1. History of Life and the Origin of Species
Mrs. Stewart
Honors biology
Central Magnet School

2. Standards:
CCSS ELA
I can trace the historical development of the theory of evolution
I can summarize the evidence for the theory of evolution
CCSS ELA
I can critique and evaluate competing evolutionary arguments based on scientific knowledge, empirical evidence and logical arguments regarding relevant factors.

3. Objectives (today, I will…)
Differentiate between spontaneous generation and biogenesis
Differentiate between Charles Darwin and Jean-Baptiste Lamarck

4. Choose… But choose wisely.
Decide which partner is the bird and which is the cat.

5. History of Life Biogenesis: Spontaneous Generation:
All living things come from other living things
Spontaneous Generation:
Living things could arise from nonliving things

6. Redi’s experiment Previous idea: Flies were created from rotten meat
Redi: Meat kept away from adult flies would not produce maggots

7. Spallanzani & Pasteur
Spallanzani – tried to disprove that microorganisms arose from a “vital force” in the air
Pasteur – improved spallanzani’s experiment to eliminate the flaw of “no air”

8. Cats
Tell your bird how Pasteur improved upon Spallanzani’s experiment to disprove spontaneous generation

9. Endosymbiosis Where/how did mitochondria get their own DNA?
How did chloroplasts become so specialized?
Theory of Endosymbiosis:
Aerobic prokaryotes were engulfed by eukaryotic cells evolved into mitochondria (which perform aerobic respiration)
Photosynthetic prokaryotes were engulfed by plant cells and evolved into chloroplasts (where photosynthesis occurs)

10. Ch. 15.1 – 15.2 History of Evolution
Mrs. Stewart
Honors Biology
Central Magnet School

11. What is Evolution? Dictionary:
The gradual development/change of something; especially from a simple to complex form.
Text book:
(In biology) Generally, the process of change by which new species develop from pre-existing species over time
Evolution of Dance

12. Birds
Tell your cat what Evolution means. Give an example (not one that Mrs. Stewart used)

13. 18th Century Ideas 19th Century Ideas About living species:
About the Earth:
Uniformitarianism
All species were permanent and unchanging.
Earth was only a few thousand years old and unchanging.
19th Century Ideas
Idea by Charles Lyell that said geologic processes happed slowly over time and that some features of the Earth may take millions of years to form.

14. Cats
Give your bird an example to support Lyell’s theory.

15. Jean-Baptiste Lamarck
French Naturalist
1809
Lamarck’s Hypothesis: by selective use or disuse of organs, organisms acquire or lose certain traits. These traits could then be passed on to their offspring.
Lamarck believed over time, this process led to change in a species.

16. Lamarck’s Hypothesis
1. Tendency toward perfection - All organisms have an innate tendency toward complexity and perfection, so they are continually changing to be more successful in their environment 2. Use and disuse - Organisms can alter their bodies/organs by use or disuse 3. Inheritance of acquired traits - Organisms can pass on those altered body parts/organs to the offspring

18. Birds
What did Lamarck get right?

19. Cats
What did Lamarck get wrong?

20. Lamarck the Loser First to develop a hypothesis of evolution
First to realize organisms adapt to their environment
But, Behavior has no effect on inheritable characteristics

21. Ch. 15.1 – 15.2 History of Evolution
Mrs. Stewart
Honors Biology
Central Magnet School

22. Charles Darwin
1809 – 1882
Naturalist – study of nature and the natural world
Sailed on the HMS Beagle in 1831
Every time the ship docked, Darwin went ashore to collect plant and animal specimens

23. Darwin’s observations piqued his interest in the diversity of life he observed.
Darwin even found evidence that suggested species once present on earth had vanished.
Researchers today speculate that 99.9% of all species that ever inhabited earth are now extinct.

24. Galapagos Islands
The islands were close together, but had very different climates
Smallest and lowest islands = hot, dry & barren
Hood Island = sparse vegetation
Higher islands had greater rainfall and a different assortment of plants/animals
Isabella Island = rich vegetation
Land Tortoise shell shapes could be used to identify which island it inhabited

25. What observations can YOU make about these species of land tortoise?
Hood Island Tortoise
Pinta Island Tortoise
What predictions can YOU make about the island environment for each tortoise?
What observations can YOU make about these species of land tortoise?
Isabella Island Tortoise

26. Which island would you predict has only low-lying vegetation?
Hood Island Tortoise
Pinta Island Tortoise
Which island would you predict has only low-lying vegetation?
Isabella Island Tortoise

27. Darwin’s Idea
Darwin observed that the plants and animals varied noticeably among the different Galapagos Islands.
However, Darwin wondered if animals living on different islands had once been members of the same species – originating from the same South American ancestor

28. Darwin’s Finches
Darwin observed many different types of “finch” and noticed several different beak shapes.
Why?
He began to notice different shaped beaks were “adaptations” for different food sources

29. Religion’s Role Darwin was a devout Catholic
He knew that his ideas, based on what he observed would provoke the catholic church
He debated over what to do for 25 years.

30. Darwin’s Theory – Descent With Modification
The Origin of Species by Means of Natural Selection – 1858
Every species – living or extinct – descended by reproduction from preexisting species
AND
Species must be able to change over time

31. Mrs. Stewart Honors biology Central Magnet School
Natural Selection
Mrs. Stewart
Honors biology
Central Magnet School

32. Review What was Lamarck’s hypothesis? What did Darwin believe?
Inheritance of acquired traits
Species changed as environment changed – adaptation and survival of the fittest

33. Standards:
CCSS ELA
I can trace the historical development of the theory of evolution
I can summarize the evidence for the theory of evolution
CCSS ELA
I can critique and evaluate competing evolutionary arguments based on scientific knowledge, empirical evidence and logical arguments regarding relevant factors.

