1. Evolution
Unit 10

2. Darwin and Evolution

3. Charles Darwin Naturalist 1809-1882
Traveled on HMS Beagle for 5 years (22 yrs old)
Galapagos islands- unique animals like the turtles and finches found there
Travel and observations lead to Darwin's ideas………

4. Influences on Darwin
Hutton: Earth is shaped by geologic forces- older than millions of years
Lyell-processes on Earth have been happening for a long time and these processes have shaped the Earth’s geologic features
Lamark-use and disuse,inheritance of aquirred traits
Malthus-human population will grow faster than raw materials can be produced

5. Natural Selection
Explanation of how populations change over time ( a very long time)
Another way to say this:
Survival of the Fittest- those organisms within the group have some sort of variation that allows them to survive and produce offspring with the same variation

6. For all populations these factors must exist for natural selection:
Organisms overproduce- more babies born than will actually survive
Variations exist within the species- example: fish scale color
Variations passed on to offspring
Overtime the population changes to exhibit the favorable variations

7. Artificial selection
Humans select desired traits
Dog breeds

8. Descent with modification-each living species has desended with changes from other species over time.
Common descent-all species derived from common ancestor

9. Evidence of Evolution Seen in:
Structural changes
a. camouflage- blend into surroundings
b. mimicry- look like another organism with a favorable trait
Physiological changes- metabolism
ex. Drug resistant bacteria

10. Camouflage Mimicry

11. We can see the changes by showing relationships between organisms
1.Fossils-
a. molds (left behind by soft tissue)
b. bones

12. 2. Anatomy-look at structures
a. homologous- similar in arrangement and/or function

13. b. Analogous – similar in function but not in structure

14. C. Vestigial- organ or structure not used any more like our appendix
C. Vestigial- organ or structure not used any more like our appendix. Do you know what animal has a working appendix?
RABBITS
Other examples:
Molars in vampire bats
leg bones in snakes and whales
ear muscles in humans

15. 3. Embryology- study of embryos. Look for similarities.

16. 4. Biochemistry-horseshoe crab biochemistry more similar to spiders than other crabs.
5. Geographic distribution-similar animals develop in different areas due to common conditions.

17. www. ngm. nationalgeographic. com/ngm/0411/f eature1/multimedia/index
eature1/multimedia/index.html

18. Population Genetics Gene pool- # or % of alleles in a population
Allelic Frequency- % of a specific allele in a gene pool. (Ex.- how many B’s or b’s in the classroom)
Do populations change? YES!!!!
Genetic Equilibrium- no real change in allelic frequency of population

19. Ways a Population Can Change
Mutation- (in gametes)
Sexual reproduction
Genetic Drift- alteration by chance event like an earthquake, fire, flood-change in allelic frequency
Gene Flow- movement in or out of organisms in a population. Ex. All the people with blue eyes moved to Canada- what would happen to the allelic frequency of b?
Traits controlled by a single gene will have a greater chance of differences in allelic frequency and therefore lead to change.

20. 3 Types of natural Selection Which group is favored?
Middle group- STABALIZING SELECTION
One extremes- DIRECTIONAL SELECTION
Both extremes- DISRUPTIVE SELECTION

21. Hardy –Weinberg Principle
In order to maintain genetic equilibrium:
Random mating
Large population
No movement in or out
No mutations
No natural selection

22. How do new species form?
Speciation- evolution of a new species-new group is unable to breed with old group
Behavioral isolation- wrong mating dance
Geographic Barrier- splits group and over time changes occur in one or both groups that do not allow them to breed with each other.
Reproductive isolation- 2 groups can’t mate with each other –parts don’t fit, different mating cycles (Temporal)

23. How fast does evolution occur?
Speciation Rate- speed of evolution
Gradualism- speciation occurs gradually over a long period of time
Punctuated- short quick bursts( dinosaurs)

25. The Classification of Organisms
Taxonomy
The Classification of Organisms

26. Taxonomy
Branch of biology that groups and names organisms based on similarities

27. Early Classification Systems
Aristotle started grouping plants into 3 categories: herbs, shrubs, and trees

28. Carolus Linnaeus ( )
Based his groupings according to physical and structural characteristics
Had a 2 word naming system like a first and last name called
BINOMIAL NOMENCLATURE
Used Latin because it is universal and it’s a dead language (it doesn’t change)

29. When we name organisms we usually just give the Genus and species name like
Homo sapien
Note that the Genus name is capitalized and the species name is in lower case
In print you will see the Genus and species name in italics.

30. Order of classification
Biggest to smallest
(Domain)
Kingdom
Phylum
Class
Order
Family
Genus
Species
Kings play chess on fine green sand

31. How are the groups decided?
Structural similarities
Breeding behavior
Geographical distribution
Chromosome comparison (how many bases match)
Biochemistry

32. Domains
Bacteria-prokaryotic, cell wall made of peptidoglycan,common like strep,staph
Kingdom-Eubacteria
Archaea-prokaryotic,live in extreme environment
Kingdom- Archaebacteria
Eukarya- eukaryotic cells
Kingdoms-Protista,Fungi,Plantae,Animalia

33. Domain Eukarya
Protista-animal like, plant like, fungi like, most single celled, some photosynthetic
Fungi- heterotrophs, decomposer
Plantae- multicellular, photosynthetic, cell wall
Animalia- multicellular, heterotroph