Evolution

1. Evolution The quick view (which is opposite of how evolution works, so it’s kind of ironic eh?)

2. Science vs. Religion • What is science based on? • Science is based on OBSERVABLE evidence. • What is religion based on? • Religion is based on FAITH. • By definition, faith is something that is not observable. • Since they are 2 different “fields,” they aren’t really competing with each other

3. Religious Scientists? • My religion consists of a humble admiration of the illimitable superior spirit who reveals himself in the slight details we are able to perceive with our frail and feeble mind. • Albert Einstein (1879 - 1955) • Science without religion is lame, religion without science is blind. • Albert Einstein (1879 - 1955), "Science, Philosophy and Religion: a Symposium", 1941 • Not only does God play dice, but... he sometimes throws them where they cannot be seen. • Stephen Hawking

4. “Evolution is a Theory” • True, but to paraphrase Carl Sagan: • Creationists think that a theory is something that you made up while drunk one night. • Theory Defined: “scientific principle to explain phenomena: a set of facts, propositions, or principles analyzed in their relation to one another and used, especially in science, to explain phenomena” • MSN Encarta, http://encarta.msn.com/dictionary_/theory.html • Evolution is as much a theory as gravity is

5. The Fossil Record doesn’t support evolution – there are too many “missing links” Arguments based on the fossil record as a “problem” for evolution backfired “So many intermediate forms have been discovered between fish and amphibians, between amphibians and reptiles, between reptiles and mammals, and along the primate lines of descent that it often is difficult to identify categorically when the transition occurs from one to another particular species.” National Academy of Sciences, 1999

6. ? ? ? ? Land Mammal MissingIntermediates

8. Reconstructions of representative Eocene cetaceans. Clockwise from top: a beached Dorudon (Dorudontidae), Ambulocetus (Ambulocetidae), Pakicetus (Pakicetidae), Kutchicetus (Remingtonocetidae), and Rodhocetus (Protocetidae). These cetaceans are shown together for comparison, but they were not contemporaries and lived in different environments. Artwork by Carl Buell.

10. Comparative Genome Evidence for Human Evolution is Decisive “More than a century ago Darwin and Huxley posited that humans share recent common ancestors with the African great apes. Modern molecular studies have spectacularly confirmed this prediction and have refined the relationships, showing that the common chimpanzee (Pan troglodytes) and bonobo (Pan paniscus) are our closest living evolutionary relatives.”

11. Testing the Evolutionary Hypothesis of Common Ancestry Chromosome Numbers in the great apes: human (Homo) 46chimpanzee (Pan) 48gorilla (Gorilla) 48orangutan (Pogo) 48 Testable prediction: If these organisms share common ancestry, the human genome must contain a fused chromosome.

12. Fusion Homo sapiens Centromere #1 Telomere sequences Centromere #2 Ancestral Chromosomes Chromosome Numbers in the great apes (Hominidae): human (Homo) 46chimpanzee (Pan) 48gorilla (Gorilla) 48orangutan (Pogo) 48 Centromere Telomere Testable prediction: The marks of that fusion must appear in one of the human chromosomes.

13. Human Chromosome #2 shows the exact point at which this fusion took place “Chromosome 2 is unique to the human lineage of evolution, having emerged as a result of head-to-head fusion of two acrocentric chromosomes that remained separate in other primates. The precise fusion site has been located in 2q13–2q14.1 (ref. 2; hg 16:114455823 – 114455838), where our analysis confirmed the presence of multiple subtelomeric duplications to chromosomes 1, 5, 8, 9, 10, 12, 19, 21 and 22 (Fig. 3; Supplementary Fig. 3a, region A). During the formation of human chromosome 2, one of the two centromeres became inactivated (2q21, which corresponds to the centromere from chimp chromosome 13) and the centromeric structure quickly deterioriated (42).” Homo sapiens Inactivated centromere(Pan #13) Telomere sequences Active centromere(Pan #12) Hillier et al (2005) “Generation and Annotation of the DNA sequences of human chromosomes 2 and 4,” Nature 434: 724-731.

14. It Means Continuing Controversy. Why? The question: “What about Evolution” quickly becomes “What about something else…”

15. What’s behind this is a deliberate strategy to put science & religion at odds: “The objective [of the Wedge Strategy] is to convince people that Darwinism is inherently atheistic, thus shifting the debate from creationism vs. evolution to the existence of God vs. the non-existence of God. From there people are introduced to ‘the truth’ of the Bible and then ‘the question of sin’ and finally ‘introduced to Jesus.’” • Church & State magazine, April 1999 •

16. “Intelligent design is just the Logos theology of John’s Gospel restated in the idiom of information theory.” — William Dembski, 1999 “My colleagues and I speak of ‘theistic realism’ — or sometimes ‘mere creation’— as the defining concept of our movement. This means that we affirm that God is objectively real as Creator.” — Phillip Johnson 1996

