1. Theory of Evolution
Inherit the Wind

2. Theory of Evolution

3. What is a theory? Theory of Evolution
Is an explanation, supported by observations and/or
experiments, that can be used to explain related
occurrences. Theories can be disproven

4. Theory of Evolution Evolution- The change of species over time.
Theory: The earth’s present day species developed from earlier distinctly different species.
Changes occurred in structure, function and behavior.

5. Evidence of Evolution Fossil Evidence Comparative Anatomy
Comparative Embryology
Comparative Biochemistry

6. Fossil Evidence Fossils provide the STRONGEST argument for evolution.
Fossils- Are the rare traces or remains of an organism that have been preserved by a natural process.
Fossils are used to compare the remains of ancient organisms with those living today.

7. Fossils
A fossil is some remnant of an organism that proves its existence
Imprints of bacteria, leaves or footprints
Insects, pollen, or flower parts in amber
Tools
Bones of organisms in sedimentary rock

8. Examples of Fossils
Insect in Amber
MOLD

9. Examples of Fossils
IMPRINT
ICE MAN

10. Fossil Evidence Relative dating
Oldest fossils are in the deepest sedimentary rock layers
The oldest fossils are on the bottom, and the youngest are the top layers.
Younger layers hold newer, more complex fossils

11. The fossil record shows…
Life has evolved from simple to more complex
Newer Organisms:
More complex
Older Organisms: More simplistic

12. Geological Record
Fossils indicate that simple organisms have evolved into increasingly complex multicellular organisms.
Scientists use phylogenetic trees to depict evolution, common ancestry and extinction.

13. Evolutionary - Phylogenic Tree
Species living at present time (top)
Ancestral common species (bottom)

14. What organisms are our closest relatives? Why?

15. Evolution of the Horse

17. Comparative studies
Researchers use comparative studies to establish evolutionary relationships between organisms

18. Comparative Anatomy Three Types 1) Homologous Structures
2) Analogous Structures
3) Vestigial Structures

19. Homologous Structures
Are physical traits that are similar in structure BUT differ in function.
Presence of Homologous Structures indicates that these animals evolved from a common ancestor.

20. Homologous Structures
The limbs of humans, cats, whales & bats are similar in skeletal structure, but vary in function.
This suggests these animals evolved from a common ancestor.

21. Analogous Structures
Body Parts that appear similar BUT have different internal structures based on an adaptation for the same function.
Organisms that share Analogous Structures DO NOT have a common ancestor.

22. Analogous Structures
Wings have evolved independently in insects, bats, birds and flying reptiles.

23. Vestigial Structures
Structures or organs that seem to have NO USEFUL Function.
Organisms having vestigial structures share a common ancestor with organisms in which the homologous structure is functional.

24. Vestigial Structures
Humans have a tailbone at the end of the spine and a non-functioning appendix.
Snakes and whales have remnants of both pelvic and limb bones.
---ancestors had legs and lived on land.

25. Comparative Embryology
Similarities in early development of different organisms can provide evidence of a common ancestor.
Ex. Fish, rabbit, pigs,
chickens and humans.

26. Comparative Biochemistry
The more closely related
organisms are, the more
similar is their biochemical
makeup.
Such as DNA, Amino Acid Sequence
Ex. Chlorophyll is the same basic molecule in all photosynthetic organisms.
The genetic code is universal.
Codons code for the same amino acid.
Similarities in DNA  Amino Acids  Protein

27. Chimpanzees and Humans
Humans and chimps share approximately 98.5% of their DNA.
Chimps are considered the closest living relative to humans.
Small amounts of DNA is responsible for individual differences from humans.

28. Comparative cytology Observing similarities in cell structures
All cells have some common organelles that perform identical functions
Plasma membrane, cytoplasm, and ribosomes

29. The “evolution” of Evolutionary Theories
Study of Fossils Lamarck Darwin essay The Origin of Species

31. Stated that structures appear because they are
Lamarck’s Theory:
Stated that structures appear because they are
needed…called the theory of Use & Disuse
****Acquired Traits****
ex. Longer necks in giraffes to reach food
Structures used become more developed
and structures not used will disappear

32. Lamarck’s Theory:
These traits that are developed get
passed down to next generation

33. Weissmann the “Miceman”
Weismann: (1870)
DISPROVED that acquired traits can be passed on to the next generation.
He cut off tails of mice then had them mate.
Their offspring had TAILS!!!!!!!!

34. “The Father of Evolution”
Charles Darwin
“The Father of Evolution”

35. Charles Darwin Theory of Natural Selection
Darwin served as a geologist, botanist, zoologist, and general man of science aboard the H.M.S. Beagle from

36. Darwin’s finches
These finches are one of the foundations of Darwin’s observations that led to his theory of evolution
Each finch has different adaptations to survive in their particular environment

37. Darwin observed 13 species of finches on the Galápagos Islands that were similar except for differences in body size, beak shape, and eating habits.

38. Darwin reasoned that the Galápagos finches must have had to compete for food…. After many generations, these groups of finches became separate species.

39. Charles Darwin
His theory had 6 main points

40. Darwin’s Six Points 1) Natural Selection 2) Overproduction
3) Competition
4) Variation
5) Adaptation
6) Speciation

41. NATURAL SELECTION
Organisms with FAVORABLE VARIATIONS would be better able to SURVIVE and REPRODUCE than organisms with unfavorable variations.
“Nature Selects” the survivors
The result of natural selection is evolution

42. NATURAL SELECTION

43. Overproduction
More offspring are produced than can survive (most die young).
Organisms such as bacteria, fish, insects, and rabbits have high reproductive rates because the chance that their young will survive is minimal.

