FRIDAY LAB: Mudworms

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2 FRIDAY LAB: Mudworms sexual reproduction rare asexual reproduction (fragmentation) common Friday Lab: Explore Mudworm Fragmentation & Reconstruction

3 The Evolution of Animals

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21 How did animal diversity happen?? Conservative Christianity claims a 6 day creation process. Less conservative Christians do not accept that. (e.g., Catholics, Presbyterians, Methodists, Episcopalians, etc. )

22 Reasons to not believe in Bible literally?? Fossil record + Sedimentary rock strata (layers) The Law of Superposition

23 Law of Superposition Rock Strata

24 Law of Superposition Analogous to seeing the history of an old house by stripping layers of wall paper.

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27 Fossils from the Burgess Shale

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29 Fossil record + Sedimentary strata (Law of Superposition) Now. Fossil record + Accurate rock dating using radioisotope techniques ( 14 C, 40 K, etc.)

30 Rock Strata NOW these strata can be accurately dated!!

31 1 DAY = 4.5 BILLION YEARS

32 The Role of Charles Darwin Career attempt 1: Med School Career attempt 2: The Ministry Career attempt 3: Naturalist (scientist)

33 Age 22: Set sail on the Beagle returned 5 years later with radical ideas.

34 So Darwin discovered evolution ABSOLUTELY NOT!!! No one person made that discovery Earlier generations of biologists slowly came to evolutionary viewpoints

35 Darwin s Contribution: EVOLUTION by NATURAL SELECTION

36 The book that rocked the world in 1859 in 2011, acceptance is stronger than ever.

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38 Darwin began his book by discussing Artificial selection Example??

39 Basic Elements of Evolution by Natural Selection

40 All Animals Have Excessive Reproductive Capacity 750 years 2 elephants 19,000,000 elephants 5 months 2 houseflies 191 x houseflies 48 hours 1 bacterium bacteria cover the earth to a depth of 7 feet 2 humans??

41 Anatomical Variability

42 Physiological Variability

43 Biochemical Variability Behavioral Variability Immunological Variability etc. etc.

44 Survival Advantage??

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47 Evolution by Natural Selection Know This!!

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49 Melanic (= black) version

50 Natural Selection acts via many forces: Food & water quantity/quality Climate Parasites Disease Competitors Predators

51 DARWIN Awards The importance of removing weak genes from the gene pool Two local men were injured when their pickup truck left the road and struck a tree near Cotton Patch on State Highway 38 early Monday. Woodruff County deputy Dovey Snyder reported the accident shortly after midnight Monday. Thurston Poole, 33, of Des Arc, and Billy Ray Wallis, 38, of Little Rock, were returning to Des Arc after a frog catching trip. On an overcast Sunday night, Pooles pickup truck headlights malfunctioned. The two men concluded that the headlight fuse on the older-model truck had burned out. As a replacement fuse was not available, Wallis noticed that the 22 caliber bullets from his pistol fit perfectly into the fuse box next to the steering-wheel column. Upon inserting the bullet the headlights again began to operate properly, and the two men proceeded on eastbound toward the White River Bridge. After traveling approximately 20 miles, and just before crossing the river, the bullet apparently overheated, discharged, and struck Poole in the testicles. The vehicle swerved sharply right, exiting the pavement, and striking a tree Poole suffered only minor cuts and abrasions from the accident but will require extensive surgery to repair the damage to his testicles, which will never operate as intended. Wallis sustained a broken clavicle and was treated and released. "Thank God we weren't on that bridge when Thurston shot his b***s off, or we might both be dead," stated Wallis. (Though Poole and Wallis did not die as a result of their misadventure as normally required by Darwin Award Official Rules, it can be argued that Poole did, in fact, effectively remove himself from the gene pool.)

52 Natural selection pushes species TO BE ADAPTED to their environment. Adaptation may require traits to become optimized. Why optimized? Why not minimized or maximized?? EXAMPLE: Seal blubber: how thick?

53 Swimming in cold water

54 Natural selection pushes species TO BE ADAPTED to their environment. Adaptation may require traits to become optimized. Blubber: What is optimal for a seal? optimal

55 Is the giraffe neck optimal? Wouldn t an even longer neck be better?? Brain needs blood How high can blood be pumped? How much blood pressure can a heart generate?

56 2 Examples of evolution that are. human-induced unwanted

57 Key: genetic variability Rapid and unwanted evolution!!

58 Is rapid unwanted evolution a problem in hospitals??

59 PROFOUND QUESTION Are humans (Homo sapiens) still evolving? If yes in what ways?? If no why not??

60 Important outcome of natural selection: New Species The process of forming a new species is called SPECIATION. How does speciation work??

61 Lots of time many generations

62 Branching Speciation: 1 species evolving into 2 species. Starting point: single interbreeding population... that gets split! Why is a split necessary?? A population split RETARDS GENE FLOW reproductive isolation

63 Splits involve habitat fragmentation EXAMPLE: earthquake creating a waterfall on a river EXAMPLE: rise in sea level EXAMPLE: new road construction

64 Road-building will fragment salamander habitat

65 Unbroken river with a population of fish

66 Geological event produces a waterfall creates reproductive isolation Gene Flow???

67 High Tide Shore-line Global warming as an isolating mechanism?? O C E A N

68 Global warming as an isolating mechanism New Low Tide O C E A N Gene Flow???

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71 Gene Flow??

72 Evolution of antibiotic resistance: What is the natural selection??

73 Staphylococcus aureus is one of the major resistant pathogens. Found on the mucous membranes and the skin of around a third of the population, it is extremely adaptable to antibiotic pressure. It was the first bacterium in which penicillin resistance was found in 1947, just four years after the drug started being mass-produced. MRSA (methicillin-resistant Staphylococcus aureus) was first detected in Britain in 1961 MRSA was responsible for 37% of fatal cases of blood poisoning in the UK in 1999, up from 4% in Half of all S. aureus infections in the US are resistant to penicillin, methicillin, tetracycline and erythromycin.