17. The Science / Faith Conflict is often the First Issue Raised in Opposition to Evolution What about God PBS Movie The Colbert Report (click here first) http://www.brown.edu/Courses/BI0020_Miller/talks/colbert-miller.mov The Colbert Report January 12, 2006

18. In a famous article, "Nothing in biology makes sense except in the light of evolution" (Am. Biol. Teach.35, 125–129; 1973), Dobzhansky described his religious beliefs: "It is wrong to hold creation and evolution as mutually exclusive alternatives. I am a creationist and an evolutionist. Evolution is God's, or Nature's, method of Creation." In contrast to modern creationists, Dobzhansky accepted macroevolution and the documented age of Earth. He argued that "the Creator has created the living world not by caprice (supernatural fiat) but by evolution propelled by natural selection".

20. Does this mean that the Bible should be read as a scientific textbook? “Even a non-Christian knows something about the earth, the heavens, … the kinds of animals, shrubs, stones, and so forth, and this knowledge he holds to as being certain from reason and experience. Now it is a disgraceful and dangerous thing for an infidel to hear a Christian, presumably giving the meaning of Holy Scripture, talking nonsense on these topics; and we should take all means to prevent such an embarassing situation, in which people show up vast ignorance in a Christian and laugh it to scorn.” St. Augustine, 411 AD On the Literal Meaning of Genesis, 1:19

21. 63. According to the widely accepted scientific account, the universe erupted 15 billion years ago in an explosion called the “Big Bang” and has been expanding and cooling ever since. Later there gradually emerged the conditions necessary for the formation of atoms, still later the condensation of galaxies and stars, and about 10 billion years later the formation of planets. In our own solar system and on earth (formed about 4.5 billion years ago), the conditions have been favorable to the emergence of life. While there is little consensus among scientists about how the origin of this first microscopic life is to be explained, there is general agreement among them that the first organism dwelt on this planet about 3.5-4 billion years ago. Since it has been demonstrated that all living organisms on earth are genetically related, it is virtually certain that all living organisms have descended from this first organism. 69. The current scientific debate about the mechanisms at work in evolution requires theological comment insofar as it sometimes implies a misunderstanding of the nature of divine causality. Many neo-Darwinian scientists, as well as some of their critics, have concluded that, if evolution is a radically contingent materialistic process driven by natural selection and random genetic variation, then there can be no place in it for divine providential causality. .... But it is important to note that, according to the Catholic understanding of divine causality, true contingency in the created order is not incompatible with a purposeful divine providence. Divine causality and created causality radically differ in kind and not only in degree. Thus, even the outcome of a truly contingent natural process can nonetheless fall within God’s providential plan for creation.

22. “There is grandeur in this view of life; with its several powers having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most wonderful and most beautiful have been, and are being evolved.” - C Darwin

23. Ken Miller • He told us we could use the previous slides • www.millerandlevine.com • Thanks!

24. In the immortal words, of “The Gru:” • “Be opinionated, just not ignorant.” A Final Quote

25. Dating • Geologic Record • Hypothetical library of all the known geological processes on Earth • Determined through inference and dating methods • Relative Dating (hee hee) • Sediments are constantly being laid down. • Over time, many layers form • If a fossil is in a layer below a different fossil, it is older than that fossil

26. Dating • Radiometric Dating • Radioactive isotopes decay and form new isotopes - the rate this happens is called the isotope’s half life • Ex: Potassium-40 decays to argon-40 and has a half life of 1.3 billion years • Half a sample will decay to argon-40 in 1.3 billion years • So if there are equal amounts of potassium-40 and argon-40 in an area, the sample has been in place 1.3 billion years • Carbon 14 has a half life of only 70,000 years for more recent sample dating

27. How does the geologic record help us? • What use is relative dating? • What is radiometric dating? • Why are different isotopes used in radiometric dating? Review

28. Charles Darwin • English naturalist (scientist) 1809-1882 • 1831, Darwin took a job as a naturalist on the HMS Beagle • Went on a 5-year scientific journey around the world • He collected many biological and fossil speciments • Combined with his previous and subsequent observations • Published On the Origin of Species by Natural Selection in 1859 • These ideas are a basic unifying theme of biology today • Without evolution, biology doesn’t make as much sense

29. Selection • Artificial selection • Breeding organisms with specific traits in order to produce offspring with identical traits • Natural selection • A mechanism for change in populations • Occurs when organisms with favorable traits survive, reproduce and pass their traits on to the next generation • Organisms with these traits are said to be more “fit” • Organisms without these traits are less likely to survive and reproduce Darwin awards

30. Adaptations • Adaptation • Verb - Evolution of a structure, behavior, or internal process that enables an organism to respond to environmental factors and live to produce offspring • Noun - Can also be the structure itself • Structural adaptations take a long time • Physiological adaptations can happen faster • Bacteria strains develop resistances to antibiotics fairly quickly

