread of Homo sapiens. The first theory, known as the 'Out of Africa' model, is that Homo sapiens developed first in Africa and then spread around the world between 100 and 200,000 years ago, superseding all other hominid species. The implication of this argument is that all modern people are ultimately of African descent. The other theory, known as the 'Multiregional' Model, which basically means homo erectus left Africa 2 mya to to become homo sapiens in different parts of the world. The Multiregional Continuity Model contends that after Homo erectus left Africa and dispersed into other portions of the Old World, regional populations slowly evolved into modern
Humans developed in Africa. “…, indicates that the earliest stages of human evolution were also played out in Africa.” (Page 36)
Science researcher Christopher Stringer and science writer Robin McKie state that modern humans first developed in Africa and then spread to other parts of the world.
For many years there has been a debate over where modern humans originated from. The first theory, out of Africa, discusses modern humans evolving in Africa. They migrated out to Eurasia and as the time went on their species evolved independently and developed into distinct species. All other human populations were eventually replaced with no interbreeding involved in the process and Homo sapiens had successfully dominated the rest of the world. On the other hand, the second theory, regional continuity, says that our earliest hominid ancestors had departed Africa and spread into other parts of the world later evolving into modern human beings. In this paper I will discuss the Regional continuity theory and elaborating on the Out of Africa theory. Evidence based on fossils, artifacts, and other crucial components will be discussed. Based on the evidence found I will come to a conclusion as to which theory I think best fits the origins of humans.
The Journey of Man was an interesting non-fictional anthropological literary piece where the author sought to explain how modern humans came to inhabit the world we know today. He began by talking about the mitochondrial DNA passed from mother to daughter, or the maternal line. Using this it was discovered that all people had a common female ancestor who lived in Africa about 200,000 years ago. This was one of the first steps in supporting the out of Africa hypothesis. However, mtDNA could not give all the answers to how humans moved throughout the world, and for that he turned to the male Y chromosome. By examining this, he and many other geneticists discovered the different changes throughout populations, and could estimate how long ago they occurred. According to Wells, modern humans were in Africa 60,000 years ago, and from that point began to migrate outward. For each new area, such as Asia, the Middle East, Australia, and others, there were specific polymorphisms on the Y chromosome that defined each population. By using this technique, he was able to map out when modern
According to anthropologists the first human beings lived in Ethiopia, Africa around 2 million years ago for example: Lucy known as the oldest human found there. The most probable reason why the first human left Africa is because of the Ice Age. The cold made life so difficult to survive and somehow reduced in their population. They went through a land bridge, which existed to connect North America and Asia during the Ice Age.
Chris stringer is the author of Lone Survivor How We Came to Be the Only Humans on Earth. Stringer covers a wide variety of topics in his book. He talks about the modern technology we have now that makes it easier to identify fossils, bones, dates, etc. He also mentions how the human gene became what it is today, the Homo sapien. Stringer argues that Homo sapiens did not originate in a single region of Africa. Instead, different populations coexisted across the continent with other species like Homo erectus, and they exchanged genes, tools and behavioral and survival traits before they migrated to Europe.
Some researchers believe the Out Of Africa expansion took a southern route, following the Indian Ocean coastal boundary down in to Indonesia and finally into Sahul (Bar-Yosef and Belfer-Cohen, 2013; Derricourt, 2005; Field and Lahr, 2005). However, genetic testing of aboriginal inhabitants of Sahul favors a combination of southern and northern routes. The northerly migration path traversed through the Altai Mountains, and shows a consistency with Denisovan genetics (Cooper and Stringer, 2013:321; Davidson, 2013:3). Modern human gene flow with Denisovans is believed to have occurred in the mainland area of Asia, before migration to Sahul (Cooper and Stringer, 2013:322; Reich et al.,
The Out-Africa-Theory that has been heavily sided with is the hypothesis that remains the most likely to have happened. Not only because that is the theory that has the most scientific evidence but also because that is were the remains of the oldest primate fossil on all seven continents have been found. Even though the recent evidence in Asia is very convincing, there is too much noteworthy evidence found in Africa that an not be ignored. Moreover, such a new theory is lacking a substantial amount of evidence and investigation in order for it to become convincing theory. This leads the scientific world to side with the fact that we have deeper-rooted ancestry in Africa.