44. Overproduction leads to
COMPETITION!!

45. COMPETITION
Organisms compete (fight) for life’s necessities which are limited resources.
Ex. Food, Shelter and Space, Mates, Water
Competition leads to survival of the fittest.
The Fittest reproduce & pass on their genes.

46. VARIATION Differences between individuals within a certain species.
This variation can lead to long term change

47. Why are variations important to a population?
Variation in a species increases the chances that some members will survive an environmental change.
Why is this important?

48. ADAPTATION Any inherited trait (structure or behavior)
that improves an organism’s chance of survival & reproduction in a given environment.

49. ADAPTATION
Camouflage
Blends in with environment
To Avoid Predators

50. ADAPTATION Mimicry Looking like other animals or organism
( Monarch and Viceroy )
To Avoid Predators

51. SPECIATION Formation of a new species.
Over many generations, favorable adaptations accumulate & unfavorable ones disappear.

52. Adaptive Radiation
Evolution of many species from one common ancestor due to natural selection

53. Adaptive Radiation
organisms spread into new environments and become adapted through natural selection. Became different enough that interbreeding became impossible

55. Geographic isolation A population is divided by a natural barrier
mountains
Deserts
Body of water
Landslide cause by an earthquake
Geographic isolation can instigate a speciation event—but genetic changes are necessary to complete the process

56. TYPES OF SPECIATION DIVERGENT EVOLUTION:
Occurs when organisms share a common ancestor but become geographically isolated and evolve separately.

57. TYPES OF SPECIATION Serval Cat CONVERGENT EVOLUTION:
Occurs when different species of different ancestors develop similar characteristics due to living in the same environment.
Manned Wolf

58. TYPES OF SPECIATION CO-EVOLUTION:
When an evolutionary change in one organism causes another organism to evolve because of their interdependence.
Bumblebees and the flowers they pollinate have coevolved so that both have become dependent on each other for survival.

59. Extinction
Disappearance of an entire species.   
It can be caused by temperature changes, pollution, or landscape changes.
When the adaptive characteristics of a species do not allow it to survive in the environment, it becomes extinct.

60. WHICH of DARWIN’S 6 POINTS is illustrated in the following pictures?

69. Genetic Basis for Variations
Sexual reproduction recombination of genes
Meiosis
Crossing over
Mutations

70. Genetic Basis of Evolution
NEW INHERITABLE CHARACTERISTICS:
Traits that can be passed from a parent to its offspring.
Result in new combinations of existing genes.

71. Genetic Basis of Evolution
MUTATIONS:
A mutation is a change in an organism’s DNA.
Random mutations in sperm and egg cells lead to new characteristics in offspring.
*Mutations in body cells can only be passed on to other body cells.

72. Genetic Basis of Evolution
MUTATIONS:
Mutations lead to variation, which increases the chance that some members of a species will survive changes in the environment.

73. RATE OF EVOLUTION GRADUALISM:
Evolution occurs slowly and continuously over thousands & millions of years.

74. RATE OF EVOLUTION Punctuated Equilibrium Sudden change in environment
A species remains the same for extended periods of time (millions) of years.
And suddenly over
thousands of years a new
species appears.
Sudden change in environment

75. Gradualism vs Punctuated Equilibrium

77. Human Influences on Modern Evolution
1) Insecticide Resistance
2) Antibiotic Resistance
3) Artificial Selection
4) Industrial Melanism

78. INSECTICIDE RESISTANCE

79. INSECTICIDE RESISTANCE
HUMAN INFLUENCE:
Humans create and use insecticides to kill insect pests. Ex. DDT
EFFECTS OF HUMAN INFLUENCE:
Insects that have the insecticide resistance gene are best adapted because it enables them to survive, reproduce and pass on the resistance gene.
Insecticides used today will not work in the future, due to a large # of resistant insects.

80. ANTIBIOTIC RESISTANCE

81. ANTIBIOTIC RESISTANCE
HUMAN INFLUENCE:
Humans make and use antibiotics to
kill bacteria. Ex. Penicillin
EFFECTS OF HUMAN INFLUENCE:
Non-resistant bacteria die off because they lack the resistance gene, but resistant bacteria survive, reproduce and pass on their gene.
Antibiotics that are used today will not work in the future  discover new antibiotics.

82. Antibiotic Resistance
The bacteria WITHOUT the resistance will be killed, while those that are RESISTANT will survive and pass on their genes for antibiotic resistance.
The antibiotic is the selecting agent
Resistant Bacteria
Antibiotic X

83. ARTIFICIAL SELECTION HUMAN INFLUENCES:
Humans select for the desirable traits in plants and animals, and breed these organisms.
EFFECTS OF HUMAN INFLUENCE:
Increase in Variation- produce new varieties of plants and animals.
Decrease in Variation- when organisms with the same traits are bred over and over to produce offspring with the same traits.

85. INDUSTRIAL MELANISM

86. For example: The peppered moth

87. INDUSTRIAL MELANISM (Peppered Moths of England)
HUMAN INFLUENCE:
In the 1800’s the industrial revolution in England resulted in an increase in pollution, tar and soot in the environment.
EFFECTS OF HUMAN INFLUENCE:
Nature started to select for the black moths to survive, reproduce and pass on their genes because they were best adapted to the polluted trees. White moths were easily captured by birds and started to die off.