31. Evidence for Evolution • Fossil Record • A hypothetical “library” of all the fossils collected around the world • Fossils show changes throughout time • 99 percent of all animals are now extinct • Fossil record shows ancestors with similar characteristics

32. Evidence For Evolution • Anatomy • Homologous Structures are structural features with a common evolutionary origin • Ex: whale forelimb, crocodile forelimb, bird wing, human forelimb all look the same (p. 401) • Can you think of other examples? • Analogous Structures are body parts or organisms that do not have a common evolutionary origin but are similar in function • Bird, bat and butterfly wings • Show how organisms adapt to different ways of life and different conditions

33. Evidence for Evolution • Vestigial Structures are body structures that no longer serve their original purpose, but was probably useful to an ancestor • Ex: human appendix, pelvic bone in baleen whale, “tail” in humans, some human’s ability to wiggle their ears

34. Evidence for Evolution • Embryology – study of embryos of different species • Many species share features in the young embryos • Ex: Mammals, reptiles, birds and fish all have a tail and pharyngeal pouches (develop into different respiratory systems)

35. Evidence for Evolution • Biochemistry • Nearly all organisms share DNA, ATP, and many enzymes among their biochemical molecules • Organisms that share more similar enzymes, DNA sequences, etc. are more closely related

36. Human vs. Chimp Chromosomes

37. Other Hominids

38. Other Forms of Evidence • All primates need to “ingest” vitamin C because we can’t make it like we do Vitamin D • But, we do have 7 the genes to produce vitamin C • The 7th one is turned off in all primates • A mutated one was probably passed on because it provided no disadvantage due to fruit diets

39. How did Darwin come up with his ides for natural selection? • Some snakes have vestigial legs. Why is this considered evidence for evolution? • Explain how adaptations such as camouflage help species survive. • How do homologous structures provide evidence for evolution? • Why did birds and bats both get wings? • A parasite that lives in red blood cells causes the disease called malaria. In recent years, new strains of the parasite have appeared that are resistant to the drugs used to treat the disease. Explain how this could be an example of natural selection occurring. Review

40. Population Genetics • Populations evolve, not individuals • Natural selection acts on a range of phenotypes in a population • Genetic variation video • Evolution is often defined as a change in the frequency of an allele in a population over time

41. Population Genetics • All of the population’s genes are in a theoretical “gene pool” • The percentage a specific allele in the gene pool is called the allelic frequency • A population in which the frequency of alleles remains relatively the same over generations is in genetic equilibrium • Any change in this genetic equilibrium results in evolution

42. How to Stop Evolution – must meet all five requirements • Population is so large, chance alone cannot change relative frequency (genetic drift doesn’t occur) • Mutations do not occur • All genotypes have equal fitness (no natural selection) • No organisms leave or enter a population • Mating occurs at random Hardy-Weinberg Principle

43. Mutations • Mutation provides the raw material for evolution to act upon • Poor mutations are selected against, good mutations are selected for • Change the frequency of alleles • Examples: • Sometimes mutations are a compromise: • L4 & L5 in your backbone – poor design, but needed to stand upright “A Mutation Story”

44. Genetic Drift • Genetic drift is the alteration of allelic frequencies by chance events • Genetic drift can greatly affect small populations • Ex: The Amish community carries an allele that results in short arms and legs and extra fingers and toes (1/14 vs. 1/1000)

45. Natural Selection • Still the most significant factor that causes changes in established gene pools • Stabilizing Selection • Natural selection that favors average individuals (on a normal curve) in a population • Reduces variation in a population • Ex: With spiders, larger ones are found easier and eaten and small spiders can’t find food as easily

46. Natural Selection • Directional Selection • Natural selection favors one of the extreme variations of a trait • Can lead to rapid evolution • Ex: The food supply in an area is limited to hard nuts. Birds with short, strong beaks will survive • Disruptive Selection • Natural selection favors individuals with either extreme of a trait’s variation • Can lead to evolution of 2 new species • Ex: A shelled, marine organism called a limpet has white, tan, and dark shells. The white and dark shells blend in on different colored rocks. Tan gets eaten.

47. Species • A species is a group of organisms that look alike and can interbreed to produce fertile offspring in nature • Speciation is the evolution of new species • Occurs when members of similar populations no longer interbreed to produce fertile offspring within their natural environment

48. Causes of Speciation • 95% coincide with some sort of chromosomal rearrangement • Physical barriers • Volcanic eruptions, sea-level changes, new islands forming • These prevent interbreeding • Called geographic isolation • Over time, may have to adapt to new types of environments

49. Causes of Speciation • Reproductive Isolation • Two types • One occurs because of geographical reasons (migrate away) • One occurs because of behavioral reasons • Some mate in fall, some in spring

50. Polyploidy • Individual with a multiple of a normal set of chromosomes • How does this happen? • New zygotes may not develop the same way as parents due to different number of chromosomes • May result in speciation