One way man has evolved over time is the brain. One of the earliest human to be found was during the Homo habilis period - million years ago (Mcnamme, ,p) Researchers found that humans in this era had a brain capacity between mL May 29, · Man is a product of evolution. Therefore human evolution is intimately related to the origin of life and its development on the face of earth. It is customary to speak of evolution ‘from amoeba to Man’, as if the amoeba is the simplest form of life. But in reality, there are several organisms more primitives than amoeba, say for example viruses. The evolution from a self-replicating organic molecule to a protozoan, like amoeba, is the most complex step in evolution, Estimated Reading Time: 3 mins Evolution is the theory proposed by Charles Darwin and argues that organisms change physically over time. Part of Darwin’s theory of evolution is the idea of natural selection. Darwin also stated that organisms must have a common ancestor. The theory of human evolution is that humans evolved
Essay on Human Evolution: Top 6 Essays | Biology
An organism reproducing mechanism that provides variable organisms. Changes to the organism are largely random and effect future generations. They are made without regard to consequences to the organism. A changing environment which screens organism changes, evolution of man essay. The environment provides stress on the variable organisms that selectively allows, through competition, certain changes to become dominant and certain others to be eliminated, without consideration for the future of the mechanism.
That same process provides mechanism organism disintegration if a strong screening environment is not present. Evolution is a two-way process which does not always work to the long term advantage of the organism and in fact often becomes quite deadly to a given species and thereby eradicates it. The evolutionary process is bidirectional in its effect. It may, depending on the environment, either improve a given characteristic or decay it. Since the first step in the process is largely random and most organisms are quite complex, almost all of the variations are harmful.
A characteristic of a species advances if the environment is harsh, since most harmful variations to that characteristic will be eliminated through death and suffering at a rapid rate, leaving only the inconsequential and helpful changes in the lineage. If the environment is benign with respect to the capability of the species then the harmful changes are not eliminated and the species will degenerate to a point of balance with the environment.
Human evolution is the part of biological evolution concerning the emergence of Homo sapiens as a distinct species from other hominans, great apes and placental mammals. It is the subject of a broad scientific inquiry that seeks to understand and describe how this change occurred. Mammals developed from primitive mammal-like evolution of man essay during the Triassic Period, some million years ago.
After the terminal Cretaceous extinction 65 million years ago eliminated the dinosaurs, mammals as one of the surviving groups, underwent an adaptive radiation during the Tertiary Period. The major orders of mammals developed at this time, including the Primates to which humans belong. Other primates include the tarsiers, lemurs, gibbons, evolution of man essay, monkeys, and apes. Although we have significant differences from other primates, we share an evolutionary history that includes traits such as opposable thumbs, stereoscopic vision, evolution of man essay, larger brains, and nails replacing claws.
Primates are relatively unspecialized mammals- they have no wings, still have all four limbs, cannot run very fast, have generally weak teeth, and lack armor or thick protective hides. However, the combination of primate adaptations that include larger brains, tool use, social structure, stereoscopic color vision, highly developed forelimbs and hands, evolution of man essay teeth, and upright posture, place them among the most advanced mammals.
Approximately 20 million years ago central and east Africa was densely forested. Climatic changes resulting from plate tectonic movements and episodes of global cooling about 15 million years ago caused a replacement of the forest by a drier-adapted savanna mixed with open areas of forest.
Primates have modifications to their ulna and radius bones of the lower arm allowing them to turn their hand without turning their elbow. Many primates can also swivel or turn their arms at the shoulder.
These two adaptations offer advantages to life in the trees. Primates have five digits on their forelimbs, evolution of man essay. They are able to grasp objects with their forelimbs in what is known as a prehensile movement. A second modification makes one of the digits opposable, allowing the tips of the fingers and thumb to touch.
Placement of the eyes on the front of the head increases depth perception, an advantageous trait in tree-dwelling primates. Changes in the location of rods and cones in the eye adapted primates for color vision as well as peripheral vision in dim light. Upright posture allows a primate to view its surroundings as well as to use its hands for some other task.
Hominids, the lineage leading to humans, had changes in the shape and size of their pelvis, femur, and knees that allowed bipedalism walking on two legs. The change from quadruped to biped happened in stages, culminating in humans, who can walk or run on two evolution of man essay. Several trends of primate evolution are evident in the teeth and jaw.
First, change in the geometry of the jaw reduced the snout into a flat face. Second, changes in tooth arrangement and numbers increased the efficiency of those teeth for grinding food. Third, about 1. Essay 2. Origin of Apes and Hominids: The fossil record indicates primates evolved about approximately 30 million years ago in Africa.
One branch of primates evolved into the Old and New World Monkeys, the other into evolution of man essay hominoids the line of descent common to both apes and man. Fossil hominoids occur in Africa during the Miocene epoch of the Tertiary period. They gave rise to an array of species in response to major climate fluxes in their habitats.
However, the nature of those habitats leads to an obscuration of the line that leads to humans the hominids. Until a few years ago, the ramapiths were thought to have given rise to the hominids. We now consider ramapiths ancestral to the orangutang. The hominid line arose from some as-yet-unknown ancestor. Lacking fossil evidence, biochemical and DNA evidence suggests a split of the hominid from hominoid line about 6 to 8 million years ago. Australopithecus afarensis, the first of the human-like evolution of man essay we know of, first appeared about 3.
