Implications of the Sahelanthropus Tchadensis (Toumai) Discovery
Compared to the complete history of life on earth, human history is relatively brief. The earth is billions of years old and living organisms probably appeared some two to four billion years ago. Many different kinds of animals have been inhabiting the earth for hundreds of millions of years. Early hominids which are human like creatures are thought to have originated just 5 million years ago and modern humans around 100,000 years ago. There have been a recent discovery that is now challenging the appearance of the early hominids.
In the country of Chad which is located in central Africa scientists have recently made a discovery of a hominid skull. This skull was dated back to between 6 and 7 million years ago. The discovery was led by anthropologist Michel Brunet from the University of Poitiers in France. The find was named Sahelanthropus tchadensis and is nicknamed “Toumai” which means “hope of life” in an African language. The fossil find is an almost complete skull, some teeth, and a few fragments of the lower jaw. (Bower 2002)
This fossil find is completely surprising and amazing. The remains that were found represent the earliest known member in the line of human evolution. This find could be the beginning of many which could completely change our current ideas of human evolution. This pushes back the dates of human history by 2 million years. If Toumai is truly a common ancestor of humans and chimpanzees this makes the molecular clock theory wrong. The molecular clock dates the divergence of humans and chimpanzees somewhere around 5 million years ago while the Toumai discovery suggests that is was 6 to 7 million years ago. (Bower 2002)
Homini...
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...of the same kind. This is only one very small link in the massive chain of human origin. Scientists need to continue to search the globe and make more new discoveries to further challenge the norm and uncover the truth of our history.
Sources:
Bower, Bruce. Evolutions surprise: fossil find uproots our early ancestors. Science News 13 July 2002; vol. 162, No. 2, P. 19. 4 April 2004
www.sciencenews.org
Brunet, Michel. A new hominid from the Upper Miocene of Chad, Central Africa. Nature 418, 145-151. 11 July 2002. 4 April 2002
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Paoli, Laurence. Toumai: Shaking our conceptions on the earliest steps of Hominid history. Science In Africa August 2002. 5 April 2004
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Whitfield, John. Oldest member of the human family found. Nature News Service/Macmillan Magazines 11 July 2002. 4 April 2004
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Paabo’s team discovered an mtDNA sequence from a finger bone they found from around 40,000 years ago, as carbon dating is one of the most commonly used methods of determining a fossil’s age. (Hammer, 70). Also, Neanderthal mtDNA is differs severely from modern human mtDNA. For example, Microcephalin is a gene for brain size during the development of the organism.
1) Carroll, R. L. 1988. Vertebrate Paleontology and Evolution. W. H. Freeman and Company, New York.
A study performed by Martin Hausler and Peter Schmid of the University of Zurich, Switzerland, appeared in the October 1995 issue of Journal of Human Evolution, igniting controversy over the 1974 Australopithecus discoveries in Hadar, Ethiopia. The most famous of the Hadar specimens is the 3-million-year-old skeleton, “Lucy,” who was recovered by paleoanthropologist, Donald Johanson. In his article, Shreeve presents the methods and findings of Hausler and Schmid’s study as well as some counter arguments from other scientists in the field.
Allen, John S., and Susan C. Anton. "Chapter 13 The Emergence, Dispersal, and Bioarchaeology of H. sapiens." Pearson Custom Anthropology. By Craig Stanford. Boston: Pearson Learning Solutions, 2013. 200+. Print.
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Scientists thought that interbreeding would be a logical assumption to the Neanderthal conundrum. Unfortunately, any evidence of DNA from Neanderthals mixed with human DNA is difficult to come by because their fossils are usually tarnished upon finding. That is until Svante Paabo, and his research team from the Max Planck Institute for Evolutionary Anthropology, came across the remains of twenty-four Neanderthals and forty early humans.* All of these fossils were nearly 40,000 years old and were from Germany, Russia, and Croatia. Nine of these fossils (four Neanderthal and five human)
Humanity became fascinated with the idea of evolution with the work of Charles Darwin and the Scientific Revolution. People began hunting for fossils that would prove that man had an ape derived ancestry (Weiner, 1955). After various years of searching, a piece of physical evidence was found in England that was said to confirm the theory of evolution (Weiner, 1955).This confirmation came from Charles Dawson’s discoveries from 1908, that were announced publicly in 1912 (Thackeray, 2011). Dawson was believed to have found the fossil remains of the “missing link” between ape and human evolution, the reconstructed skull of Piltdown man (Augustine, 2006). The material was found in stratigraphical evidence and animal remains that were, at the time, adequate enough to confirm the antiquity of the remains (Weiner, 1955). In 1915, another specimen, Piltdown man II, was found further proving this theory (Augustine, 2006). However, this was merely a hoax proven by fluorine relative dating in 1953; the artifacts and bone fragments discovered turned out to be altered to fit the proposed scenario (Augustine, 2006). The skull found was actually composed of a human braincase that was younger than the complimentary orangutan lower jaw (Falk, 2011). Both sections of the skull had been stained to appear to be from the same person of the same age (Falk, 2011).The perpetrator of this act was never caught and there are many theories proposed for the motive of this hoax (Augustine, 2006). Many people have been taken into consideration for this crime, such as Chardin, Woodward, Hinton, and Dawson (Augustine, 2006). Nevertheless, the evidence that proves that Dawson is guilty of this crime against anthropology is quite substantial compared to the evidence...
Fragile X Syndrome is a genetic disorder that causes individuals, mostly men, to develop developmental problems and cognitive impairment. Although men are mostly affected by this disorder, it can affect women as well. Approximately one in four thousand males are affected by Fragile X while only one in eight thousand women are affected (Fragile X syndrome, 2012). Fragile X causes a variety of symptoms such as possible ADD, anxiety, delayed development of speech and language, mild to moderate intellectual disability and hyperactive behavior. Symptoms of Fragile X can start by the age of two, or earlier. Men affected by Fragile X mostly experience mild to moderate intellectual disabilities. Since Fragile X is more common in males, they tend to experience symptoms more than women do. Intellectual disabilities usually only affect about one-third of women that have Fragile X. Children with Fragile X experience anxiety and tend to fidget more than normal or have impulsive actions. Many children may also have ADD which allows them not to be able to focus as much as a normal child would. Behavioral abnormalities are a common feature of Fragile X. Biting at the hands, flailing hands are arms and gaze aversions. When it comes to deficits, they most likely occur in reasoning, processing the environment and mathematics. Individuals with Fragile X may show features of autism, this mainly occurs in only about one-third of individuals with Fragile X. Another symptom of Fragile X is seizures. Again, since Fragile X is more common in males, seizures are more common in males. While only five percent of women experience seizures, about fifteen percent of males experience seizu...
Bindon, Jim 2004 Fossil Hominids. ANT 270 Notes. http://www.as.ua.edu/ant/bindon/ant270/lectures/ hominids1.pdf Delson, Eric 1981
Trinkaus, E. (2007). European early modern humans and the fate of the Neandertals. Proceedings Of The National Academy Of Sciences Of The United States Of America, 104(18), 7367-7372. doi:10.1073/pnas.0702214104
The first group of primates was the Ardipithecus group. They were the earliest humans closely related to other primates. The Ardipithecus group evolved in Africa and took the first step upright on two feet. Sahelanthropus tchadensis was the first human species to ever walk the earth. They were the building block of more complex species to come. There were many species that started the human race such as the Orrorin tugenensis. This species was nicknamed the Millenium Man and live 5.8-6.2 million years a...
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