34. Objective (Today I will…)
Explain the idea of “natural selection” and determine “fittest”
Examine how adaptations help animals survive better

35. Darwin’s reasoning for Natural Selection
Overproduction – more offspring are produced than can survive due to competition for resources
Genetic Variation – within a population, individuals have different traits. New traits may appear spontaneously.
Struggle to survive – constant competition may cause some variations/traits to be advantageous
Differential Reproduction – Organisms with the best adaptations will survive and reproduce, thus the advantageous adaptations will become most prevalent in the population.

36. Evolution by Natural Selection
Struggle for existence – each member of a species competes regularly for food, living space and other necessities of life.
main needs: Food, water, living space and ability to reproduce
Who wins?

37. Think – Pair – Share
How can we describe Natural Selection in just 4 words?

38. Survival of the Fittest
How well suited an organism is to it’s environment
Does fittest mean strongest?
Does fittest mean in the best shape?
Fitness – the ability of an individual to survive and reproduce
The result of adaptations

39. What determines fitness?
The Environment!

40. Fitness leads to evolution

41. Fitness leads to evolution
Peppered Moth evolution

42. Peppered moth virtual lab

43. Survival of the Fittest
Fittest – the individuals most capable to survive and reproduce for multiple generations
The traits selected as the most useful for survival and reproduction are determined by the organisms environment
Natural Selection accounts for Descent with Modification as species become better adapted to different environments.

44. Birds
Explain to your cat how the environment can determine fitness – use a specific plant or animal as an example.
(Not one Mrs. Stewart gave you)

45. What is a Population?
A group of organisms of the same species, that live in the same area, AND that interbreed

46. Adaptation vs. Acclimatization
Adaptation - Changes in traits in populations over time
Example: White moth population becoming a black moth population after 5 generations.
Acclimatization – individual organism changes physiologically
Example: growing thicker fur in winter

47. Adaptations
Any inherited characteristic that increases an organism’s (and therefore, a populations) ability to survive and reproduce
Anatomical or structural characteristics
Porcupine quills - protection
Longer necks in giraffes – find food
Physiological processes
How a plant performs photosynthesis
Instinctual Behaviors
Hunting in packs
Living in burrows

49. Can You… Differentiate between biogenesis and spontaneous generation
Differentiate between Charles Darwin and Jean-Baptiste Lamarck
Explain the idea of “natural selection” and determine “fittest”

50. Mrs. Stewart Honors Biology Central Magnet School
Evidence of Evolution
Mrs. Stewart
Honors Biology
Central Magnet School

51. Standards:
CLE – Explain how genetic variation in a population and changing environmental conditions are associated with adaptation and the emergence of new species.

52. Descent with Modification
Over long periods of time, natural selection produces organisms with different structures, niches or occupy different habitats than their ancestors.
Each living species has descended, with changes, from other species over time.
Result: species today look/act different from their ancestors

53. Common Descent
Look back: Tigers, panthers and cheetahs all share a common ancestor
Look back further: you will find ancestors that these cats share with horses, dogs and bats.
Farther back: common ancestors of mammals, birds, alligators and fishes.
Logic: looking far enough back we should find the common ancestor for all living things

54. Common Descent

55. Evidence of Evolution Homologous & Analogous Structures Fossil Records
Vestigial Structures
Evidence of Evolution
Comparative Embryology
Molecular Biology

56. Fossil Records Fossils - preserved remains of ancient organisms
Compare fossils from older layers and younger layers and show changes in species over time

57. Fossil Records
Compare fossils found around the world and we can infer when and where different organisms existed.
Fossils also provide evidence about the environment in which the organism existed and for which the organism adapted

58. Transitional Species
Fossil records show species which have features that are intermediate between those of hypothesized ancestors and later descendant species

59. Homologous vs. Analogous Structures
Homologous – refers to structures that share the same basic structure but may differ greatly in function
Analogous – refers to structures that vary greatly in structure but may share the same function

60. Homologous Body Structures

61. Homologous Body Structures
The limbs of reptiles, birds and mammals (arms, wings, legs and flippers) vary greatly in function but are all constructed from the same basic bones.

62. Analogous Structures

63. Vestigial Structures
organs/body parts that were once used, but by natural or artificial selection, are no longer necessary

64. Vestigial Organs
Appendix

65. Vestigial Organs
Hip bone in a whale

66. Vestigial Organs
Tailbone in humans

67. Vestigial Organs
Plica Luminaris = Third Eyelid

68. Similarities in Embryology
The early stages, or embryos, of many animals with backbones are very similar.
Does this mean that a human embryo is ever identical to a fish, or a bird embryo? NO
But, many embryos look especially similar during early stages of development.

69. Fish Salamander Tortoise Chicken Pig Man

70. Comparative Embryology
What do these similarities mean?
The same groups of embryonic cells develop in the same order and in similar patterns to produce the tissues and organs of all vertebrates.

71. All animals go through this process
Its at the blastocoel step that we differ
Blastopore could become mouth or anus, etc.

72. The number of amino acids that differ from human hemoglobin
Molecular Biology
Using new technology, we can see how many DNA and RNA sequences organisms share in common
Amino acid sequences used to determine how closely related different species are.
The number of amino acids that differ from human hemoglobin

73. Molecular Biology Amino Acid Similarities
Which two plants are the most closely related according to this chart?

74. Assignment:
Evidence of evolution dry lab activity packet

75. Exit Ticket: Socrative.com
Room Number: Stewart 348
Question: How does the environment determine the “fittest” individual?