1. More Than An EyeWitness
Evidence for Evolution

2. Sources of Evidence From observation From studies of embryology
Biochemistry
From the fossil record
From studies of DNA
From studies of anatomy

3. EVIDENCE FROM FOSSILS
From the fossil record

4. Transitional Organisms
If evolution has occurred in the past there should be evidence of transitional organisms in the fossil record.

5. Archeopteryx
Archeopteryx shows evidence of the evolution of birds from reptiles….there is evidence of feathers, a characteristic of birds, and claws, a characteristic of reptiles.

6. EVIDENCE FROM ANATOMY
From studies of anatomy

8. Did you write down all your Guesses? IF SO: CLICK!!!!

10. Did you write down all your Guesses? IF SO: CLICK!!!!

11. Identify how each organism uses its forelimb
Frog
Lizard
Bat
Human
Lion
Sea Lion
bird
balance
Walking
flying
Multiple
uses
walking
swimming

12. Anatomical Studies show
Homologous parts – similar in structure but not necessarily function – evidence of evolution from common ancestor
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13. Anatomical studies show...
Name two other organisms that have the ability to fly but have wings very different than those of the bird or the bat?

14. Analogous structures
Butterflies or insects have wings but they are very different from the birds. These organisms do not have a common ancestor but have adapted to a similar environment. Again evolution explains the similarities.
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15. Anatomical studies show
Vestigial parts – why does a whale have a pelvis and femur bones if it has no hind limbs?

16. Vestigial structures
Why does this salamander have eyes if it never sees the light of day?

17. Vestigial structures

18. Did you write down all your Answers? IF SO: CLICK!!!!

19. Why do these structures occur?
These structures may be homologous to ones that had a function in the ancestors of these organisms thus suggesting their evolution from this common ancestor.

20. Anatomical Studies
Anatomical studies of cells show a commonality in structure of the cell membrane among almost all living things. Does this suggest a common ancestor for all life?

21. EVIDENCE FROM EMBRYOLOGY
From studies of embryology

22. Embryology Studies
Even though it may not be apparent during the first stage (A) these five organisms are very different when born and at later stages of embryonic development. Why do they look so similar initially?
Stage
(A) A B C D E
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23. Did you THINK about it. Did you write down all your Guesses
Did you THINK about it? Did you write down all your Guesses? IF SO: CLICK!!!!

24. Embryology Studies The organisms are: Fish Salamander Chicken Rabbit
Human
Why would these five, so different looking organisms at birth, look so similar before birth?

25. More about embryological studies

26. EVIDENCE FROM BIOCHEMISTRY

27. Studies of Biochemistry
Species
Sequence of Amino Acids in the Same part of the Hemoglobin Molecule
Human
Lys-Glu-His-Iso
Horse
Arg-Lys-His-Lys
Gorilla
Lys-Glu-His-Lys
Chimpanzee
Zebra
Arg-Lys-His-Arg

28. Which organisms appear to be more closely related to each other?
Human and chimpanzee have no differences in their amino acid sequence suggesting their close evolutionary relationship, they have a more recent common ancestor. Studies of other chemicals, like proteins used in digestion, show similar comparisons in these organisms.

29. EVIDENCE FROM DNA
From studies of DNA

30. DNA
From studies of DNA
The sequence of the nucleotides making up their DNA would also be similar because DNA determines the sequence of amino acids in proteins.

31. DIRECT OBSERVATION OF EVOLUTION OCCURRING IN MODERN DAY ORGANISMS
From observation

32. Observations of Evolution in modern organisms
Mosquitoes resistance to insecticides
Bacteria resistance to antibiotics
New strains of Plasmodium that cause Malaria
New strains of TB (tuberculosis)
Peppered moth
Darwin finches

33. Has and Does Evolution Occur?
Scientists do not dispute that evolution does occur. Evolution is a FACT.
How evolution occurs is not completely understood.
Charles Darwin explained how evolution occurred through natural selection. Natural selection is a well documented THEORY uniting all of biology.
Modern evolutionary theory uses ideas of genetics, particularly mutations, to help explain how evolution may occur. (Darwin didn’t know about mutations.)