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The Theory of Evolution

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The Theory of Evolution

  1. 1. Presentor: Algine B. Casanova
  2. 2. What is an Evolution?
  3. 3. Mirriam-Webster Dictionary: Evolution ○ A process of continuous change from a lower, simpler, or worse to a higher, more complex, or better state : growth ○ The historical development of a biological group ( as a race or species ) phylogeny ○ A theory that the various types of animals and plants have their origin in other pre-existing types and that the distinguishable differences are due to modifications in successive generations
  4. 4. Evolution is the change in the inherited characteristics of biological populations over successive generations. It is a processes that give rise to diversity at every level of biological organization, including species, individual organisms and molecules such as DNA and proteins.
  5. 5. Topics:  1 Introduction  1.1 History of evolutionary thought  2 Heredity  3 Variation  3.1 Mutation  3.2 Gene flow  3.3 Natural selection  3.4 Adaptation  3.5 Extinction
  6. 6.  4 History of Human Origin  4.1 Human Ancestor ○a. Australopithecines ○b. The Genus Homo 3 Periods -Early, Middle and Late ○c. Homo Sapiens ○d. Modern Man  5 Evolutionism vs. Creationism
  7. 7. First Question:  He was the first scientist to formulate a scientific argument for the theory of evolution by means of natural selection.
  8. 8. Charles Darwin
  9. 9. Fun Fact About DARWIN: ( Stinky feet )
  10. 10. Don’t you know that…. At age of 12, Darwin confessed in a letter, that he only washed his feet once a month at school, due to a lack of anything with which to wash.
  11. 11. Introduction:  All life on Earth is descended from a last universal ancestor that lived approximately 3.8 billion years ago.  Repeated speciation and the divergence of life can be inferred from shared sets of biochemical and morphological traits, or by shared DNA sequences.
  12. 12.  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.
  13. 13. 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 inferred from threefacts about populations:  1) more offspring are produced than can possibly survive,  2) traits vary among individuals, leading to different rates of survival and reproduction, and  3) trait differences are heritable.
  14. 14. 1.1 History Of Evolutionary Thought  Anaximander and Empedocles- they are the one who proposed that one type of animal could descend from an animal of another type during the pre-Socratic Period.  Aristotle- understood all natural things, not only living things, as being imperfect actualizations of different fixed natural possibilities, known as "forms", "ideas", or (in Latin translations) "species".
  15. 15.  John Ray used one of the previously more general terms for fixed natural types, "species", to apply to animal and plant types, but he strictly identified each type of living thing as a species, and proposed that each species can be defined by the features that perpetuate themselves each generation.  The biological classification introduced by Carolus Linnaeus in 1735 also viewed species as fixed according to a divine plan.
  16. 16.  In 1842 Charles Darwin penned his first sketch of what became On the Origin of Species.  Maupertuis wrote in 1751 of natural modifications occurring during reproduction and accumulating over many generations to produce new species.  Lamarck- "transmutation" theory of 1809, which viewd spontaneous generation continually producing simple forms of life developed greater complexity in parallel lineages with an inherent progressive tendency, and that on a local level these lineages adapted to the environment by inheriting changes caused by use or disuse in parents. (Lamarckism)
  17. 17. Darwin was partly influenced by An Essay on the Principle of Population and noted that population growth would lead to a "struggle for existence" where favorable variations could prevail as others perished. 2nd Question: Who wrote that essay? Thomas Robert Malthus
  18. 18.  Darwin was developing his theory of "natural selection" from 1838 onwards until Alfred Russel Wallace sent him a similar theory in 1858. Both men presented their separate papers to the Linnean Society of London.  Thomas Henry Huxley applied Darwin's ideas to humans, using paleontology and comparative anatomy to provide strong evidence that humans and apes shared a common ancestry.
  19. 19.  Gregor Mendel reported that traits were inherited in a predictable manner through the independent assortment and segregation of elements (later known as genes). Mendel's laws of inheritance eventually supplanted most of Darwin's pangenesis theory.  . Hugo de Vries connected Darwin's pangenesis theory to Weismann's germ/soma cell distinction and proposed that Darwin's pangenes were concentrated in the cell nucleus and when expressed they could move into the cytoplasm to change the cells structure.
  20. 20.  De Vries developed a mutation theory that led to a temporary rift between those who accepted Darwinian evolution and biometricians who allied with de Vries.  In the 1920s and 1930s a modern evolutionary synthesis connected natural selection, mutation theory, and Mendelian inheritance into a unified theory that applied generally to any branch of biology.
  21. 21. 3rd Question: The branch of Biology that studies genes and heredity. GENETICS
  22. 22. H E R E D I T Y
  23. 23. What is Heredity?
  24. 24. Heredity The sum of the characteristics and potentialities genetically derived from one’s ancestors The transmission of such qualities from ancestor to descendant through the genes
  25. 25. DNA structure. Bases are in the centre, surrounded by phosphate–sugar chains in a double helix.
  26. 26. What is its connection to evolution?