This species had a combination of human bipedalism and apelike features short legs and relatively long arms. The arm bones were curved evolution of man essay chimps, but the elbows were more human-like. Scientists speculate that A. afarensis spent some time climbing trees, as well as on the ground. Australopithecus ramidus is an older species, about 4, evolution of man essay.
The relationship between the two species remains to be solved. The role of A. afarensis as the stem from which the other hominids arose is in some dispute. About 2 million years ago, after a long million year period of little change, as many as six hominid species evolved in response to climate changes associated with the beginning of the Ice Age. Two groups developed- the australopithecines, generally smaller brained and not users of tools; and the line that led to genus Homo, larger brained and makers and users of tools.
The australopithecines died out 1 million years ago; Homo, despite their best efforts atomic weapons, pollution is still here! With an incomplete fossil record, australopithecines, at least the smaller form, A, evolution of man essay. africanus, was thought ancestral to Homo. Recent discoveries however have caused a reevaluation of that hypothesis.
One pattern is sure, human traits evolved at different rates and at different times, in a mosaic- some features skeletal, dietary establishing themselves quickly, others developing later tool making, language, use of fire.
A cluster of species developed about Homo had a larger brain and a differently shaped skull and teeth than the australopithecines. About 1. Soon after its origin 1.
Homo erectus differed from early species of Homo in having a larger brain size, flatter face, and prominent brow ridges. Homo erectus is similar to modern humans in size, but has some differences in the shape of the skull, a receding chin, brow ridges, and differences in teeth. Provide a prolonged period of growth and maturation after birth Betweenandevolution of man essay, evolution of man essay ago, the world population of an estimated 1 million Homo erectus disappeared, evolution of man essay, replaced by a new species, Homo sapiens.
How, when evolution of man essay where this new species arose and how it evolution of man essay its predecessor remain in doubt. Answering those questions has become a multidisciplinary task. The Out-of-Africa Hypothesis proposes that some H.
erectus remained in Africa and continued to evolve into H. sapiens, and left Africa about , years ago. From a single evolution of man essay, H. sapiens replaced all populations of H. Human populations today are thus all descended from a single speciation event in Africa and should display a high degree of genetic similarity.
Support for this hypothesis comes from DNA studies of mitochondria- since African populations display the greatest diversity of mitochondrial DNA, modern humans have been in Africa longer than they have been elsewhere. Calculations suggest all modern humans are descended from a population of African H, evolution of man essay.
sapiens numbering as few as 10, The Regional Continuity Hypothesis suggests that regional populations of H. erectus evolved into H. sapiens through interbreeding between the various populations. Evidence from the fossil record and genetic studies supports this idea. The accuracy of the molecular clock, so key to the out-of-Africa hypothesis, has recently been questioned, evolution of man essay. Recent studies on the Y-chromosome seem to weaken the regional continuity hypothesis by indicating a single point-of-origin for our species someyears ago.
Continued study will no doubt reveal new evidence and undoubtedly new hypotheses will arise. It is a task for all of us to weigh the evidence critically and reach a supportable conclusion, whether we are scientists or not.
The evolutionary history of the primates can be traced back for some 85 million years, as one of the oldest of all surviving placental mammal groups. Most paleontologists consider that primates share a common ancestor with the bats, another extremely ancient lineage, and that this ancestor probably lived during the late Cretaceous, together with the last dinosaurs. The oldest known primates come from North America, but they were widespread in Eurasia and Africa as well, during the tropical conditions of the Paleocene and Eocene.
With the beginning of modern climates, marked by the formation of the first Antarctic ice in the early Oligocene around 40 million years ago, primates went extinct everywhere but Africa and southern Asia. One such primate from this time was Notharctus. Fossil evidence found in Germany 20 years ago was determined to be about It suggests that the primate lineage of the great apes first appeared in Eurasia and not Africa.
Evolution of man essay discoveries suggest that the early ancestors of the hominids the family of great apes and humans migrated to Eurasia from Africa about 17 million years ago, just before these two continents were cut off from each other by an expansion of the Mediterranean Sea.
These primates flourished in Eurasia and that their lineage leading to the African apes and humans —Dryopithecus—migrated south evolution of man essay Europe or Western Asia into Africa.
The Story of Early Man For Kids - Periwinkle
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The Evolution of Humans The evolution of humans was (and is) a very important time. The first being of evolution was Australopithecus Afarensis or “Lucy”. Then we moved on to Homo erectus and Homo Neanderthal. When the weather got hotter, we were Homo Sapiens Sapiens and finally, the modern man. This evolution did not happen overnight One way man has evolved over time is the brain. One of the earliest human to be found was during the Homo habilis period - million years ago (Mcnamme, ,p) Researchers found that humans in this era had a brain capacity between mL Evolution is the theory proposed by Charles Darwin and argues that organisms change physically over time. Part of Darwin’s theory of evolution is the idea of natural selection. Darwin also stated that organisms must have a common ancestor. The theory of human evolution is that humans evolved
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