1. Darwin’s Voyage Objectives:
Predict why certain traits are more likely to offer an advantage for survival of an organism.
Cite examples of Traits that provide an advantage for survival in one environment but not other environments.
Relate the structure of organs to an organisms ability to survive in a specific environment.

2. Vocabulary Write the definitions to the words as we talk about them.
1. Scientific Theory-
2. Evolution-
3. Species-
4. Natural Selection-
5. Variation-
6. Adaptation-

3. HMS Beagle Sets Sail 1831 5 year world trip Charles Darwin 22
Ships naturalist
noticed big difference in plants and animals
developed Scientific Theory ‘Evolution by Natural Selection’

5. South America

6. Argentina
Armadillo Sloth

7. Darwin amazed at diversity
More diverse than ever thought-currently 1.7 million species.
puzzled : bones of dead large animals looked like small animals of present.
Why only smaller sloths alive today?

8. Galapagos Islands

9. Similarities
Galapagos Is Mainland S.A.
same same

10. Differences Galapagos Mainland S.A. Island #1 Island #2 no fly fly
large claws/ small claws/
slippery rocks leaves on trees
Island #1 Island #2
dome shaped shell saddle shaped

11. Mainland animals somehow got to island Offspring became different than relatives

12. Beaks of Finches suited to life it led.
insects
sharp beaks
seeds
strong, wide
Adaptation- a trait that helps
an organism survive and reproduce.

13. 20 years of Thinking
“Perhaps, the species gradually changed over many generations and became better adapted to the new conditions.”
evolution- gradual change in a species over time.
Darwin’s ideas are ‘Theory of evolution’.
Scientific theory – a well tested concept that explains a wide range of observations.

14. Man-made selective breeding
English farmers fine wool
Darwin pigeons large fan tail
Nature ???????

15. 1858 The Origin of Species
-evolution occurs by natural selection- process by which individuals that are better adapted to their environment are more likely to survive and reproduce than other members of the same species

16. Natural Selection Factors
Sea Turtles
100 eggs
all survive
full of turtles
not enough resources
not enough to eat
not able to escape predators
new fast predator
fast turtles escape
Reproduce- fast swimmer trait
environment has selected helpful traits
unfavorable traits disappear
Overproduction
Competition
Variations- any difference in traits between individuals of same species

17. Other adaptations Teeth:
Animals Pgs
Teeth:
broad, flat surface, grinding (grasshoppers, termites, snails, cows, horses, pandas)
sharp, pointed, stabbing, cutting (wolves, frogs)
some sharp in front, flat in back (grizzly bears, humans)
Birds pgs
Plants pgs
Herbivore
Carnivore
omnivore

18. Escape Variations Hard shells spiny skin play dead stingers claws
bitter taste
smelly sprays

19. No variation = Everything stays the same
Mutations in genes or allele shuffling bring variation
only genes from inherited traits can be acted upon by natural selection
Darwin didn’t understand all this, but knew somehow it was connected

20. Evolution in Action finch beak size changes due to natural selection
1977
Daphne Major
Galapagos Is.
25 ml. rain
Plants died
Following year
finches had
large stronger
beaks
Fewer small
seeds
available
Small beak
finches
didn’t survive
drought
Evolution by natural selection in 1 year
Ate large
seeds in tough
thorny pods
Finches w/ large
strong beaks could
open pods
-not smaller weak,
beak finches

21. Evolution of Peppered Moth
1700’s English Peppered Moth
light gray
Natural selection
favored black moths
Birds could only
see black peppered
moth against light gray
trees
1850
most peppered
moths were black
Industrial Rev.
smoke blackened trees
Gray moth easy
to see now
Birds ate
gray moths

22. How do new species form?
Geographic isolation-members of species get cut off from rest of species and can no longer mate with them and evolve with different traits than the original group.
Ex: river, volcano, Mt. Range, ocean wave.

23. 10,000 y.a. they were the same species !
Aberts
Kaibab
Isolation in forest N. of Grand Canyon Az.
Might have evolved to a new species.

24. Geographic Isolation on a Worldwide scale -Organisms able to migrate to all places before continents separate -Species become isolated -Species in each area evolve independently

25. Australia -isolation brought marsupials

26. Natural Selection

27. Vocabulary Matching
1. Scientific theory a. Similar organisms that can mate with each other and produce fertile offspring.
2. Evolution b. A trait that helps an organism survive and reproduce.
3. Species c. Gradual change in a species over time.
4. Natural selection d. A well-tested concept that explains a wide range of observations.
5. Variation e. Individuals better adapted to their environment, able to survive and reproduce than other species.
6. Adaptation f. A difference between individuals of the same species.