Neanderthal Extinction
Neanderthals and modern humans coexisted for well over 100,000 years. Then suddenly Homo neandertalensis began to die out and surrender the earth to Homo sapiens. Paleontologists and anthropologists have entertained several possibilities to the causes of this event: interbreeding among Neanderthals and humans, competition for natural resources, and Darwin’s theory of “survival of the fittest.” What the real cause has been has plagued scientists for years. Now, due to an international research team from Germany, those possibilities have been even further deduced, making it easier to pinpoint the exact reason Homo neandertalensis became extinct.
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)
contained mitochondrial DNA (mtDNA), completely intact. Mitochondrial DNA is tougher than the DNA found in cell nuclei; it is also found in the cytoplasm of a fertilized egg and is passed only through maternal lineage. This makes it much easier for the team to study and makes testing more accurate.
Paabo’s team, from Leipzig, Germany, used a method of amino acid content as a way of measuring extractible DNA from the bones. The amino acid method was a...
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...ut there on what happened to the Neanderthals, such as competition or fighting. Scientists also are aware of the fact that mtDNA is only carried from the mother. This means that there may still be evidence of interbreeding out there that is carried from the male.
Our technology is not yet strong enough to rule out both sexes as a carrier of common genes. Therefore the case of interbreeding still remains to be closed. However Paabo and his team are confident that their research has proved that Neanderthals could not have died out solely because of interbreeding. Scientists are still trying to conclude what exactly did the Neanderthals in; this discovery brings them one step closer, but not completely to the edge.
Source
All references and resources are taken from the Public Library of Science, Biology March 2004 issue and from Science March 16, 2004
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...
Over the last few hundred years, more and more has been added to the world’s fossil collection, fossils from all over the world. New theories have been created and old theories have almost been proven about the evolution of man. For example, we have proof that different species of man existed with certain types of DNA sequences and instincts, some we may not have anymore, or some that other species did not have back then. Even though it is subjected to much debate, one of the most widely accepted theories however, is that Homo sapiens interbred with the slightly more primitive species of man, the Neanderthal.
U.S. Department of Energy, Office of Science. (2009). DNA Forensics. Retrieved from Human Genome Project Information: http://www.ornl.gov/sci/techresources/Human_Genome/elsi/forensics.shtml
Soon after Watahantowet’s story, the novel’s main characters, John and Owen, are introduced. One day, while playing baseball, John’s mother, Tabitha, was killed by a foul ball hit by Owen. Nobody had expected that Owen, who was very small and a poor baseball player, could hit a ball so hard. Owen tries to explain to John what had happened: "GOD HAS TAKEN YOUR MOTHER. MY HANDS WERE THE INSTRUMENT. GOD HAS TAKEN MY HANDS. I AM GOD'S INSTRUMENT" (90). Owen believes that God had used his hands to hit the foul ball which killed Tabitha. Tabitha’s death was terrible for John and Owen, who also saw Tabitha as a mother to him. To show that he still loved Owen, John gave him his most prized possession, which was a stuffed armadillo. Later, when Owen returns the armadillo to John, he amputated its claws, which symbolizes the loss of a source of protection in their lives. Also, by removing the armadillo’s claws, Owen shows how he wishes that he could take away his own arms that caused the death of
In certain situations, it is necessary to identify DNA retreived from a sample. When there is a
Around 1.8 million years ago, two hominids were born, first the Homo Erectus and then the Neanderthals. Although the two very different humans. However, were they that different? Our ancestors were very versatile hominids. They lived in various places and lived in a variety of ways. The Homo Erectus and Neanderthals were all special in their ways. They had similarities and differences that set them apart. They had similarities, but in the same way, their differences helped them survive if they had not adapted to how they lived they would have lasted the same time that their ancestors have lived. The Neanderthals lived for an average lifespan 30 years. They had to have some mistake that decreased their lifespan because if the Homo Erectus had done the same, there’s a chance that we might not be here now. Their differences set the future that we live in today. These
Neves, A. M., & Serva, M. (2012). Extremely Rare Interbreeding Events Can Explain Neanderthal DNA in Living Humans. Plos ONE, 7(10), 1-10. doi:10.1371/journal.pone.0047076
Australopithecus afarensis who existed 3.5 million years ago and a 4.4 million year old skeleton of an Ardipithecus ramidus are the closest science has come to discovering the human lineage. Shattered Ancestry an article written by Katherine Harmon discusses the remains of two hominids found within Ethiopia. These skeletal remains have created a huge controversy within the topic of evolution questioning many assumptions that have been made referencing the human lineage. The skeleton of the Australopithecus afarensis was named Lucy and was discovered in 1974. The evidence of her walking upright on her two feet essentially guaranteed her a spot in the human lineage line. Lucy was a chimplike ape that was said to walk upright making scientists believe the human ancestry was simple. The complete skeleton found in Ethiopia of an Ardipithecus ramidus named Ardi completely changed all assumptions made from scientists about the complexity of the human lineage. These remains have encouraged researches that the human line is not the only lineage to have evolved but the chimpanzee line has undergone drastic changes as well. There are many traits that researchers have always directly linked to the human lineage however since these discoveries occurred researchers are reconsidering. The recent discoveries that have shattered what has always suggested what linked a species to the human lineage have changed the certainty of whether it is possible to confidently identify the human’s last common ancestor. Majority of scientist had forgotten that there would have been many hominid species living together at one time. New theories have been suggested since scientists revealed that the foot of a hominid found called the Burtele site was found ju...