  27. 27.  Evolution in organisms occurs through changes in heritable traits – particular characteristics of an organism. In humans, for example, eye colour is an inherited characteristic and an individual might inherit the "brown-eye trait" from one of their parents.  Genotype- traits are controlled by genes and the complete set of genes within an organism's genome.  Phenotype- the complete set of observable traits that make up the structure and behaviour of an organism.  Heritable traits are passed from one generation to the next via DNA, a molecule that encodes genetic information.[53] DNA is a long polymer composed of four types of bases
  28. 28. 4th Question Portion/s of a DNA molecule that specify a single functional unit. Gene/s
  29. 29. VARIATION White peppered moth Black morph in peppered moth evolution
  30. 30. Variation: Divergence in the structural or functional characteristics of an organism from the species or population norm or average.
  31. 31. How does it affect Evolution?
  32. 32. An individual organism's phenotype results from both its genotype and the influence from the environment it has lived in. A substantial part of the variation in phenotypes in a population is caused by the differences between their genotypes. The modern evolutionary synthesis defines evolution as the change over time in this genetic variation.
  33. 33. 5th Question: Variation disappears when a new allele reaches the point of _____ — when it either disappears from the population or replaces the ancestral allele entirely. a. Fixation b. Combination c. Alteration d. Separation a.
  34. 34. MUTATION
  35. 35. Mutation: A relatively permanent change in hereditary material involving either a physical change in chromosomes relations or a biochemical change in the codons that make up genes Mutations are changes in the DNA sequence of a cell's genome.
  36. 36.  Mutations can involve large sections of a chromosome becoming duplicated (usually by genetic recombination), which can introduce extra copies of a gene into a genome.[71] Extra copies of genes are a major source of the raw material needed for new genes to evolve.[72] This is important because most new genes evolve within gene families from pre-existing genes that share common ancestors.[73] For example, the human eye uses four genes to make structures that sense light: three for colour vision and one for night vision; all four are descended from a single ancestral gene.
  37. 37. 6th Question: ______ are large enzymes that produces antibiotics; they contain up to one hundred independent domains that each domains catalyzed one step in the overall process, like a step in an assembly line. a. Polytetide Synthase b. Polymortide Synthase c. Poliketide Synthase d. Polimetide Synthase c
  38. 38. Gene Flow:  Is the exchange of genes between populations and between species. It can therefore be a source of variation that is new to a population or to a species. Gene flow can be caused by the movement of individuals between separate populations of organisms, as might be caused by the movement of mice between inland and coastal populations, or the movement of pollen between heavy metal tolerant and heavy metal sensitive populations of grasses.
  39. 39. Natural Selection by: Charles Darwin
  40. 40. Evolution by means of natural selection is the process by which genetic mutations that enhance reproduction become and remain more common in successive generations of a population.
  41. 41. It has often been called a "self- evident" mechanism because it necessarily follows from three simple facts: 1. Heritable variation exists within populations of organisms. 2. Organisms produce more progeny than can survive. 3. These offspring vary in their ability to survive and reproduce.
  42. 42.  The central concept of natural selection is the evolutionary fitness of an organism. Fitness is measured by an organism's ability to survive and reproduce, which determines the size of its genetic contribution to the next generation. However, fitness is not the same as the total number of offspring: instead fitness is indicated by the proportion of subsequent generations that carry an organism's genes.
  43. 43. ADAPTATION
  44. 44. 7th Question: An aspect of the developmental pattern of the organism which enables or enhances the probability of that organism to survive and reproduce. a. Adaptedness b. Adaptive traits c. Adaptation d. Adapting b.
  45. 45. Adaptation is the process that makes organisms better suited to their habitat. Also, the term adaptation may refer to a trait that is important for an organism's survival.
  46. 46.  The following definitions are due to Theodosius Dobzhansky. 1. Adaptation is the evolutionary process whereby an organism becomes better able to live in its habitat or habitats.[161] 2. Adaptedness is the state of being adapted: the degree to which an organism is able to live and reproduce in a given set of habitats.[162] 3. An adaptive trait is an aspect of the developmental pattern of the organism which enables or enhances the probability of that organism surviving and reproducing.[163]
  47. 47. Extinction Tyrannosaurus rex. Non-avian dinosaurs died out in the Cretaceous–Paleogene extinction event at the end of the Cretaceous period.
  48. 48.  Extinction is the disappearance of an entire species. Extinction is not an unusual event, as species regularly appear through speciation and disappear through extinction. Nearly all animal and plant species that have lived on Earth are now extinct, and extinction appears to be the ultimate fate of all species.These extinctions have happened continuously throughout the history of life, although the rate of extinction spikes in occasional mass extinction events.
  49. 49. 8th Question: Human activities are now the primary cause of the ongoing extinction event; what event or phenomenon may further accelerate extinction in the future? Global Warming
  50. 50. History Of Human Origin
  51. 51. Do you believe that WE humans really descended from APES??
  52. 52. Since scientists developed the ability to decode the genome and compare the genetic makeup of species, some people have been stunned to learn that about 98.5% of the genes in people and chimpanzees are identical.
