1 Evolution Diversity of Life copyright cmassengale

2 Early Ideas On Earth’s Organisms Aristotle believed species were fixed creations arranged by their complexity Aristotle believed species were fixed creations arranged by their complexity Idea lasted 2000 years Idea lasted 2000 years copyright cmassengale

3 Early Ideas On Earth’s Organisms Linnaeus – 1 st to group similar organisms and assign them Latin names Linnaeus – 1 st to group similar organisms and assign them Latin names Two word name (Genus species) Two word name (Genus species) Known as Binomial nomenclature Known as Binomial nomenclature copyright cmassengale

Spontaneous Generation Until the mid 1800s, people believed that simple living organisms could come into being by spontaneous generation. Until the mid 1800s, people believed that simple living organisms could come into being by spontaneous generation. This was the idea that nonliving things can give rise to living organisms. This was the idea that nonliving things can give rise to living organisms. copyright cmassengale4

Spontaneous Generation Francesco Redi publicly opposed the idea of spontaneous generation. He maintained that nothing living could arise from something nonliving. Francesco Redi publicly opposed the idea of spontaneous generation. He maintained that nothing living could arise from something nonliving. Louis Pasteur also disproved S. G. in the 1850s by studying microorganisms in meat broth. Louis Pasteur also disproved S. G. in the 1850s by studying microorganisms in meat broth. copyright cmassengale5

Other Types of Evolution Chemical evolution-the process by which increasingly complex elements, molecules, and compounds arose from simpler inorganic molecules and elements Chemical evolution-the process by which increasingly complex elements, molecules, and compounds arose from simpler inorganic molecules and elements copyright cmassengale6

7 Definition of Evolution Evolution is the slow, gradual change in a population of organisms over time copyright cmassengale

8 Evolutionary Time Scales Long time scale events that create and destroy species. Macroevolution: Long time scale events that create and destroy species. copyright cmassengale

9 Microevolution: Short time scale events (generation- to-generation) that change the genotypes and phenotypes of populations Evolutionary Time Scales copyright cmassengale

Terms Continued Species: a group of individuals that actually or potentially interbreed in nature Species: a group of individuals that actually or potentially interbreed in nature Speciation: a lineage-splitting event that produces two or more separate species Speciation: a lineage-splitting event that produces two or more separate species Adaptation: a feature that is common in a population because it provides some improved function Adaptation: a feature that is common in a population because it provides some improved function copyright cmassengale10

Radiometric and relative dating: two methods used to determine the age of a fossil Radiometric and relative dating: two methods used to determine the age of a fossil Vestigial structures: organs or appendages that may not be necessary in an organism today, but had a function many years ago Vestigial structures: organs or appendages that may not be necessary in an organism today, but had a function many years ago copyright cmassengale11

Analagous structures-structures that have the same functions, but different structures. (ex: butterfly wing and bird wing) Analagous structures-structures that have the same functions, but different structures. (ex: butterfly wing and bird wing) Homologous structures: develop from the same tissues as embryos and have similar internal structures, but they may serve a different function Homologous structures: develop from the same tissues as embryos and have similar internal structures, but they may serve a different function copyright cmassengale12

13 : Contributor’s to Darwin’s thinking included: Charles Lyell –uniformintarianism (geologic processes still changing Earth)Charles Lyell –uniformintarianism (geologic processes still changing Earth) Georges Cuvier – species extinction (Catastrophism)Georges Cuvier – species extinction (Catastrophism) Thomas Malthus – struggle for existence (resources)Thomas Malthus – struggle for existence (resources) copyright cmassengale

14 : Contributor’s to Darwin’s thinking included: James Hutton - GradualismJames Hutton - Gradualism John Baptiste Lamarck – Inheritance of acquired Characteristics and Law of Use and DisuseJohn Baptiste Lamarck – Inheritance of acquired Characteristics and Law of Use and Disuse Alfred Russel Wallace – organisms evolved from common ancestorsAlfred Russel Wallace – organisms evolved from common ancestors copyright cmassengale

15 Evolutionary Timeline copyright cmassengale

16 Catastrophism Idea proposed by George Cuvier Idea proposed by George Cuvier Studied fossil in sedimentary rock strata of Paris Studied fossil in sedimentary rock strata of Paris Found some species completely disappeared in more recent layers Found some species completely disappeared in more recent layers copyright cmassengale

