1. Evidence of Evolution
Blue-footed booby

2. Part 3: Evidence of Evolution What supports the Theory of Evolution…..
Five Fingers of Evolution - video
Part 3: Evidence of Evolution What supports the Theory of Evolution…..

3. Evidence of evolution Fossil Record Anatomy Embryology Biochemistry
Evidence in microevolution

4. Preservation (insect in amber)
Fossil evidence
Mold Fossil
Fossils → remains of ancient life
Fossils arranged according to age show a progression of changes
The Law of Superposition → a layer of rock is older than the layer above
Fossils can be arranged by relative age
Radioactive Dating → naturally occurring radioactive substances decay at a known rate
Transitional forms of fossils are evidence for evolutionary change
Preservation (insect in amber)
Cast Fossil

6. Reasons Why a Fossil Might Not Form
Dead bodies may be eaten or scattered (scavengers)
Decay
Hard exoskeleton vs. soft-bodied organism

7. Anatomy evidence
Evolution works primarily by modifying pre-existing structures
Homologous structures: parts came from the same origins, but now may have different function
e.g., forelimbs of all mammals contain the same pattern of bones, although the bones now carry out a variety of functions
horse leg, bat wing, human arm, whale flipper

9. Anatomy evidence
Analogous structures: parts came from different origin, but now have same function

10. Anatomy evidence
Vestigial structures: parts have no current function (had a function in ancestors)
Examples in humans: wisdom teeth, erector pili, coccyx, ear muscles, appendix

12. Embryology evidence
Closely related organisms develop similarly, especially in early fetal stages
This suggests that these organisms are related to other forms.
Mammal embryos (including humans) have fish-like gill slits, tail

17. Biochemistry evidence
All organisms share certain biochemistry
Genetic code for building amino acids
All organisms use ATP for energy
Plasma membranes of all organisms consist of a phospholipid bi-layer
Finding similarities in protein and DNA sequences to look for relatedness
Below is a DNA sequence in several different organisms…which organisms are the most related?
Human
CCA   TAG   CAC   CTA
Pig
CCA   TGG   AAA   CGA
Chimpanzee
CCA   TAA   CAC   CTA
Cricket
CCT   AAA   GGG   ACG

18. # of amino acid differences between human hemoglobin and other organisms

19. Evidence for Microevolution
Evolution Observed
Evolution of pesticide resistance in response to selection.

20. Evolution in Action

21. Macroevolution
Large scale changes that take place over a long period of time that create and eliminate species.

22. Microevolution
Short time scale events (generation-to-generation) that change the genotypes and phenotypes of populations.

23. Part 4: Types of Natural Selection

24. Example of Natural Selection
Nature Chooses: Individuals that survive in nature will live long enough to reproduce.
This means that they are the ones that get to breed and their characteristics (being good survivors) are inherited by their offspring.

25. Types of Natural Selection:
A) Stabilizing Selection = individuals with the average form of a trait have the highest fitness. It is favored and most common
B) Directional Selection = one extreme form of trait is more successful
C) Disruptive Selection = BOTH extreme forms are more successful than the average. The most extreme form of a trait is favored and becomes most common.
Evolution in the Big City

27. Females choose mates based on certain traits
D) Sexual Selection
Females choose mates based on certain traits
Males with these traits have higher fitness (reproductive success)
Male birds show off their beauty to attract females 
Sexual selection in humans
Video 27

28. Example of Artificial Selection
Humans Choose: Individuals that are allowed to breed are chosen by humans.
These individuals have the characteristics that humans want.
This process produces animals that express specific characteristics.

29. Is there “unnatural selection?”
Artificial Selection = humans “select” certain characteristics in plants, dogs, etc., that they find favorable
These organisms may not necessarily survive and reproduce better in nature

30. Artificial Selection
It has led to offspring through successive generations that can be very different in appearance and behavior from their distant ancestors.
Organisms with certain traits are bred repeatedly until population has only that trait
Example- Dogs, Corn, Broccoli, Cows, etc.
Creating the Perfect Pet - Video

31. Artificial Selection

32. These chickens cannot stand or move.

33. Cow selectively bred for extra meat (muscle)
Cow selectively bred for extra meat (muscle). Usually cannot stand for more than a few minutes or walk more than a few steps.

34. Artificial Selection
Selective Breeding - Video