  53. 53. Humans share a common ancestor with modern African apes (i.e., gorillas and chimpanzees), making us very, very distant cousins. We are therefore related to these other living primates, but WE DID NOT DESCEND FROM THEM.
  54. 54. Modern humans differ from apes in many significant ways.
  55. 55. 1. Human brains are larger and more complex.
  56. 56. 2. Humans have elaborate forms of communication and culture.
  57. 57. 3. Humans habitually walk upright, can manipulate very small objects, and can speak.
  58. 58. 1.1 Human Ancestor  Most scientists believe our common ancestor existed 5 to 8 million years ago. Then two species broke off into separate lineages, one ultimately evolving into gorillas and chimps, the other evolving into early humans called hominids. In the millions of years that followed, at least a dozen different species of humanlike creatures have existed, reflected in the fossil discoveries of paleoanthropologists, although many of these species are close relatives but not actual ancestors of modern humans.
  59. 59. 9th Question: ______ are the remains or impressions of living things hardened in rock. FOSSILS
  60. 60. 4.1 Human Ancestor
  61. 61.  The earliest humans were found in Africa, which is where much of human evolution occurred. The fossils of these EARLY HOMINIDS, which lived 2 to 6 million years ago, all come from that continent. Most scientists believe early humans migrated out of Africa into Asia between 2 million and 1.7 million years ago, entering Europe some time within the past 1 million years. What follows are some highlights of the early human species that have been identified by scientists to date.
  62. 62. Australopithecines The name australopithecine means “southern ape,” in reference to South Africa where the first known fossils were found. Many more australopith fossils have been found in the Great Rift Valley in eastern Africa, in countries including Ethiopia, Tanzania, Kenya, and Chad.
  63. 63. Trivia!! The best-known australopith specimen is “Lucy,” the partial skeleton of a female discovered in 1974 in Hadar, Ethiopia. Lucy belongs to a species, Australopithicus afarensis, which thrived in eastern Africa between 3.9 million and 3 million years ago. Scientists have found several hundred A. afarensis fossils in Hadar. Lucy lived 3.2 million years ago.
  64. 64. By about 2.7 million years ago, so- called robust australopiths (in contrast to the earlier, gracile forms) had evolved, with wide molars and premolars and a facial structure that indicate that these robust australopiths chewed their food, primarily tough, fibrous plants, powerfully and for long periods.
  65. 65. The Genus Homo  The genus Homo first evolved at least 2.3 million to 2.5 million years ago. The most significant difference between members of this genus and australopiths, with which they overlapped, was their significantly larger brains (about 30 percent larger, though still small compared to modern humans).
  66. 66. 3 periods of Homo Evolution  1. Early Period Species of early Homo, among them Homo habilis, resembled australopiths in many distinct ways, but they had smaller teeth and jaws, more modern-looking feet, and hands capable of making tools. They probably lived from between 2.5 or 2.3 million and 1.6 million years ago.
  67. 67.  2. Middle Period The middle Homo species, including Homo erectus, evolved anatomically to be more similar to modern humans but their brains were relatively small (though bigger than australopiths). They probably overlapped with earlier Homo species, as they developed perhaps between 2 million and 1.8 million years ago.
  68. 68. 3. Late Period The final transition, from the middle to late periods, happened about 200,000 years ago. Late Homo species, including Neanderthals and Homo sapiens, evolved large and complex brains, leading eventually to language, and developed culture as an increasingly important aspect of human life.
  69. 69. Homo Sapiens  Scientists have dated the oldest known fossils with skeletal features typical of modern humans from 195,000 years ago. Early anatomically modern Homo sapiens fossils have come from sites in Sudan, Ethiopia, South Africa, and Israel. Many scientists have therefore concluded that modern Homo sapiens evolved in Africa and began spreading to other parts of the world 90,000 years ago or a little earlier, although whether, how, why, and when this happened is still in dispute. And it was not until about 40,000 years ago that anatomically modern humans, HOMO SAPIENS SAPIENS, emerged.
  70. 70. Modern Humans
  71. 71. What we are today. Walking straight and doing a lot of tasks. We humans are said to be the highest form of animals because we have brain that we can use for thinking.
  72. 72. 10th Question: The only thing that Humans can do but Animals cannot? To ask Questions
  73. 73. Evolution vs. Creationis m Science vs. Religion
  74. 74. Which is really true? The THEORY? Or the DEVINE TEACHING?
  75. 75. What is a THEORY?
  76. 76. In science, a theory is an overarching explanation used to describe some aspect of the natural world that is supported by overwhelming evidence.
  77. 77. What is RELIGION?
  78. 78. A system A belief that God or other supernatural exist A commitment A worship A belief that all the things in the world is created by one and only God.
  79. 79. FUTUR E
  80. 80. EVOLUTI ON IS A PROCESS
  81. 81. Yesterday until today…
  82. 82. Today Until Tomorrow…
  83. 83. And who knows in the future, this will be the next….
  84. 84. The End….
  85. 85. Thank you! 
  86. 86. Credits to: Rodel Ortega Roden Ortega

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