1. Darwin’s Reasoning for Natural Selection
Voyage of the Beagle
Darwin’s Reasoning for Natural Selection

2. First Station:
You will see 3 examples of living organisms. Write what you observe on each slide in the space provided on your handout, then write what pattern you observe and why you think you see this pattern…

3. Observation 1: SLIDE #1
This is a sunflower with a close-up of the seeds on one flower. Approximately, how many seeds do you see on the one flower?

4. Observation 1: SLIDE #2
Drosophila melanogaster are fruit flies. Each female can lay 400 eggs, which hatch after 12 hours.

5. Observation 1: SLIDE #3
Bacteria, like E. coli, can reproduce by binary fission at a fast rate.

6. Observation 2:
We’re watching you. Stop goofing off! ;)

7. Observation 2:
Here is a litter of kittens; what variability exists?

8. Observation 2:
Their father Their mother

9. Observation 2:
These zebra finches are siblings.

10. Observation 2:
The father The mother

11. Observation 3:
Here, a herd of zebras is running. Describe how they look as a group. (Hint: notice the effect of the stripes when the zebras are so close together…)

12. Observation 3:
When the lion hunts the zebra, she isolates one to chase. She has trouble singling out one zebra from a running herd, due to the stripes.

13. Observation 3:
Special zebra mutations:

14. Observation 3:

15. Observation 3:

16. Observation 4:
This is a type of insect called a grub. Individuals of this species come in two sizes, big and small. Each individual can make 2 babies each breeding cycle. Watch what happens to them in two different environments.

17. Observation 4: FIRST SCENARIO

18. Observation 4: FIRST SCENARIO

19. Observation 4: FIRST SCENARIO

20. Observation 4: FIRST SCENARIO

21. Observation 4: FIRST SCENARIO
Do you see the trend that has formed? What will happen to this population of grubs?

22. Observation 4: SECOND SCENARIO

23. Observation 4: SECOND SCENARIO

24. Observation 4: SECOND SCENARIO

25. Observation 4: SECOND SCENARIO

26. Observation 4: SECOND SCENARIO
Do you see the trend that has formed? What will happen to this population of grubs?