1. TOPIC: Evolution AIM: What are the theories about Evolution?

2. AIM: What evidence supports the theory of evolution? DO NOW:
TOPIC: Evolution
AIM: What evidence supports the theory of evolution?
DO NOW:
Which layer
contains the:
Oldest fossils
Youngest fossils A B C D E

3. What do goosebumps have to do with evolution?
Our ancestors were warmer when they “fluffed up” their hair which is easily observable in modern day birds and mammals. Goosebumps may have evolved to “fluff up” the hair or fur on a hairy or furry mammal ancestor to insulate themselves against the cold. Now we have so little body hair, it is useless for insulation purposes.
It's not so much that humans evolved goosebumps. Our ancestors evolved them while they still had fur. Over time, evolution caused us to lose our fur,We lost the fur, but not the muscles connected to the hairs.

4. The hair stands up on the backs of our necks when we are afraid
The hair stands up on the backs of our necks when we are afraid. What does this have to do with evolution?
Our ancestors looked bigger when they were frightened if their hair stood up. This also can be seen in cats and even chimpanzees.

5. Improves chance of survival Ex: Camouflage
adaptation
Inherited trait
Improves chance of survival
Ex: Camouflage

7. Ducks are birds that have waterproof feathers
Ducks are birds that have waterproof feathers. They live on a pond and on land.

8. Kangaroos
Habitat: Dry inland Australia, including deserts and grasslands
Adaptations:
Able to go without drinking as long as green grass is available
Adapts well to drought.
Hop as fast as 40 mph (first line of defense)
Tendon in the leg which acts like a rubber band (conserves energy)
Tail for balance when the animal leaps and as a prop when it stands.

9. Gorillas Habitat: Tropical forest Adaptations:
Opposable thumb enables manipulation of objects
Big toe opposable for grasping.
Large and powerful arms to break stalks or uproot vegetation while foraging.
High intelligence probably an adaptation for finding scarce or isolated fruit plants in the rain forest.

10. Cactus Habitat: Dry deserts Adaptations: Spines:
Protection from hungry and thirsty animals.
Shade
Windbreak to prevent dehydration from dry winds
To help trap warm air close to the plant.
Root systems very close to the surface of the soil  take advantage of the slightest rain shower.

13. Charles Darwin 1830’s Galapagos Islands
(off South America’s west coast)

14. Natural Selection
Organisms born with favorable adaptations would be better able to survive & reproduce than those with unfavorable ones

15. He was amazed by the variety of life on the islands.
Darwin’s Model of Evolution
He was amazed by the variety of life on the islands.

16. Hypothesis: The plants & animals on the islands originally came from Central and South America.
But the islands were home to many species he had not seen in South America.

17. Darwin observed 13 species of that were similar except for differences in body size, beak shape, and eating habits.

18. He noticed that all finches were similar to 1 finch he saw on the South American coast.
Darwin reasoned that the Galápagos finches must have had to compete for food.

19. Finches with beak shapes that let them eat food survived longer & reproduced more than finches without those beak shapes.

20. After many generations, these groups of finches became separate species.

22. Main Points of Natural Selection

23. Reproduce more offspring than can survive1.
Overproduction
Reproduce more offspring than can survive
Better adapted  survive & reproduce

24. 2. Competition Limited resources  compete 
more adapted will survive & reproduce

25. 3. Variation Differences in the same species 
better adapted will survive & reproduce

26. Ex: Polar bears with thicker fur
How do variations occur?
mutations & sexual rep

29. Those most “fit” (with favorable adaptations) will survive & reproduce4.
Survival
Of the
Fittest

30. 5.
Speciation
New species form bc favorable adaptations stay & unfavorable disappear

34. REVIEW: Give an example of an adaptation found in an organism.
What is natural selection?
Give an example of a variation within a species.
What causes the greatest variation within a species?
How does overproduction lead to natural selection?