timeline of modern humans, Homo sapiens, and how long they have been in existence. According to mainstream science, popular belief holds that the history of our species is confirmed to be confined to the past 12,000 years. This figure is a culmination based on what we know about evolution and what we have been able to gather through fossil analyzation and dating of artifacts as well as human remains. Although the subject of human antiquity, also referred to as human origins, does not prompt a great deal of debate there may actually be the need for some. A reexamination of the notion that humans have only existed a mere 12,000 years should be considered as there may be evidence to support a much greater antiquity of modern human life. Alternative researchers have offered up evidence of “forbidden archeology” that contradicts the mainstream beliefs of human origins, however these discoveries seem to have been swept under the scientific rug.
One conceivable clarification is that a huge number of years prior, present day and bygone people in focal Africa interbred, adding to known cases of interbreeding – with Neanderthals in the Middle East, and with the cryptic Denisovans some place in southeast Asia.
According to physical evidence, and theories, scholars have concluded upon a whole hypothesis. Based on their knowledge and belief, modern humans diverged from Homo sapiens between 200,000 and 150,000 years ago specifically in Africa, that between 125,000 and 60,000 years ago members of Homo sapiens left Africa, and that these
Human origins, evolution, and diffusion are important for understanding the history of Africa. African historians take pride in the fact that Africa is most certainly the birthplace of humanity. There is evidence showing that humanity began in Africa by remains left behind by human groups and societies. They have retrieved fossils of living organisms, and even written records, like cave drawings. Dating back millions of years ago Africa provides the best time line of human development because other parts of the world do not have evidence dating back as far as in Africa. Where did humanity and human history begin? There are theories supporting both that, humans evolved from various parts of the world, and that humans rose in Africa then migrated to other parts of the world and continued to develop. The theory that has the most support is that humanity rose in Africa then moved to other regions of the world. Africa is indeed the home of humanity but because Africa is where humanity began they were not able to be at the top of the evolutionary ladder because their global location did not allow them to develop faster. Human history in general is difficult to understand but we can look at the past to learn more about where we came from and how our societies have developed.
The ‘out of Africa’ theory implies that Anatomically modern humans evolved in East Africa between 400,000 and 200,000 years ago and began to disperse throughout the world roughly 70,000 to 135,000 years ago. In 2011, scientists came to the conclusion there were likely two major waves of migration out of Africa - the Early northern Africa dispersal and Southern Route dispersal.
There has been a great deal of heated debate for the last few decades about where modern Homo sapiens originated. From the battle grounds, two main theories emerged. One theory, labeled “Out-of-Africa” or “population replacement” explains that all modern Homo sapiens evolved from a common Homo erectus ancestor in Africa 100,000 years ago. The species began to spread and replace all other archaic human-like populations around 35,000 to 89,000 years ago. The rivaling opinion, entitled the “regional continuity” theory or “multiregional evolution” model refutes this theory and states modern humans evolved from various species of Homo erectus who interbred with others that lived in
Human evolution according to research started over 6 million years ago. The outcome of the evolution process is the current human beings. Scientific studies have revealed over the years a remarkable affinity between the chimpanzees/Apes and human beings. Even though this reality is not a definitive prove that human beings evolved from apes, it does show that the human beings are in one way or another related to other primates. Scientists suppose that the humans and the primates shared a common ancestor. The subject of what makes humans what they are and their origin has been the exclusive purpose leading to many scientific studies globally (Coolidge & Wynn, 2011). Studies believe that Africa was the origin of evolution millions of years ago. Fossil remains have been discovered in different parts of Africa as well as other regions of the world. Different hominins have been discovered around the world in the last 1 million years. Thus, the different discoveries have led to comparisons between the various species of hominins to clarify on their similarities as well as differences. This essay seeks to explain whether they were distinctively different species or regional versions of the same species.