Evolution
Evolution is the change in the inherited characteristics of biological populations over successive generations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.[1]
Life on Earth originated and then evolved from a universal common ancestor approximately 3.7 billion years ago. Repeated speciation and thedivergence of life can be inferred from shared sets of biochemical and morphological traits, or by shared DNA sequences. These homologous traits and sequences are more similar among species that share a more recent common ancestor, and can be used to reconstruct evolutionary histories, using both existing species and the fossil record. Existing patterns of biodiversity have been shaped both by speciation and by extinction.[2]
Charles Darwin was the first to formulate a scientific argument for the theory of evolution by means of natural selection. Evolution by natural selection is a process that is inferred from three facts about populations: 1) more offspring are produced than can possibly survive, 2) traits vary among individuals, leading to differential rates of survival and reproduction, and 3) trait differences are heritable.[3] Thus, when members of a population die they are replaced by the progeny of parents that were better adapted to survive and reproduce in the environment in which natural selection took place. This process creates and preserves traits that are seemingly fitted for the functional roles they perform.[4] Natural selection is the only known cause ofadaptation, but not the only known cause of evolution. Other, nonadaptive causes of evolution include mutation and genetic drift.[5]
In the early 20th century, genetics was integrated with Darwin's theory of evolution by natural selection through the discipline of population genetics. The importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis and "progress" became obsolete.[6] Scientists continue to study various aspects of evolution by forming and testing hypotheses, constructing scientific theories, using observational data, and performing experiments in both the field and the laboratory. Biologistsagree that descent with modification is one of the most reliably established facts in science.[7] Discoveries in evolutionary biology have made a significant impact not just within the traditional branches of biology, but also in other academic disciplines (e.g., anthropology and psychology) and on society at large.[8][9](http://en.wikipedia.org/wiki/Evolution)
Darwin's Theory of Evolution - The Premise
Darwin's Theory of Evolution is the widely held notion that all life is related and has descended from a common ancestor: the birds and the bananas, the fishes and the flowers -- all related. Darwin's general theory presumes the development of life from non-life and stresses a purely naturalistic (undirected) "descent with modification". That is, complex creatures evolve from more simplistic ancestors naturally over time. In a nutshell, as random genetic mutations occur within an organism's genetic code, the beneficial mutations are preserved because they aid survival -- a process known as "natural selection." These beneficial mutations are passed on to the next generation. Over time, beneficial mutations accumulate and the result is an entirely different organism (not just a variation of the original, but an entirely different creature).
Darwin's Theory of Evolution - Natural SelectionDarwin's Theory of Evolution is the widely held notion that all life is related and has descended from a common ancestor: the birds and the bananas, the fishes and the flowers -- all related. Darwin's general theory presumes the development of life from non-life and stresses a purely naturalistic (undirected) "descent with modification". That is, complex creatures evolve from more simplistic ancestors naturally over time. In a nutshell, as random genetic mutations occur within an organism's genetic code, the beneficial mutations are preserved because they aid survival -- a process known as "natural selection." These beneficial mutations are passed on to the next generation. Over time, beneficial mutations accumulate and the result is an entirely different organism (not just a variation of the original, but an entirely different creature).
While Darwin's Theory of Evolution is a relatively young archetype, the evolutionary worldview itself is as old as antiquity. Ancient Greek philosophers such as Anaximander postulated the development of life from non-life and the evolutionary descent of man from animal. Charles Darwin simply brought something new to the old philosophy -- a plausible mechanism called "natural selection." Natural selection acts to preserve and accumulate minor advantageous genetic mutations. Suppose a member of a species developed a functional advantage (it grew wings and learned to fly). Its offspring would inherit that advantage and pass it on to their offspring. The inferior (disadvantaged) members of the same species would gradually die out, leaving only the superior (advantaged) members of the species. Natural selection is the preservation of a functional advantage that enables a species to compete better in the wild. Natural selection is the naturalistic equivalent to domestic breeding. Over the centuries, human breeders have produced dramatic changes in domestic animal populations by selecting individuals to breed. Breeders eliminate undesirable traits gradually over time. Similarly, natural selection eliminates inferior species gradually over time.
Darwin's Theory of Evolution - Slowly But Surely...
Darwin's Theory of Evolution is a slow gradual process. Darwin wrote, "…Natural selection acts only by taking advantage of slight successive variations; she can never take a great and sudden leap, but must advance by short and sure, though slow steps." [1] Thus, Darwin conceded that, "If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down." [2] Such a complex organ would be known as an "irreducibly complex system". An irreducibly complex system is one composed of multiple parts, all of which are necessary for the system to function. If even one part is missing, the entire system will fail to function. Every individual part is integral. [3] Thus, such a system could not have evolved slowly, piece by piece. The common mousetrap is an everyday non-biological example of irreducible complexity. It is composed of five basic parts: a catch (to hold the bait), a powerful spring, a thin rod called "the hammer," a holding bar to secure the hammer in place, and a platform to mount the trap. If any one of these parts is missing, the mechanism will not work. Each individual part is integral. The mousetrap is irreducibly complex. [4]
Darwin's Theory of Evolution - A Theory In Crisis
Darwin's Theory of Evolution is a theory in crisis in light of the tremendous advances we've made in molecular biology, biochemistry and genetics over the past fifty years. We now know that there are in fact tens of thousands of irreducibly complex systems on the cellular level. Specified complexity pervades the microscopic biological world. Molecular biologist Michael Denton wrote, "Although the tiniest bacterial cells are incredibly small, weighing less than 10-12 grams, each is in effect a veritable micro-miniaturized factory containing thousands of exquisitely designed pieces of intricate molecular machinery, made up altogether of one hundred thousand million atoms, far more complicated than any machinery built by man and absolutely without parallel in the non-living world." [5]
And we don't need a microscope to observe irreducible complexity. The eye, the ear and the heart are all examples of irreducible complexity, though they were not recognized as such in Darwin's day. Nevertheless, Darwin confessed, "To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree." [6]
Footnotes:
- Charles Darwin, "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life," 1859, p. 162.
