Presentation is loading. Please wait.

Presentation is loading. Please wait.

Chapter 9 Evolution Barron’s Book.

Similar presentations

Presentation on theme: "Chapter 9 Evolution Barron’s Book."— Presentation transcript:

1 Chapter 9 Evolution Barron’s Book

2 Microevolution House sparrows have adapted to the climate of North America, ] mosquitoes have evolved in response to global warming, and insects have evolved resistance to our pesticides. These are all examples of microevolution — evolution on a small scale.



5 Macroevolution


7 Anagenesis vs. Cladogenesis

8 Evidence for Evolution
We will discuss FIVE

9 Fossil Record Transitional fossils

10 Comparative Anatomy Homologous

11 Analogous

12 Vestigial

13 Comparative Embryology

14 Comparative Embryology

15 Comparative Embryology


17 Molecular Biology Cytochrome C – polypeptide (amino acid sequence)


19 Biogeography

20 Biogeography

21 Most of the 140 species of marsupials in Australia are found nowhere else in the world.

22 Worldwide Distribution of the Order Marsupiala
Common Names Scientific Name No. Genera No. Species Distribution Oppossums Didelphidae 12 70 Americas Marsupial Mice, Marsupial Cats, Tasmanian Devil Dasyuridae 14 50 Australasia Tasmanian Wolf Thylacinidae 1 Tasmania Numbats/Banded Anteaters Myrmecobiidae Australia Bandicoots Peramelidae 8 18 Shrew Oppossums Caenolestidae 3 7 South America Possums, Cuscuses, Gledero, Ringtails Phalangeridae 13 40 Noolkanger or Honey Possum Tarsipedidae Koalas Phoscolaratidae Wombats Vombatidae 2 4 Kangaroo/Wallabies, Potoroos, Rat Kangaroos Macrophodidae 15 47



25 Bi-nomial nomenclature
Homo sapiens Lizardus Dominicanus


27 Cuvier

28 Hutton and Lyell

29 Lamarck “acquired characteristics”

30 Alfred Wallace Published an essay discussing natural selection, prompting Darwin to publish his book

31 Charles Darwin Early 1840’s theory is worked out
Publishes “On the origin of Species” in 1859

32 4 tenets of natural selection
Over population




36 Advantageous traits



39 Types of Selection Stabilizing




43 MRSA - The deadliest form of Staph
MRSA stands for methicillin-resistant staphylococcus aureus Staph bacteria that are resistant to the action of methicillin and related antibiotics are referred to as MRSA MRSA are not only resistant to all penicillin-like antibiotics, but they are often resistant to many other types of antibiotics as well. Infections with MRSA can be costly and difficult to treat because of limited antibiotic options. The proportion of staph infections that are methicillin-resistant has been steadily increasing, especially in the last years. By 2003, the percentage of MRSA among all staph isolates had risen three-fold to 38.6%. Almost 40% of staph found is MRSA now! MRSA is spread by physical contact, person to person, or person to contaminated object MRSA symptoms for the most part, not different from any other staph infection Diagnosis is confirmed by identifying the bacteria grown in a laboratory culture from a sample. The sample may be from a sterile site, such as blood or cerebrospinal fluid (CSF), or from a non-sterile site such as a draining lesion or a swab of the back of the nose.

44 Sexual Selection sexual dimorphism bestows upon the females a large, pink, pillowy buttocks sexual dimorphism bestows upon the females a large, pink, pillowy buttocks




48 Artificial Selection

49 Sources of Variation in Population
100’s of breeds of dogs…1 species, demonstrates the tremendous potential for variation …extent of variability, is a major determinant of capacity for evolution






55 Balanced Polymorphism
Two phenotypes in one species, each better for its own environment


57 Mutations Provide new alleles in gene pool Adaptations

58 Sexual Reproduction Provides variation

59 Independent assortment of chromosomes

60 Crossing Over

61 Random Fertilization A zygote is formed by the random union of independently-produced gametes. For humans, the number of different gametes is 223 * 223, or 8,388,6082, giving 70,368,744,177,664 (70 trillion) possible combinations.

62 Outbreeding Mating organisms that are not closely related….
Is that bad or good?

63 Promotion of Outbreeding
Flowering plants..male and female parts mature at different times Lions---dominant male chases away young maturing males…

64 Diploidy 2n condition, whole other set of genes that could be an advantage when conditions change

65 Heterozygote superiority
Hybrids have an advantage ** Population retains greater variation Ex sickle cell anemia Ss- no sickle cell, and resistance to malaria SS no sickle cell, die from malaria ss has sickle cell, and may die from that


67 Frequency Dependent Selection
Minority advantage Decrease frequency of more common phenotypes Ex.) Search image….predators are used to chasing prey that looks a certain way, if you look different you and your young will survive…

68 Evolutionary Neutral Traits
Bloodtype Fingerprint variation Where from? Why? Function? ….all unknowns

69 Causes of Evolution Genetic Drift: change due to chance
Bottleneck effect (fire, earthquake, flood)…


71 Founder effect

72 Small population breaks away from a larger one
Small population breaks away from a larger one. Rarer alleles are over represented….. Amish 1770’s German population, extreme isolation, and intermarriage


74 Gene Flow Movement of alleles in or out of population Migrations

75 Mutations Changes in genetics material

76 Nonrandom mating Individuals chose mates for a specific reason

77 Natural selection Environment changes
Those who are better adapted to it “are selected for” They survive They reproduce and those genes are passed on…

78 Sources of Stability in populations
Hardy and Weinberg Stable population would require 5 things large Isolated No mutations Mating random No natural selection

79 This is purely hypothetical, it CANNOT exist

80 Hardy Weinberg Equation
Calculate frequencies of alleles in population P dominant allele Q recessive allele Problems 1, 2, 3 – go over together


82 Speciation To be of the same species….
Potential to interbreed in nature Produce fertile viable offspring

83 Allopatric speciation
Caused by geographic isolation


85 Sympatric Speciation Polyploidy- more than 1 set of chrom
Habitat isolation- Behavioral isolation Temporal isolation Reproductive isolation

86 Plants that are polyploidy CANNOT breed with plants that have the normal number of chromosomes

87 Habitat Isolation

88 Behavioral Isolation

89 Temporal Isolation

90 Reproductive Isolation
Anatomical incompatibility Small male dog and large female dog cannot mate Prezygotic barriers- prevent mating Postzygotic barriers- mating occurs but offspring is infertile



93 Patterns of Evolution Divergent

94 Convergent

95 Convergent

96 Parallel Evolution

97 Coevolution

98 Adaptive Radiation

99 Macroevolution Gradualism- organisms descended from a common ancestor gradually, in a linear and branched fashion. Prob: A lot of missing links haven’t been found

100 Punctuated Equilibrium
Gould and Eldridge- new species appear suddenly after long periods of stasis… See figures page 183

101 Origin of Life Earth age 4.6 billion years
Ancient atmosphere, had many gases but lacked free oxygen UV rays and lightening Mimicking early Early Earth….

102 Mitochondrial DNA, is inherited from the mother…..

Download ppt "Chapter 9 Evolution Barron’s Book."

Similar presentations

Ads by Google