Rienzo, Anna Di. Wilson, Allan. 1991. Branching pattern in the evolutionary tree for human mitochondrial DNA. Evolution 88: 1597-1601.
There is evidence to suggest that Homo neanderthalensis and Homo sapiens had coexisted for approximately 35-40,000 years, (Fagan 2010) from around 60,000 years ago to 25,000 years ago when they finally went extinct (Gibbon 2001). Anthropologists are still uncertain what the cause of their extinction was. This paper will analyze three main theories of Neanderthal extinction. The first theory is the competition theory, which claims that the Homo sapiens and Neanderthals had to compete for resources, ultimately leading to their demise. The second theory I will discuss is the climate change theory, which claims that Homo sapiens lived while Neanderthals died because they were better adapted to the climate. The last theory I will discuss is the possible “extinction through absorption” theory which claims the Neanderthal interbred with the Homo sapiens and became one species. In this paper I will also be comparing the technologies, and diets of both species. In addition, I will look at the anatomic relation between the Neanderthals and Homo sapiens, how their body shape and size differed, and if this gave any advantage to one side or the other. My thesis for this paper will state that Homo sapiens and Homo neanderthalensis had co-existed but the disappearance of the Neanderthal in Eurasia is due to the appearance of the more culturally advanced and genetically superior Homo sapiens and the failure of the Neanderthal to adapt in an evolving climate.
From the ancient bones of the Neanderthals, scientists have been able to extract small amounts of DNA. The DNA comparisons to modern humans show no relationship, implying evolutionary separation (Kunzig, 159). Some anthropologists say the small sections of DNA found are not conclusive evidence, because modern humans show just as much variation in DNA. These people point out that individuals such as the “Portugal Kid” are hybrids of Neanderthals and modern humans, showing there was gene trading. One argument against this is that there is no skull from the ‘Portugal Kid” so it is hard to compare it to Neanderthals. Also, it is known that closely related species can breed and their offspring can be fertile, but they are still separate species (Kunzig, 161).
Some studies have found “that atmospheric CO2 concentration is approximately 383 parts per million by volume (ppmv), a level not seen in at least 650,000 years, and it is projected to increase by 0.5% per year throughout the 21st century.” (Guinotte) “This is because…the ocean absorbs about a third of fossil fuel emissions, but this amount is likely to increase to 90% in the future.” (Bralower) As a result, “the chemistry of the world's oceans is changing at a rate not seen for 65 million years, with far-reaching implications for marine biodiversity and food security, according to a new United Nations study...” (Knight) “…This change is cause for serious concern [for] many marine organisms…, [because they] may not be able to adapt quickly enough to survive these changes.” (Guinotte)
Global warming has been a continuous problem that has escalated over time on our planet Earth. The main cause of global warming is because Carbon dioxide and other warming pollutants are gathering in the atmosphere and laying over it like a thick sheet as well as its effect on the ozone layer. This is trapping the sun's heat and causing the planet to grow increasingly warmer as well as a variety of other weather shifts. Over the past 50 years, Earth’s tem...
“The scientific study of how humans developed did not begin until the 1800s in Europe. Until that time, people relied on religious explanations of how humans came into existence. Starting in the 1500s a scientific revolution began to sweep Europe. Thinkers started using scientific methods and experiments to try to better understand the world and the creatures living in it. Eventually these methods were turned to the question of human origins” (The Nature Of Human Origins, 1). Earth made it possible for species to change over time because Ancient Earth provides ability to plenty of time.The Homo Sapien a is very complex creature. The species started off very simple by living in caves and surviving with little food and then later evolved into a species that were able to do many more complex things. The first species was Sahelanthropus tchadensis They were one of the most simple humans in that time period and on. They had very small skulls compared to Homo Sapiens today and their motor skills were just the same. We have evolved and changed for the better both mentally and physically. The Evolution of Homo Sapiens started off simple, such as the Neanderthals, and now we are the most advanced species to ever walk the planet so far.
Chasing Ice covers the long debated topic of global warming and whether or not human activity is currently causing global temperatures to rise. Evidence suggests that increased carbon dioxide emissions over the past couple hundred years are responsible for the warming of the Earth’s surface, and thus increasing the levels of the ocean due to an accelerated rate of ice melting. We discussed this same topic in class and how humans are contributing to the greenhouse effect which plays a large role in trapping these unnatural amounts of gases such as carbon dioxide in the Earth’s atmosphere and causing a rise in the number of natural disasters around the world.