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http://dsc.discovery.com/earth/slideshows/rapid-evolution/index-06.html

EVOLUTION AND THE ORIGIN OF LIFE ON EARTH. BY LIAM GRINTON. http://dsc.discovery.com/earth/slideshows/rapid-evolution/index-06.html. MY OBJECTIVES. Where did we come from? What is evolution, both as a concept and a process? What is a species? What is extinction, and its role. .

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  1. EVOLUTION AND THE ORIGIN OF LIFE ON EARTH BY LIAM GRINTON http://dsc.discovery.com/earth/slideshows/rapid-evolution/index-06.html

  2. MY OBJECTIVES • Where did we come from? • What is evolution, both as a concept and a process? • What is a species? • What is extinction, and its role.

  3. What is a species? • A species is a “taxonomic group whose members can interbreed.” (1) • “the major subdivision of a genus or subgenus, regarded as the basic category of biological classification, composed of related individuals that resemble one another, are able to breed among themselves, but are not able to breed with members of another species.” (2) • 1). wordnetweb.princeton.edu/perl/webwnw • 2). http://dictionary.reference.com/browse/species

  4. What is a species? A species is the most specific title that can be given to an organism and designates it as a part of a group of similar individuals http://api.ning.com/files/QhfHPzCpVsNLbRRSfx*k01LhvRfeLYFQDI-INs1jPO66HD0K9Y3OlOF*2IM8RATO2HgUZ4zyKEvdnUK08xT8IbdWj7wnLY4k/138599_KPCOFGS.jpg

  5. The Role of Extinction • Extinction can act as a form of large scale natural selection by wiping out an entire unfit species at the same time through some natural event, while the fit survive. It is a cross between genetic drift and natural selection in the sense that it may affect a large population, but is not removing them at random. Extinction may also occur through environmental factors such as loss of habitat.

  6. The Role of Extinction • no longer active; extinguished • When the last member of a species dies, the species is considered extinct. • When a species dies out, an imbalance is often created due to the fact that that organism is a vital part of a web. That web depends on all organisms

  7. The Role of Extinction • “doing their part” to sustain an ecosystem. The extinction may cause the suffering of another species, or cause it to thrive, again often causing an imbalance.

  8. Evolution • Evolution is both a concept and a process. The fundamental mechanisms that make evolution possible are Natural Selection, Genetic drift, and Mutation. All of these concepts work together to facilitate the process that we know as evolution. All of these processes work on individual species or individuals.

  9. Genetic drift • Genetic drift is very similar to Natural selection, which I will cover after this. Genetic drift is when the gene pool of a population of organisms is affected by an event in which some members of the species are made unfit to reproduce, or are killed by a random occurrence. “Genetic drift does not work to produce adaptations” (2.5) 2.5). http://evolution.berkeley.edu/evosite/evo101/IIIDGeneticdrift.shtml

  10. Darwin and the Theory of Evolution(natural selection) • The common belief before the discovery of evolution is the theory of creationism. Creationism is a concept in which all species have been placed on earth by god. These species never change and are perfect. This belief is starting to die out due to the theory and proven process of evolution.

  11. Darwin and the Theory of Evolution(natural selection) • Charles Darwin was a naturalist in the 1800’s. He discovered evolution- (developed the theory)- after his trip to the Galapagos islands. He found that many of the species in the Galapagos -for example finches and tortoises had traits very different to those in other parts of the world.

  12. Darwin and the Theory of Evolution(natural selection) • After returning from the Galapagos, Darwin found that the numerous species of birds that he had collected from the different islands were, in fact, one species- but with variations. This was extremely intriguing. He came to the conclusion that species change.

  13. Darwin and the Theory of Evolution(natural selection) • Charles Darwin not only discovered the breakthrough of evolution, but he gave reasons why it was legitimate as opposed to the common view of creationism. His reasoning was that it was improbable that god would bother to created different kinds of finches for each Galapagos island. Instead there must be some practical reason.

