1. EVOLUTION!!!!!!
There is a grandeur to this view of life…that, whilst this planet has gone cycling on…endless forms most beautiful and most wonderful have been, and are being, evolved.
~ Charles Darwin

2. The father of evolution…
Charles Darwin (1809 –1882)
Naturalist
HMS Beagle
On the Origin of Species: 1859

3. Other evolutionary ideas…X
Other evolutionary ideas…
Lamarck – theory that use and disuse translates into inheritance
Example: A war veteran lost a limb, will his child be susceptible to the same lack of limb???
Simplicty Complexity

4. Darwin’s Theory of Natural Selection
Individuals differ – variation comes from???
Organisms produce more offspring than can survive → many do survive but don’t reproduce
* this increases competition for resources

5. Individuals BEST suited to environment at given time survive & reproduce most successfully
* Fitness – reproductive success
* Result of natural pressures → selection over time of fittest (think breeding bunnies!)!!!
Over time, offspring with certain variations make up most of population
* Over LONG time, changes in several traits can result in modified organisms → descent with modification

6. Peppered Moth Simulation
A case study…
At the beginning of the nineteenth century, most moths in the UK were an off-white color, highly adapted to hiding from predators, such as birds, by resting on pale, mottled grey tree trunks. But the Industrial Revolution polluted the environment, raining soot down on the countryside. As a result, white moths became highly visible on the now blackened tree trunks. Based on the above scenario, predict what would happen to the moth population of moths over the next several generations.
Peppered Moth Simulation

7. When we say long, we mean loooooooooooooooong…

8. Evidence for Evolution
Physiological
Anatomy
Embryology
Biochemical
Geological
Environmental variation
Plate tectonics
Fossils
Adaptations

9. Anatomy
homologous structures – features having a common evolutionary ancestry
Can be similar in structure & function

10. analogous structures – different organisms having structures with similar functions but NOT common evolutionary origin

11. vestigial structures – body structure having no function in a present-day organism, but probably had useful function in earlier ancestor

12. Embryology – look at early development of organisms for structural similarities

13. Biochemistry Compare DNA & RNA between different species
Greater the # of similar sequences, MORE CLOSELY related
Conserved sequences – sequences that appear in many organisms, help determine relationship
Ex: TATAA box & homeobox genes
**Pg 470 Analyzing Data Activity!**

14. We know about Darwin, but what else drives evolution???
Mutations
Gene Flow – shift in gene pool as individuals immigrate/emigrate
Genetic drift – changes in allelic frequencies in a population by chance events
**when alleles remain constant over several generations, population is in genetic equilibrium**

15. Homework: Conserved Amino Acid Sequence Activity
Closure…
Explain what the evidence you examined today (both environmental & genetic!) suggests about organisms over time.
Homework: Conserved Amino Acid Sequence Activity

16. Do Now
Based on what you have learned thus far, would you support the claim that the earth is ever-changing? Yes or No? Provide evidence to back up your claim.

17. Human & natural effects can result in changes in the environment over time – this can result in organism changes, so much so that they are NEW species…but how do we know when a new species has arrived?
Define: What is a SPECIES?
Group of organisms that can interbreed to produce fertile offspring

18. Genetic variation based on mutations/natural selection over several generations
Isolation – geographic, reproductive (ex: fragmentation, natural events)

19. Evolutionary Patterns
Coming together & driving apart
Divergent evolution – species that were once similar become increasingly distinct (Ex:wild cats)

20. Evidence for this? Plate Tectonics
**As Pangea separated into our known continents, organisms experienced isolation and changing climates**

21. Type of Divergent:
Adaptive Radiation – evolution of several species from one to fit a number of diverse habitats (Ex: Galapagos, Hawaii)

22. Convergent evolution – unrelated species evolve similar structures resulting from similar environmental pressures
**These 4 organisms look alike but do not share common ancestry – rather, they share similar niches – ALL eat ants, hunt in high grass, and swim in the dark**

23. Evidence beyond Darwin…
Adaptations
structural: mimicry, camouflage Monarch & Viceroy
physiological: resistance to drugs

24. Fossils
Provide record of early life
PRESENTLY INCOMPLETE!

25. Hominid Skulls

26. Phylogenetic Tree of Life

27. Is that the end of the story???
Researchers are STILL finding evidence to support the theory of evolution
Fossil record changes with each finding
….there’s a lot more to be done!
NOT