17 Catastrophism Stated that species disappear due to a catastrophic event of the earth’s crust (volcano, earthquake…) Stated that species disappear due to a catastrophic event of the earth’s crust (volcano, earthquake…) copyright cmassengale

18 Hutton’s Theory of Geological Change Changes in Earth’s crust due to slow continuous processes Changes in Earth’s crust due to slow continuous processes Idea Known as Gradualism Idea Known as Gradualism copyright cmassengale

19 Charles Lyell Proposed theory of Uniformintarianism Proposed theory of Uniformintarianism Geological processes at uniform rates building & wearing down Earth’s crust Geological processes at uniform rates building & wearing down Earth’s crust Proposed that the Earth was millions of years instead of a few thousand years old Proposed that the Earth was millions of years instead of a few thousand years old copyright cmassengale

20 Lamarck’s Theory of Evolution Jean-Baptiste Lamarck, 1809 Jean-Baptiste Lamarck, 1809 One Of First Scientists To Understand That Change Occurs Over Time One Of First Scientists To Understand That Change Occurs Over Time Stated that Changes Are Adaptations To Environment acquired in an organism’s lifetime Stated that Changes Are Adaptations To Environment acquired in an organism’s lifetime Said acquired changes were passed to offspring Said acquired changes were passed to offspring copyright cmassengale

21 Lamarck’s Theory of Evolution Idea called Law of Use and Disuse Idea called Law of Use and Disuse If a body part were used, it got stronger If a body part were used, it got stronger If body part NOT used, it deteriorated If body part NOT used, it deteriorated copyright cmassengale

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23 Lamarck’s Mistakes Lamarck Did NOT Know how traits were inherited (Traits are passed through genes) Lamarck Did NOT Know how traits were inherited (Traits are passed through genes) Genes Are NOT Changed By Activities In Life Genes Are NOT Changed By Activities In Life Change Through Mutation Occurs Before An Organism Is Born Change Through Mutation Occurs Before An Organism Is Born copyright cmassengale

24 Wallace’s Contribution Alfred Russel Wallace Independently came to same Conclusion as Darwin that species changed over time because of their struggle for existenceAlfred Russel Wallace Independently came to same Conclusion as Darwin that species changed over time because of their struggle for existence When Darwin read Wallace’s essay, he knew he had to publish his findingsWhen Darwin read Wallace’s essay, he knew he had to publish his findings copyright cmassengale

25 The Struggle for Existence Malthus’ Influence: –High Birth Rates & Limited Resources Would Force Life & Death Competition Each Species Struggles For: –Food –Living Space –Mates copyright cmassengale

26 Voyage of the Beagle Charles Darwin Born Feb. 12, 1809 Born Feb. 12, 1809 Joined Crew of HMS Beagle, 1831 Joined Crew of HMS Beagle, 1831 Naturalist Naturalist 5 Year Voyage around world 5 Year Voyage around world copyright cmassengale

27 HMS Beagle’s Voyage copyright cmassengale

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30 Darwin’s Observations Patterns of Diversity were shown Patterns of Diversity were shown Unique Adaptations in organisms Unique Adaptations in organisms Species Not Evenly Distributed Species Not Evenly Distributed »Australia, Kangaroos, but No Rabbits »S. America, Llamas copyright cmassengale

31 Darwin’s Observations Both Living Organisms & Fossils collected Both Living Organisms & Fossils collected Fossils included: Fossils included: »Trilobites »Giant Ground Sloth of South America This species NO longer existed. What had happened to them? copyright cmassengale

32 Evidence for Evolution – The Fossil Record copyright cmassengale

33 Darwin’s Conclusion Production of more individuals than can be supported by the environment leads to a struggle for existence among individuals Only a fraction of offspring survive each generation Survival of the Fittest copyright cmassengale

34 Darwin’s Conclusion Individuals who inherit characteristics most fit for their environment are likely to leave more offspring than less fit individuals Called Natural Selection copyright cmassengale

35 Darwin’s Theory of Evolution Organisms Change Over Time copyright cmassengale

36 Common Descent with Modification Darwin proposed that organisms descended from common ancestors Darwin proposed that organisms descended from common ancestors Idea that organisms change with time, diverging from a common form Idea that organisms change with time, diverging from a common form Caused evolution of new species Caused evolution of new species copyright cmassengale