- Ibid. p. 158.
- Michael Behe, "Darwin's Black Box," 1996.
- "Unlocking the Mystery of Life," documentary by Illustra Media, 2002.
- Michael Denton, "Evolution: A Theory in Crisis," 1986, p. 250.
- Charles Darwin, "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life," 1859, p. 155.( http://www.darwins-theory-of-evolution.com/)
For centuries, people have wondered how the world was created. We may never know how we came to be, but there are many different theories on the subject. From scientists to mathematicians to religious deities all have theories on how the world was created. What theory you choose to believe is up to you.
1. The Mayans
According to the Mayans, there were two people, Tepeu and Gucumatz. They would sit around and think about things and then those things would exist. They thought up the mountains, the earth, the oceans, the sky and the animals and once they did they appeared. They used clay to create people, which would fall apart when they got wet, so they made people at of wood. These people would cause trouble so the God created a flood and wiped them out. They were allowed to start over. This is how the Earth became what it is today.
2. The Scandinavians
According the Scandinavians, there was an emptiness that needed to be filled. There were two Gods, Muspell and Niflhiem. Muspell was the leader of the fiery realm and Niflhiem was the leader of the icy realm. They would plat in this vast open space. Inside the space the air grew mild and once the ice started to melt, Ymir was created. He was an evil God. While Ymir slept, he sweated and brought to life two males and a female frost giant. More ice melted in the time passed and a cow was created. She had plenty of milk to feed Ymir. She would nourish herself by licking the ice blocks. After a few days of licking the ice, she revealed a man who had a son. The son married one of the frost giant’s daughters and they had three sons, who killed Ymir. The blood that flowed from Ymir drowned all the frost giants except for Berglimir and his wife. They took the flesh and bones of Ymir and then created the Earth. While walking along the Earth’s surface Odin, one of the sons of the frost giant, spotted two logs and gave them life, while one of the other brothers gave them brains and feelings and the other gave them hearing and sight. From this man and women all life is created.
3. The Chinese
Chinese believe that in the beginning heaven and Earth were as one. The universe was a big black egg that carried a God, Pan-Gu, inside itself. Pan Gu awoke from a 18 thousand year nap and wanted out of the egg. He took his broad axe and smashed through. The light became the heavens and the heavier parts became the Earth. Pan-Gu stood in between with his head touching the heavens and his feet firmly planted on the Earth. All three would grow at a rate of ten feet per day. After 18 thousand years everything stopped growing. After his passing, he breathe became the wind and the clouds. His voice is the thunder and his eyes became the sun and moon. The mountains were formed from his body and limbs and the rivers and oceans are made of his blood. The fertile soil is from his muscles and the roads are his veins. The flowers and trees are from his skin and body hair, where the stars are from his beard and hair. Pearls and jade are made from his marrow and his sweat is the rain and dew.
4. The Australians
In Australia they believe that the earth was plain and bare in the beginning. There was no light, life or death. The sun, moon, stars and eternal ancestors all slept beneath the Earth. When the ancestors arose, they would walk the earth in human form, animal form, plant form or a combination of the forms. There were two people that formed out of nothing and upon their walks across the Earth’s surface they would come upon some half finished plants, animals and humans. They would then carve heads, bodies and limbs from bundles of plants. This is how people were formed amongst the Earth’s surface. After the work of human creation was finished the ancestors went back to sleep. They either went back under the Earth or they stayed here in the form of plants and animals. They left sacred trails, which can be seen in the forms watering holes, rocks and trees.
5. The Apache Indians
They believed that in the beginning there was nothing. Suddenly, there was a thin disk with a man inside. After awaking from his nap he looked up and light appeared, looking down he created a sea of light, to the east he created the streaks of dawn and to the west the colorful streaks of dusk. After creating all the light, he wiped his hands together and then thrust them in a downward motion. A girl on a cloud appeared. He asked her where she was going and she did not answer. She asked him where he was from and he said from the east. She asked where the earth was and he asked where the sky was. He sang four times, which is the lucky number to the Apache Indians that he was thinking of what to create next. He flung his hands wide open and then appeared the sun God. He then dropped his hands and then a small boy appeared. All four Gods where now present and they all shook hands, mixing their sweat together and then he sang about making the Earth again four times. After rubbing his hands together, a brown ball appeared. He kicked it and it expanded, the girl kicked it and it did the same, the sun God and the boy both took turns and the ball continued to expand. He then told the wind to go inside and blow it up. The Creator had created more Gods to look over things on Earth. He had created workers to help with the building of Earth. Once he seen work was done, then he disappeared leaving the works to create the world’s population.
Author: Harmony Stalter — Copyrighted © roadtickle.com(http://roadtickle.com/5-interesting-theories-on-world-creation/)
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