  14. Darwin and the Theory of Evolution(natural selection) Animals were savage creatures fighting for survival. Through the evolutionary process the beaks of the finches had adapted to the food on specific islands giving them an advantage to survive.

  15. Darwin and the Theory of Evolution(natural selection) • Short, strong beaks were efficient for crushing and eating nuts and seeds, whereas long, probing beaks were good for eating the insides of flowers. This is when Darwin coined the term for the process of “natural selection”. This new theory of “natural selection” was an explanation of how species could change.

  16. Darwin and the Theory of Evolution(natural selection) • Only the fittest survive, they breed, only the fittest of their offspring survive and so on until the resulting individuals are so different that they can no longer interbreed with the original organisms. This is the point at which a new species has been created.(3) 3). http://www.pbs.org/wgbh/nova/evolution/darwin-never-knew.html

  17. What discoveries we have added to Darwin’s theory. • MUTATION Mutation is one of the driving processes of natural selection, Darwin knew that evolution happened he just didn’t know exactly how. The answer is deoxyribonucleic acid. When a child is conceived, it gets half of its DNA from the mother and the other half from the father.

  18. What discoveries we have added to Darwin’s theory. • MUTATION • This is why each person looks somewhat like their mother and somewhat like their father. This would not happen however, if there were no such thing as mutation. Mutation is when a part of the DNA molecule contains an error or distortion.

  19. What discoveries we have added to Darwin’s theory. • MUTATION • Mutation generally happens when our bodies copy our DNA and our cells divide. When our cells mutate, it is rarely felt, however, when mutation occurs in the cells that we pass down to our offspring, big changes may occur.

  20. What discoveries we have added to Darwin’s theory. • MUTATION • If, through mutation, an organism derives a certain trait, it may favor or inconvenience that organism to the forces of Natural Selection. This could result in that organism either passing on or not passing on its genetic traits through reproduction and staying in the population’s gene pool.

  21. What discoveries we have added to Darwin’s theory. • MUTATION • Because Natural Selection happens in a specific area to a certain population, the traits may only be visible in certain places, such as the individual islands of the Galapagos.(4) 4.) http://www.pbs.org/wgbh/nova/evolution/darwin-never-knew.html

  22. Where did we come from?(a brief history of human evolution) • There are many views as to where we come from, including creationism. In science the most accepted theory, and that withstanding the concept of Darwinian evolution is that life started many millions of years ago. • Likely is the fact that the first form of life was a simple nucleic acid molecule, nowhere near as complex as DNA, that acted as a building plan and facilitated a reproducible result. We assume that this might have been the first, crude form of cell division and the reproduction of a life form. The first form of life might not look particularly “alive” but more like a replicating molecule.

  23. Where did we come from?(a brief history of human evolution) • From this theory on, not much is known about the exact progression of life to the modern day diverse population of beings. We know, however that the first life form must have been simple enough to be created by the natural processes on earth. For this, a certain recipe of materials must have been at hand on the planet. This is why earth has life and no other planets in the solar system have life. Most of the beings on earth have about the same proportions of

  24. Where did we come from?(a brief history of human evolution) • Carbon, oxygen, and hydrogen, supporting this theory. Through evolution, we know that we got here from those individual molecules, however there is a lot missing in between, and dinosaurs and early bacteria are evolutionary newcomers in comparison.(5) from this first living molecule and 3.5 billion (5.5) years worth of evolution have developed the tree of life to what it is today. All land animals are the descendants of a fish like animal that came to land. this Tiktaalikroseaeemerged from the water 375 million years ago.(6) 5). http://www.pbs.org/wgbh/nova/evolution/how-did-life-begin.html 5.5). http://rainbow.ldeo.columbia.edu/courses/v1001/7.html 6). http://news.uchicago.edu/news.php?asset_id=1458

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