37. Natural Selection Driving force for evolution Driving force for evolution During the struggle for resources, strongest survive & reproduce During the struggle for resources, strongest survive & reproduce Idea that at least some of the differences between individuals, which impact their survival and fertility, are inheritable Idea that at least some of the differences between individuals, which impact their survival and fertility, are inheritable copyright cmassengale

38 Natural Variation and Artificial Selection Natural Variation Natural Variation –Differences Among Individuals Of A Species Artificial Selection Artificial Selection –Selective Breeding To Enhance Desired Traits Among Stock or Crops copyright cmassengale

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40 Evolution By Natural Selection Concepts The Struggle for Existence (compete for food, mates, space, water, etc.) The Struggle for Existence (compete for food, mates, space, water, etc.) Survival of the Fittest (strongest able to survive and reproduce) Survival of the Fittest (strongest able to survive and reproduce) Descent with Modification (new species arise from common ancestor replacing less fit species) Descent with Modification (new species arise from common ancestor replacing less fit species) copyright cmassengale

41 Survival of the Fittest Adaptations Can Be: – –Physical »Speed, Camouflage, Claws, Quills, etc. –Behavioral »Solitary, Herds, Packs, Activity, etc. copyright cmassengale

42 Survival of the Fittest Is Central To The Process Of Evolution Fitness Is Central To The Process Of Evolution Individuals With Low Fitness Individuals With Low Fitness –Die –Produce Few Offspring Survival of the Fittest AKA AKA Natural Selection copyright cmassengale

43 Descent With Modification Implies Implies –All Living Organisms Are Related –Single Tree of Life »DNA, Body Structures, Energy Sources Common Descent –All Species, Living & Extinct, Were Derived From Common Ancestors copyright cmassengale

44 Descent With Modification copyright cmassengale

45 Theory of Evolution Today Supporting Evidence copyright cmassengale

46 Homologous Structures copyright cmassengale

47 Evidence for Evolution - Comparative Embryology Similarities In Embryonic Development copyright cmassengale

48 Similarities in DNA Sequence copyright cmassengale

49 Evolution of pesticide resistance in response to selection copyright cmassengale

50 Evidence for Evolution – Evolution Observed Evolution of drug-resistance in HIV copyright cmassengale

51 Evidence of Evolution Key Concept Darwin Argued That Living Things Have Been Evolving On Earth For Millions of Years. Evidence For This Process Could Be Found In: –The Fossil Record –The Geographical Distribution of Living Species –Homologous Structures of Living Organisms –Similarities In Early Development copyright cmassengale

52 Fossil Record Earth is Billions of Years Old Earth is Billions of Years Old Fossils In Different Layers of Rock (sedimentary Rock Strata) Showed Evidence Of Gradual Change Over Time Fossils In Different Layers of Rock (sedimentary Rock Strata) Showed Evidence Of Gradual Change Over Time copyright cmassengale

53 Geographic Distribution of Living Species Different Animals On Different Continents But Similar Adaptations To Shared Environments Different Animals On Different Continents But Similar Adaptations To Shared Environments copyright cmassengale

54 Homologous Body Structures Scientists Noticed Animals With Backbones (Vertebrates) Had Similar Bone Structure Scientists Noticed Animals With Backbones (Vertebrates) Had Similar Bone Structure May Differ In Form or Function May Differ In Form or Function Limb Bones Develop In Similar Patterns Limb Bones Develop In Similar Patterns »Arms, Wings, Legs, Flippers copyright cmassengale

55 Homologous Body Structures Structures That Have Different Mature Forms But Develop From The Same Embryonic Tissues Structures That Have Different Mature Forms But Develop From The Same Embryonic Tissues Strong Evidence That All Four- Limbed Animals With Backbones Descended, With Modification, From A Common Ancestor Strong Evidence That All Four- Limbed Animals With Backbones Descended, With Modification, From A Common Ancestor Help Scientist Group Animals Help Scientist Group Animals copyright cmassengale

56 Homologous Body Structures copyright cmassengale

57 Homologous Body Structures Not All Serve Important Functions Not All Serve Important Functions –Vestigial Organs »Appendix In Man »Legs On Skinks copyright cmassengale

58 Similarities In Early Development Embryonic Structures Of Different Species Show Significant Similarities Embryonic Structures Of Different Species Show Significant Similarities Embryo – early stages of vertebrate development Embryo – early stages of vertebrate development copyright cmassengale

59 ChickenTurtle Rat copyright cmassengale