CH 14, & 15

1. CH 14, & 15 Evolution and Natural Selection

2. Theory of the beginning • Life originated in the oceans 3.9-3.4 billion years ago • Earth is approximately 4.4 billion years old • Oldest rocks are 3.9 billion years old. Rock provide evidence on diversity of life because of the fossil formation • 95% of species that have existed are now extinct • Paleontologist

3. How do fossils form? • Organism buried in mud, sand or clay soon after they die • Compressed over time and harden into rock • Sedimentary rock • Types of fossils table 14.1 page 371 • Fossilization process page 373 • Relative dating- determines the age of a fossil • Radiometric dating- determines a specific age by utilizing radioactive isotopes

4. Oldest human fossil • Discovered in 1974 in Ethiopia • “Lucy” • 3.2 million years old • Adult female • Thought to be about 25 years old at death

5. The origin of life • Spontaneous generation page 380 • Biogenesis page 381

6. The origin of life: Biology and Society • Page 388

7. Theory of evolution • Change in a population over time • Charles Darwin 1809-1882 • 1831- sailed around the world on a 5 year scientific journey • Studies finches on the Galapagos Islands. Developed theory of Natural Selection

8. Natural Selection • 1. in nature, organisms produce more offspring than can survive • 2. in any population, individuals have variations • 3. individuals with certain useful variations survive in their environment passing those variations to the next generation • 4. over time, offspring with certain variations make up most of the population and may look entirely different from their ancestors

9. Darwin wrote a book • On the Origin of Species by means of Natural Selection- 1859

10. Natural Selection Video • http://www.youtube.com/watch?v=vgIm6i-Olc4 • 6:42

11. Adaptations • Any variation that aids an organism’s chances of survival in its environment • Ex. Mimicry- page 398 • Ex. Camouflage- page 399 • *How can mimicry and camouflage cause populations to change over time????*

12. Peppered Moth Survey • HW

13. Anatomy page 400 • Comparing structural or functional similarities • Homologous structures • Analogous structures • Vestigial structures

14. Stop day 1 notes here

15. How to debate

16. In a debating team each speaker has specified roles that they must fulfill to play their part in the team. They are laid out below in the order that the speakers will speak. • 1st Affirmative must: • - define the topic. • - present the affirmative's team line. • - outline briefly what each speaker in their team will talk about. • - present the first half of the affirmative case.

17. 1st negative must: • - accept or reject the definition. If you don't do this it is assumed that you accept the definition. • - present the negative team line. • - outline briefly what each of the negative speakers will say. • - rebut a few of the main points of the first affirmative speaker. • - the 1st negative should spend about one quarter of their time rebutting. • - present the first half of the negative team's case.

18. 2nd affirmative must: • - reaffirm the affimative's team line. • - rebut the main points presented by the 1st negative. • - the 2nd affirmative should spend about one third of their time rebutting. • - present the second half of the affirmative's case.

19. 2nd negative must: • - reaffirm the negative's team line. • - rebut some of the main points of the affirmative's case. • - the 2nd negative should spend about one third of their time rebutting. • - present the second half of the negative's case

20. rebuttal • It is very important to have a good perspective of the debate and to identify what the key arguments are.  It isn’t enough to rebut a few random arguments here and there.  Of course the techniques used above are invaluable but they must be used appropriately.  There are a number of things you should do to systematically break down a team’s case:  • 1.  Ask yourself how the other side have approached the case. Is their methodology flawed? • 2.  Consider what tasks the other side set themselves (if any) and whether they have in fact addressed these.  • 3.  Consider what the general emphasis of the case is and what assumptions it makes. Try to refute these.  • 4.  Take the main arguments and do the same thing.  It is not worth repeating a point of rebuttal that has been used by someone else already, but you can refer to it to show that the argument has not stood up.  It is not necessary to correct every example used.  You won’t have time and your aim is to show the other side’s case to be flawed in the key areas.

21. rebuttal • You should have at least 15 questions that can be asked of each of your opponents. - job of “rebuttal person” • You should have answers prepared which will be used to respond to your opponents questions- job of everyone on your team • Take notes as the other team presents- it is your job to disprove them!

22. Rebuttal… • In debating each team will present points in favour of their case. They will also spend some time criticising the arguments presented by the other team. This is called rebuttal. There are a few things to remember about rebuttal. • 1. Logic - to say that the other side is wrong is not enough. You have to show why the other side is wrong. This is best done by taking a main point of the other side's argument and showing that it does not make sense. Because a lot of the thinking for this needs to be done quickly this is one of the most challenging and enjoyable aspects of debating. • 2. Pick the important points - try to rebut the most important points of the other side's case. You will find that after a while these are easier and easier to spot. One obvious spot to find them is when the first speaker of the other team outlines briefly what the rest of the team will say. But do not rebut those points until after they have actually been presented by the other team. • 3. `Play the ball' - do not criticise the individual speakers, criticise what they say. To call someone fat, ugly or a nerd does not make what they say wrong and it will also lose you marks.

