Redrawing Family Tree

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.

In the quest to explain human origins it is necessary to find a species that bridges modern man (Homo sapiens) with the apes. To fill this gap evolutionists have set forth Homo erectus, who lived approximately 400,000 to 1.6 million years ago (Johanson and Shreeve1989). Although the distinctions are somewhat vague, below the neck, Homo sapiens and Homo erectus are practically Identical and Homo erectus was responsible for pioneering the use of standard tools (such as the hand axe), big-game hunting, and the use of fire (Johanson and Shreeve1989).

Discoveries relating to the human lineage are extremely exciting and often baffling. This is the case with the recent discovery of what seems to be the oldest member of the human family. A skull found in northern Chad in 2001, has been deemed the earliest relative to the human ever found. Nicknamed Toumai, and discovered by Michel Brunet and his paleontology team, this new category of human has been given the scientific name, Sahelanthropus tchaensis. What makes this skull so definitive is the fact that it dates back approximately 6-7 million years in the earth’s history (Whitfield 2002). Since the discovery there have been anthropologists and paleontologists that have

This article shows how Paleoanthropologist David Lordkipanidze and his group of archeologist discovered a 1.8 million-year-old skull fossil that could lead to knowing more about the earliest known ancestors of humans that ventured outside of Africa. Lordkipanidze’s excavation in the Georgia site known as Dmanisi. With this archeology find, it has been concluded that all early fossil humans belong to the same species known as Homo erectus. The article explains that the Dmanisi hominins had brains less than half the size of a modern human’s, and are key to understand the evolution and expansion these ancestors experienced from Africa to Eurasia. Genetic studies indicate that their expansion began from Africa about 1.9 million years ago. The article also mentions that with these new findings there can be a better ground from where to start to understand these ancestors as how they lived and socialized. Lordkipanidze does mention that the Dmanisi “were very primitive, we think there were social groups that connected with each other and learned from each other”.

Darwin once hypothesized that humans evolved from an ape like ancestor and that those ancestors most likely originated in Africa since the majority of the great apes lived there. Unfortunately, Darwin’s hypothesis was ignored for reasons such as people (e.g. Europeans) not liking of having African ancestors—not to mention the lack of evidence did not help in supporting such hypothesis. Thus, finding the missing link between apes and humans was of great important—it still is. Thankfully, through extensive research many scientists have been able to determine a clade called Hominin [7]. This clade contains humans as well as their most closely related relatives.

Three recent fossil findings believed to be hominin ancestors have been selected for description and any controversy surrounding their discovery will be discussed. The three fossils are: Homo floresiensis, Homo rudolfensis and Kenyanthropus

“How old is the oldest human fossil?,” If you had said about 700,000 years, you would probably have been right until just recently that is, “The September 1998 issue of Discover magazine”, reports that Ernesto Abbate, a geology professor from Florence, Italy, has just discovered the fossilized skull and teeth of a humanlike creature who might have lived, as far back as, one million years ago. Calling this creature Buia Man after the city in northeastern Africa where the remains were found. Prof. Abbate thinks he has discovered the earliest fossil that displays physical features associated with Homo sapiens, the species to which modern humans belong. Moreover, Buia Man says, Prof. Abbate also shows physical

Superficially, anatomically modern humans and Neanderthals have much in common. Current data suggest Neanderthals had language, religion, and shared select genes with Homo-sapiens. The standing question is whether or not these similarities are a product of gene flow. This paper will be an extensive overview of the most substantial evidence that proves or disproves any genetic and anatomical relationships between anatomically modern humans and Neanderthals.

Many of the features that distinguish Homo erectus from other hominin species—both earlier and later species—are seen in the skull. The average brain size of Homo erectus is estimated to have been roughly 900 cubic centimeters (cc.), which is larger than Homo habilis, but smaller than that of Homo heidelbergensis and other later forms. The size of the Homo erectus brain is negligibly larger than in Homo habilis when it is considered as in relation to body size—i.e., brain size increased substantially in Homo erectus, but, because body size also increased, the relative size of the Homo erectus brain is not considerably larger than that of Homo habilis. The absolute in brain size, however, caused changes in the brain case; for instance, the

A longstanding view of human evolution holds that the first hominids to leave Africa did so with the help of bigger brains, longer legs and fancier tools than those of their predecessors. That scenario suffered a major blow a couple of years ago, however, when paleontologists working in Dmanisi, Georgia unearthed the oldest human remains yet found outside of Africa---two 1.7-million-year-old skulls belonging to early members of our genus, Homo--and discovered primitive tools alongside them. Now a new finding may topple another pillar of the theory. According to a report in the current issue of the journal Science,researchers working at the same site have recovered a third skull--one that housed a surprisingly small brain.

The author of this article wrote about a recent discovery of the fossils of a new human-like species that are sparking controversy among several paleoanthropologists. According to the article, the remains were retrieved by a group of slim excavators from the inside of a deep South African cave. The age of the bones were found unclear due to the fact that it had been buried in sediments of numerous layers. Close examinations showed that the fossils had the same traits as several other species in the genus Homo. The skeletons had similar skulls, legs, and ankles while other traits such as their fingers and rib cages were slightly different to accommodate other methods of movement. Paleontologists from various parts of the world have reasoned whether or not they believe that the discovered remains had any actual relation to the human species. Nonetheless, the researchers believe that any new information from the bones could help them find out its origin, age, distribution, and deposition into the cave.

A recent finding on the western shore of Lake Turkana in northern Kenya, a semi-desert area, could hold bold new implication for the origin of man. The finding was the skull of a very early hominid which displays facial features of both modern man and early, more primitive ancestors. The findings have been dated to approximately 3.5 million years, a time period once thought to be dominated by human ancestors that did not posses any noticeable and unique characteristics held by modern man.

During both the Early Pleistocene and the Middle Pleistocene, we see a number of hominins that paved the way to modern human development (Boaz & Ciochon, 2004). One of these hominins is Homo erectus (Lewis et al., 2013). According to Lewis (2013) while it is probable that they first developed developed in Africa, it also “. . . seems likely that H. erectus first arose in East Africa and then very quickly migrated to other continents”; however, it is hard to prove this hypothesis as new fossils are found (p. 236). While H. erectus characteristics vary across continents, the majority share the same range in body size, brains, and cranial shape. H. erectus adults had robust bodies weighing more than 100 lbs. and measuring 5’6” tall. The range in H. erectus brain size is 700 to 1250 cm(^3). The most distinct characteristic of H. erectus is its cranial shape. The cranium displays a thick cranial bone, large brow ridges, a pointy nuchal torus at the posterior, low forehead development, a wide cranium base, and finally a sagittal keel (Lewis et al., 2013).

The fossils and the site from which the fossils’ were discovered were extensively researched. Measurements were taken from various parts of each skull and compared to Neanderthals found in Eurasia. From their findings scientists who researched the skulls believe that there is no direct correlation between the Homo sapiens from Africa

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.