1. Natural Selection

2. What’s for dinner
1. Take the pink sheet of paper and lay it on your desk. 2. Dump some of the Ziploc bag of dots onto the white paper. 3. Spread the dots out evenly so that they do not overlap each other.

3. What’s for dinner
4. Take the tweezers and get ready to pick up as many dots as you can. 5. Your table partner will time you for 15 seconds. Pick up as many dots as you can with the tweezers and place them in the petri dish. 6. Once time has been called, count how many dots you have picked up. Place your data in the table.

4. Color of Dots
Number Picked Up
white
pink
7. Which color was easier to pick up?_________________________________ 8. Why do you think that color was easier? ___________________________________ 9. If you were a dot and did not want to be eaten by the tweezer monster, which color would you want to be?________________.

5. Charles Darwin (1809-1882) Studied biology
In 1831 at age 22, he accepted a job on the HMS Beagle as a scientist
The HMS Beagle docked at the Galapagos Islands off the coast of South America

6. Charles Darwin ( )
Based on fossil evidence, Darwin knew plants and animals change over time
Believed organisms had changed slowly over time and would keep changing
The environment and adaptability of the organisms controlled the changed.

7. What he saw in the Galapagos…

8. What he saw in the Galapagos…
Each island had similar animals with slightly different traits
Long or short necked tortoises depending on the plant height

9. What he saw in the Galapagos…
Finches had many different beak sizes and shapes depending on diet

10. Natural Selection
Darwin’s theory that organisms changed over time based on traits that helped them survive
Survival of the fittest

11. Natural Selection
Organisms with traits that help them survive grow and reproduce passing on those traits to their offspring
Organisms with traits that don’t help them survive are usually eaten or die and don’t pass on their traits

12. Natural Selection
Factors that can affect the process of natural selection
Overproduction of offspring in a species
Competition among organisms of same species
Genetic variations within a population

13. Peppered Moths In England there is a species of peppered moth
They come in two color variations
Light
dark
The trees they lived on had a light bark color
During the industrial revolution, factories were built that produced soot
The soot stained the tree bark black

14. Peppered Moths light dark
Use the moth and bark pictures on your desk to answer.
Which moths were better adapted to the trees before pollution?
Which moths were adapted to the trees after the pollution?
light
dark

15. Elephant Example
Let’s say a group of elephants had mostly short trunks
But a few of the elephants in the group had slightly longer trunks than others
When food and water became scarce, the elephants with longer trunks could reach higher for food and deeper into holes for water

16. Elephant Example
Elephants with shorter trunks would die of thirst and starvation
Elephants with longer trunks would survive and reproduce passing on their longer trunks
Over time, the group would consist mostly of long trunked elephants

18. Elephant Example
Put the elephant cards in the right order

19. Which Beak is Best Lab
When Charles Darwin explored the Galapagos Islands, he discovered 31 different species of ground finches with many different beak sizes and shapes. He theorized that that over time, different groups of finches adapted to their food source by changing their beak shapes. Each beak shape could be matched to the type of food the bird ate.

20. Which Beak is Best Lab
Materials spoon tray with sand tweezers pieces of string eye dropper styrofoam fish beaker of water graduated cylinder of water Procedure Look at the shapes of the bird beaks in the chart. Under each bird’s picture, give at least two things you think it might eat based on the shape of it’s beak.

21. Which Beak is Best Lab

22. Which Beak is Best Lab
On each table there is a spoon, tweezers and an eyedropper. These items are your beaks. There is also a beach filled with worms, a pond filled with fish and a flower with liquid nectar. Using your beaks, decide which beak is best suited to catch and eat each type of food.

23. Which Beak is Best Lab