Compare and contrast three theories of modern human origins. What does each predict about the relationship of modern humans to Pleistocene hominins? What data are relevant to showing which of these theories is correct?

The problem of the origin of modern man among paleoanthropologists can be summarized in three different theories, in which a confusion between Homo sapiens and Homo sapiens sapiens is mixed. In this text it is the latter, whom we refer to as modern man. The problem lies in knowing what happened between the 500,000 years in which we know the morphology of Homo erectus and, approximately, the 40,000 years in which modern man is known.

R1:

- Noah's Ark Theory or Theory from Africa or model outside Africa or model of complete replacement or monogenism.

According to the most accepted theory, our species would have evolved to its current form starting from a single population in Africa. Thus, different regions in Ethiopia and South Africa have been contending for the title of cradle of humanity. However, some researchers are rewriting that traditional narrative, supported by new material and genetic tests.

According to it, modern man developed and diversified in Africa just a few hundred thousand years ago. Although there were other protohumans in other parts of the world before, all of them disappeared with the passage of time.

This new explanation of the origin of man collides with the "multiregional" theory, the most accepted so far. For this, modern man comes from Homo Erectus, a protohuman species that appeared in Africa 1.5 million years ago and spread to Europe and Asia. Over time, Homo Erectus became "archaic" Homo Sapiens that had different expressions in different parts of the world. In this way, Neardenthal man would have been the ancestor of the Europeans, that of Java for the Indonesians and that of Beijing, for the Chinese.

- The multi-regional hypothesis or model of regional continuity or polygenism, also known as the candlestick theory.

 For which a sector of researchers, think that modern man appears separately in different parts of the globe, being his multi-regional origin. The coetaneity of Neanderthals and sapiens, or modern man, today is demonstrated by the remains of several sites in the Near East, well dated and recently studied, for at least 50,000 years, all of them being associated with Middle Paleolithic industries.

 African multi-regionalism. Called the cradle of humanity, it is said that it was not in Africa but was Africa. The distinctive features that sapiens present today emerged as a mosaic in different populations scattered across the continent. Separated from each other by these geographical barriers, our ancestors evolved for a long time in isolation and each group identified some of the traits that have reached the present day, which they contributed to the entire species. Because this separation was not a constant: a measure that changes in the climate green deserts or dried forests, those first human beings came into contact or were isolated from other communities. And every time the roads were opened for these groups, miscegenation occurred, exchanging genetic material and technological knowledge in a continental melting pot that culminated in what is now Homo sapiens.

- Mixed hypothesis

Although the Theory from Africa is widely accepted, several groups of researchers cite the fossil and genetic evidence to defend a more complex hypothesis. They argue that humans associated with modern traits emerged several times from Africa, over an extended period of time, and intermingled with archaic humans in various parts of the world. As a result, they claim that the autosomal DNA of archaic human populations living outside of Africa persists in modern populations, and modern populations in various parts of the world still bear some physical resemblance to archaic populations living in those regions.

The observation that most of the genes studied to date are linked in African populations, pointing towards the importance of Africa as the origin of the most modern genetic variations, perhaps with some subdivision in the ancestral African population.

R2:

The Theory from Africa or model outside Africa or model of complete replacement or monogenism, shows that modern man was not related to the hominids present in the Pleistocene. According to this version, let's keep the chosen sapiens replaced, without mixing, any other population of hominids that we would have outside of Africa, what they usually call, at least 500,000 years ago a group of hominids underwent a series of genetic and cultural changes that They launched them into an evolutionary career that culminated in the modern human being. From that first cradle, they spread throughout the continent and, from there, to the rest of the world.

The multiregional hypothesis or model of regional continuity or polygenism, shows that modern man had a close relationship with the hominids of the Lawsuit, there was a hybridization with Neanderthals and Denisovans, this does contradict one of the original premises of the Out of Africa and, in that sense, gives a little reason to multiregionalism.

The mysterious ancestors found in the Moroccan grotto had a strange combination of characteristics, in which the flat faces of modern humans were mixed with the elongated skulls of ancient species such as Homo erectus. Despite being more robust and muscular than us, their traits link them to our species more than to any other member of the genus Homo. The lower jaw was also similar to that of modern sapiens, although much larger, but there is a striking difference in the shape of the skull, much more elongated. Our skulls are rounded in shape, but theirs were lower on the top and longer on the back. According to the latest findings, the results found that both Neanderthals and modern humans lived together in Apidima.

People living outside Africa today have an ancient trail that extends to the migrants who left that continent 60,000 years ago.

Likewise, in the mixed theory, from the genetic point of view of mitochondrial DNA and the Y chromosome, the contribution of Neanderthal and Denisova man to the gene pool of modern humans is null. The genomic study indicates that the lineages would have separated about 700,000 years ago. On the other hand, it is argued that there is a Neanderthal genetic contribution (hybridization) of 1-4% in non-African human populations and with Denisovans in populations of Southeast Asia and Oceania.

A3: A recent finding corroborates the theory of the multiregional hypothesis or model of regional continuity or polygenism.

The discovery of a 3-centimeter finger bone is the key with which a group of scientists is now replacing what they knew about the migrations of the first modern humans.

According to this finding, Homo sapiens traveled beyond Africa much earlier than previously believed.

Until now, Homo sapiens was not considered to have lived continuously outside of Africa until 60,000 years ago. The finger, however, suggests that modern humans lived in Saudi Arabia long before, about 85,000 years ago. The phalanx was found by a group of scientists in Al Wusta, a desert on the Arabian peninsula. The group of archaeologists managed to identify it among a collection of more than 800 animal bones and about 400 stone artifacts that were collected. The surprising discovery of a fossil that changes the history of the first humans. Previous excavations in Saudi Arabia have already found tools that could have been used by early Homo sapiens. However, it was necessary to find human bones.