1. Evolution
To see where we might be going, we must understand where we have been
Robert Tamarkin, 1993

2. Definition? Theory supported by evidence
Biological evolution concerns changes in living organisms during the history of life on earth.
Sharing of common ancestors
Darwin term: descent with modification

3. Branched Tree of Life
with a common
ancestor

4. Formation of the Earth 4.6 billion years old
Universe 13.7 billion years old
Complex: but woven out of 30ish main molecules – oxygen, hydrogen, carbon, nitrogen, Sulphur and phosphorus. (evidence #1)- present in early Earth- amino acids, RNA, DNA, Phosphorus, ATP
Collision Theory and gravity.

5. Evidence of Evolution

6. Earth is Old: Fossils
Fossils: the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.
record shows changes in organism over the past
3.6 billion years.
Transitional species – show the link between an ancestral form and that of the descendants (many examples)

7. Generally older fossils are lower in the strata
Changes begin from simple to more complex
First Life Form – simple cells – fossil evidence 3.4 billion years ago
Generally older fossils are lower in the strata

8. Fossil Record Supports Evolution
Millions of fossils have been discovered
Fossil record shows changes of organisms through time from simple to more complex.
Documents the order of appearance of groups and types of organisms
Transitional Species show transitions from fish to tetrapods (fish to salamanders, salamanders to reptiles), dinosaurs to birds, proto-horses to horses , apes to human, synapsid to mammals.
Document major crises in Earth’s history and the recovery from events.

9. Example of transitional species- Whales
Meet the transitional species

11. From Land to Water
Tiktaalik – 375 million years ago – Out of the soup- Whales represent a return to water (50 million years ago) Tiktaalik – out of the water.
Features- flexible neck, limb-like fins suitable for shallow waters and land

12. Oxygen Environment
What type of organisms increased in numbers to pump oxygen into the air?
Photosynthetic
Red beds
Luckily- happened slowly 2.7 to 2.0

13. Radiometric Dating

14. Radiometric Dating
*Fossils show relative dating by comparing data in the rock strata
*Radiometric Dating ability to use absolute dating - done by comparing proportions of radioactive isotopes in the sample.
* Radiometric Elements are unstable (called parents) and they decay into different elements (daughter elements). Uranium to lead.
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15. Earth’s oldest crustal rocks – 4.03 billion years old.
Oldest metamophised sediment – zircon crystals found in Canada billion years old.

16. Radiometric Dating Supports Evolution
many naturally-occurring elements are radioactive and they break down, or decay, at known predictable rates.
isotope pairs are useful in dating the Earth such as rubidium/strontium, thorium/lead, potassium/argon, argon/argon, or uranium/lead, all of which have very long half-lives, ranging from 0.7 to 48.6 billion years.
Subtle differences in the relative proportions of the two isotopes can give good dates for rocks of any age.
Dates are often cross-tested using different isotope pairs.
Results from different techniques, often measured in rival labs, continually confirm each other.
Repeatable results

17. Natural Selection

18. Charles Darwin
Not exactly a star student, but he revolutionized the scientific view of the natural world with his Theory of Natural Selection
Traveled on the Beagle where his journey began in 1831 for a 5 year voyage
The Beagle traveled from Europe to the Galapagos Islands then to Australia around the Cape of Good Hope and back to Europe

19. Observations aboard the Beagle
Species vary globally
a. Two similar species live in different areas of the world
Species vary locally
a. Differences among tortoises in the Galapagos islands
Species vary overtime
Fossils of extinct animals looked similar to living animals

20. Putting the pieces together !
Some of the species Darwin noted had never been identified before
There were similarities between the finches on the Islands when compared to the ones in South America.
What could it be????

21. Natural Selection
Natural Selection: Organisms best suited to their environment survive and are able to produce offspring
Fitness-How well an organism can survive
Adaptation- Any heritable characteristic that increases an organisms ability to survive

22. Conditions Necessary for Natural Selection
Overpopulation- individuals in a population have a capacity to produce more offspring than the environment can support
Variations – size, form, speed, camouflage
Struggle for existence – competition
Those best suited to the environment will survive and pass along their characteristics to their offspring.

23. Directional Selection
Most common
Peppered Moths in England and the Industrial Revolution
Antibiotic resistance in bacteria and the use of antibiotics
Pesticide resistance in insects

25. Directional
Selection –
depends on the
Rainfall
Seed Size increases during drought- Favors larger beaks

26. Allele Frequency Changes
Peppered Moths During the
Industrial Revolution in
England
Dark Color is Dominant
Show a change over time in
three generations following
darkening of the trees

27. Antibiotic Resistance
Antibiotic-Resistant Mycobacterium tuberculosis (TB)
Methicillin-Resistant Staphylococcus aureus (MRSA)
Vancomycin-Resistant Enterococci
(VRE)
Neisseria gonorrhoeae (Gonorrhea)
Clostridium difficile.
Gram-negative Bacteria.

28. Stabilizing and Disruptive Selection
Stabilizing – intermediate phenotypes selected *Examples – Human birth weight Plant height
Disruptive Selection – two extreme phenotypes selected
Darwin’s Finches – Example - short beak birds and long beak birds were able to eat different types of foods.
Disruptive may result in speciation

30. Disruptive Selection
Extreme phenotypes are selected for by the environment
Example: African Finches – Large and small beaked birds have a higher survival rate than intermediate (environmental force – food availability)

32. Artificial Selection
Artificial selection is when nature provides the variation amongst a species and human select the traits that they find most useful.

33. Table Buddy Collaboration
Describe a situation and follow the steps of natural selection
Overpopulation
Variation of one adaptation – size, strength, speed, color, etc.
Describe the struggle for existence and the outcome of the adaptation with the best fitness after three generations- include genotypes and phenotypes in your depiction.

35. Comparing anatomy
Homologous Structure: structures that are shared by related species and that have been inherited from a common ancestor

37. Table Buddy Colaboration
Research for 5 minutes examples of homologous structures – list in your notes
Come up with a reason why homologous structures support the theory of evolution.- explain in your notes.

38. Analogous Structures
When the function is common but the structure is different and example of this is the wing of a bird and the wing of a butterfly.

40. Vestigial Structures
inherited from ancestors but have lost much or all of their original function due to different selection pressures acting on the descendent

41. The Process of Speciation
Species – population-members can interbreed and produce fertile offspring
speciation-formation of new species

45. Green algae evolution to land plant draw a picture and explain process
Table Buddy Collaboration
Green algae evolution to land plant draw a picture and explain process

47. Molecular Evidence of Evolution

49. Other Supports
All organism are cellular – membranes filled with water – genetic material, proteins, lipids, carbs, salts, etc.
Most organisms use sugar for fuel in s similar process
-proteins as building blocks and messengers- same amino acids to make them

50. Only three differences in plants and animal cells

51. Amino Acid Differences in Cytochrome c (CR)
Organism
Number of amino acid differences
Human
Chimpanzee
Rhesus monkey 1
Rabbit 9
Pig 10
Dog
Horse 12
Moth 24
Yeast 38

53. DNA Similarities

54. Collaboration – One Minute Summary 
Discuss with your table buddy what you would like to summarize as evidence of evolution covered in this unit – must include examples, all evidence presented. I will have you summarize in a 30 second to one minute summary -

55. Descent with Modification
A shared character is one that two lineages have in common, and a derived character:  character the sets the group
Examples of derived characters
Amniotic egg, lungs, vertebral
Columns, etc.