1. Change over a period of time.
Evolution
Change over a period of time.

2. Biodiversity The variety of organisms, the genetic information they contain, and the biological communities in which they live.
Ecosystem Diversity
The variety of organisms, the genetic information they contain, and the biological communities in which they live.
Species diversity
The number and variety of species on Earth.
Genetic Diversity
The different forms of genetic info carried by all organisms living on earth today.
Gives rise to inheritable variation, the raw materials for evolution.

3. Charles Darwin Sailed for 5 years on a ship called the Beagle.
Made and documented many observations of living things over 5 years.

4. Charles Darwin
The Naturalist who first made the hypothesis about the way life changes over time.
Observations that caused him to make this conclusion were made while on a voyage around the world on a ship called the H.M.S. Beagle.

5. Charles Darwin
Darwin’s hypothesis was also shaped by new information about the world.
Darwin’s original hypothesis is supported by a huge body of evidence and is now a theory.

6. Darwin’s Observations on the Beagle
Large number of different species.
Plants and animals are very well-adapted to environment.
Variety of ways to survive and reproduce.
Distribution of animals is not only determined by ecosystem type.
How many species had gone extinct.

7. Darwin’s Observations (cont.)
Fossil Diversity
Collected bones and other traces of life.
Where did all of the organisms come from and where have they gone?
Fitness
The ability of an individual to survive and reproduce, thereby passing on copies of its genes to offspring.
Living Diversity
Darwin found a great variety of living creatures.
How did this diversity come to be?
Adaptation
Physical and behavioral traits that enable organisms to survive.
Darwin noted how well suited organisms were to their environment.

9. Galapagos Islands
His studies from the Galapagos Islands triggered Darwin’s thought.
Animal life on one island was distinct and different from those on other islands.
One could identify the island that a bird was from by looking at it, for example.

10. Galapagos Islands
1. Darwin wondered if the now separate species had once been of the same species, but had evolved differently when isolated from one another.

11. Darwin began to question the idea of all species remaining the same for several other reasons as well:
2. Homologous Structures
Similar structures but in different organisms that developed from similar tissues in early development.

12. Homologous Structures

13. Darwin began to question the idea of all species remaining the same for several other reasons:
3. Vestigial Structures
Structures that serve little/no purpose to the organism ( Example: Human tailbone).
4. Evidence that the earth was older than it was thought at that time.
5. Organisms produce more offspring than can actually survive.

14. Darwin’s Discoveries at Home
1. Although they looked different, birds from different islands of the Galapagos were of the same type, finches.
2. Darwin found the same of tortoises, marine iguanas, and plants from the islands.
3. He also found that island species resembled species from the mainland.

15. The Origin of Species by Means of Natural Selection…by Charles Darwin
Provided evidence in support of the idea that life has changed, or evolved, over time.
Gave an explanation of how and why evolution occurs.

16. Genetic Diversity Acted on by Natural Selection
Mutation
Change in genetic sequence that can sometimes change the characteristics of a organism.
Gene Shuffling
The shuffling of genes that occurs during the production of egg and sperm
Adaptation
A genetically controlled trait that increases an individuals ability to pass along copies of its genes.

17. Natural Selection
Nature selects the most fit (well adapted) individuals to survive.
A better adapted organism is more likely to survive to reproduce and pass on its genetic information.
Over time, these adaptations will become more and more common in a population.

18. Some mutations change organism's characteristics.
Mutations occur
Some mutations change organism's characteristics.
Bad
Characteristic
Good
Characteristic
Individual does
not reproduce
Individual
Reproduces
Trait becomes
less common
Trait becomes
more common

19. Common Descent (a.k.a. The Evolutionary Theory)
Modern day organisms are the result of the slow process of evolutionary change.
All species have descended from other species over time.

20. Speciation Speciation Species The formation of new species.
A population must evolve enough genetic changes(2 separate gene pools) so that breeding cannot occur between the emerging, genetically different groups. This is “Reproductive Isolation” vs. Darwin’s Finches: “Geographic Isolation”
Species
A group of similar looking organisms that can breed with one another and produce fertile offspring.

21. Evolutionary Tree/Cladogram A diagram that depicts the origin of new species.

22. Gene Pool Genetic Drift
The group of alleles that is shared by members of the same species.
The alleles in a gene pool will occur at a particular relative frequency unless under pressure by natural selection.
Genetic Drift
The random change in allele frequency of a gene pool

23. Pace of Evolution Gradualism Punctuated Equilibrium
Slow and steady evolutionary change.
Punctuated Equilibrium
Quick periods of great evolutionary change followed by long periods of stasis.

24. Gradualism vs. Punctuated Equilibrium
TIME

25. Adaptive Radiation
Organisms of common ancestry evolve distinct adaptations to suit a particular niche.
This pattern of evolution yields homologous structures.
Example: Darwin’s Finches beaks were adapted to eating different foods

27. Convergent Evolution
The pattern of evolution when unrelated species may independently evolve superficial similarities because of adaptations to similar environments.
This pattern of evolution yields analogous structures - those which are similar in function and appearance, but developed from anatomically different parts because of separate ancestry.
Example: Birds, bats, and insects all have wings, although the wing structure of each is very different.

28. Analogous Structures

29. Evidence Supporting Common Descent
Fossil Records
Fossils of many organisms have been found of organisms that do not exist today.
Many current organisms are similar to very old fossils and fossil links often exist between them.

30. Evidence Supporting Common Descent
Embryonic Development
Similar stages of embryo development occur in different organisms.
Organisms with similar developmental stages are considered to be closely related from an evolutionary standpoint.

31. Evidence continued Similar Proteins
Proteins are responsible for most all body functions.
Similar proteins are produced in different organisms.
Organisms that have similar proteins are considered to be closely related from an evolutionary standpoint.

32. Evidence continued DNA
Similar DNA sequences in different organisms point to close relation.

33. Molecular Clocks
Because the simple mutations in DNA should occur at a somewhat constant rate, scientists use DNA evidence to estimate the time that different species branched from a common ancestor.

34. REVIEW
Question:
By what method does evolution occur?

35. Answer:
Natural Selection

36. REVIEW
Question:
What term describes structures in different organisms that are similar in structure and were developed from similar tissues?

37. Answer:
Homologous Structures

38. REVIEW
Question:
What term describes a mutation that increases an individuals ability to pass along copies of its genes?

39. Answer:
Adaptation.

40. REVIEW
Question:
Name the scientist whose work formed the basis for the Theory of Evolution?

41. Answer:
Charles Darwin

42. This is a section for you to write in on the big open spot on your notes
Other scientists who influenced Darwin
Hutton and Lyell
Earth was very old.
Earth had changed very slowly over time.
Processes that changed Earth in the past are the same as those at work today.
Lamarck
Life had changed over time.
(his hypothesis about how was incorrect)
Malthus
Organisms produce more offspring than can survive.

43. An individual cannot evolve. Evolution can only occur in a population.
Natural selection is survival of the most well-adapted, not always the “fittest”.
Mutations are random. Some are beneficial, but most are not.
Many mutations would be required to produce new species.
Evolution occurs over hundreds of thousands of generations and requires a great deal of time for most populations.