23. Closing arguments • You should have a final conclusive argument/statement which is persuasive, strong and addresses the other team • Repeat the main idea

24. CUE CARDS. Do not write out your speech on cue cards. There is even a current, and indeed deplorable, trend towards computer generated cue cards. Debating is an exercise in lively interaction between two teams and between the teams and the audience, not in reading a speech. Use cue cards the same way you would use a prompt it a play, they are there for reference if you lose your spot. You can tell when someone is reading.. remember the television announcements by the politicians in the recent ACT elections? • 2 EYE CONTACT. Is very closely related to cue cards. If you look at the audience you will hold their attention. If you spend your time reading from cue cards or looking at a point just above the audience's head they will lose concentration very quickly. When you've got them by the eyeballs their hearts and minds will follow. • 3 VOICE. There are many things you can do with your voice to make it effective. You must project so that you can be heard but 4 minutes of constant shouting will become very annoying very quickly. ( Like a butcher shouting out the daily specials ). Use volume, pitch and speed to emphasise important points in your speech. A sudden loud burst will grab your audience's attention while a period of quiet speaking can draw your audience in and make them listen carefully. • 4. BODY. "Work it baby, work it!". ( Although any other links between the movie Pretty Woman and debating end here ! Your body is a tool for you to use. Make hand gestures deliberately and with confidence (a fine example of someone who can't is that idiot on the Canberra Toyota ads at the moment). Move your head and upper body to maintain eye contact with all members of the audience (although automatically moving your head from side to side makes the adjudicator want to pop a ping-pong ball in there). If you want to walk up and down do so but move with effect and deliberately, don't wear worry lines into the carpet. If you are going to stand still, stand with confidence. Don't let your body apologise for your presence by appearing nervous. • 5 NERVOUS HABITS. Avoid them like the plague. Playing with your cue cards, pulling on a stray strand of hair, fiddling with your watch, bouncing up and down on the balls of your feet or bouncing your cue cards off the nose of the nearest audience member as you are finished with them only distracts from your presentation. Use your whole person to effect, don't let any one thing detract from your ability to persuade the audience. • 6 ELOCUTION AND OTHER BIG WORDS. This is not an exercise in grammar or elocution. Try to avoid being too informal but don't go overboard the other way. There are no marks to be gained from trying to use big words you don't understand or can't pronounce. In the same way it is a huge mistake to let someone else write your speech. People that do that aren't entering the spirit or developing the skills of debating and end up looking really silly getting stuck on a word they just can't say.

25. A CREATIONIST: A creationist is a person who rejects the theory of evolution and believes instead that the each species on earth was put here by a Divine Being.  A Creationist might accept "micro-evolution" (changes in the form of a species over time based on natural selection), but rejects the notion that one species can-- over time-- become another species. • YOUNG EARTH CREATIONIST: A young earth creationist believes that the earth is nowhere near the 4.6 billion or so years old that most scientists estimate, but is instead closer to 6,000 or so years old, based on the assumption that Genesis contains a complete listing of the generations from Adam and Eve to historical times.

26. INTELLIGENT DESIGN PROPONENT: An ID proponent might or might not reject the theory of evolution.  At a minimum, the ID proponent rejects that evolution is randomly driven or, more generally, the notion that natural law and chance alone can explain the diversity of life on earth.  Instead, the ID proponent argues--often from statistics--that the diversity of life is the result of a purposeful scheme of some higher power (who may or may not be the God of the Bible). • EVOLUTIONIST: An evolutionist accepts the Darwinian argument that natural selection and environmental factors combine to explain the diversity of life we see on earth.  An evolutionist may or may not believe that evolution is the way in which a Divine Being has chosen to work in the world.  Evolutionists divide into various camps, including PUNCTUALISTS (who believe that evolution usually occurs sporadically, in relatively short bursts, as the result of major environmental change) and GRADUALISTS (who are more inclined to believe that evolution occurs more evenly, over longer periods of time). 

27. Begin notes day 2 here

28. Mechanisms of evolution- page 404 • Populations, not individuals, evolve • How can a population’s genes change over time? • Gene pool • Allelic frequency • Genetic equilibrium

29. Changes in genetic equilibrium • A population in genetic equilibrium is not evolving because allelic frequencies remain the same, phenotypes remain the same too

30. Mechanisms for genetic change • Mutation • Genetic drift • Gene flow • Natural selection is the most significant factor that causes changes in established gene pools

31. Three different types of natural selection acting on variation • Stabilizing- favors average individuals in a population • Directional- favors one of the extreme variations of a trait • Disruptive- eliminates the intermediate phenotype and favors the 2 extreme phenotypes

32. speciation • Evolution of a new species which occurs when members of similar populations no longer interbreed to produce fertile offspring within their natural environment

33. Geographic isolation • Occurs whenever a physical barrier divides a population. A new species can evolve when a population has been divided this way

34. Reproductive isolation • When formerly interbreeding organisms can no longer mate and produce fertile offspring

35. Diversity in new environments • Adaptive radiation • Divergent evolution • Convergent evolution