This document provides instructions and content for a science journal assignment on natural selection. It includes: - Definitions of key terms like organism, population, and natural selection. - An example of natural selection in peppered moths, explaining how light-colored moths had an advantage on light-colored trees but dark moths had an advantage when pollution made the trees dark. - Processing questions to illustrate the steps of natural selection using moths or other examples. - Reminders to use already filled notes and that there will be a retest during lunch for those who failed a previous test.

1. Assign Yourself: Update Science
Journal by Tomorrow
• Do Now:
• Unit 2 Review

2. For your journal, you need to have:
• All Unit 2 Notes cut and pasted in
• ***HUGE TIP: If you have the notes already
filled in, use those or it will be MORE work
over the weekend!!!***

3. Natural Selection

4. What is an organism?
• Any living thing (animal, plant, bacteria, etc.)

5. Processing Piece:
• Write “organism” and draw a picture to show
what it means.

6. What is a population?
• A group of organisms

7. Processing Piece:
• Write “population” and draw a picture to
show what it means.

8. What is natural selection?
• A process that causes populations to change
over time.

9. Processing Piece:
• Write “natural selection” and draw a picture
to show what it means.
• Next to it, write “change over time.”

10. What 2 things do you need in order for
there to be natural selection?
1. There must be variation in the population.
– “Variation” = different traits
– Examples: giraffes that are different heights

11. What 2 things do you need in order for
there to be natural selection?
2. Some traits must be more advantageous than
others.
– “Advantageous” = gives the organism an advantage;
helps it survive
– Example: taller giraffes can reach higher leaves

12. How does natural selection work?
1. There is variation and an advantageous trait in a
population.
2. More individuals with that trait survive.
3. They reproduce more, creating offspring (kids) that
also have the trait.
Over multiple generations…
4. That trait becomes more common in the
population.

13. Example: Moths on trees
Peppered moths can be light or dark. This is an
example of variation (different traits).

14. Example: Moths on trees
When trees had white bark, the ___________ moths
survived better, because it was harder for predators
like birds to see them.
Tree trunk
Light moth
Dark moth

15. Example: Moths on trees
When trees had white bark, the light moths
survived better, because it was harder for predators
like birds to see them.
Tree trunk
Light moth
Dark moth

16. Example: Moths on trees
Since light moths survived better, they had more
offspring. Since they had more offspring, most of the
population was light colored.
Population
Most moths are
light.
Light moth
Dark moth

17. Example: Moths on trees
Due to pollution, the tree bark became dark. When
this happened, the _____________ moths survived
better.
Tree trunk
Light moth
Dark moth

18. Example: Moths on trees
Due to pollution, the tree bark became dark. When
this happened, the dark moths survived better.
Tree trunk
Light moth
Dark moth

19. Example: Moths on trees
Since dark moths survived better, they had more
offspring. Since they had more offspring, over time,
most of the population became dark colored.
Population
Most moths are
dark.
Light moth
Dark moth

20. Processing Piece:
• Illustrate each step of natural selection.
1. There is variation and an advantageous trait.
2. More individuals with that trait survive.
3. They reproduce more.
Over several generations…
4. That trait becomes common.
Use the moth example, or any other example you
want.

22. Announcement!
• Retest during lunch.
• If you failed, you MUST come and retest.

23. Exit Ticket
1. Does natural selection change individuals or
populations over time?
2. If trees are dark colored, which will have
more offspring: light moths or dark moths?
3. Did you do as well on the test as you
thought you did?
4. Why do you think you got the grade you
got?

24. Assign Yourself: Finish Quackers
Questions
• Do Now:
• Review of Unit 2, numbers 1-6

25. Exit Ticket:
• 1. Why were the dark quackers more fit
(ability to survive more)?
• 2. During natural selection, what changes over
time: individuals or populations?
• 3. What was the variation of traits between
the quackers?
• 4. Did the population change instantly or over
multiple generations?

26. Thirsty for T-STEM Thursday!!! An
Anthropologist!
• What do they do?

27. Keyfacts:
• Hours: 50-60
• PhD Needed
• TRAVEL A LOT to different countries

28. Lifestyle

29. Assign Yourself: IA2 Review
• Do Now:
• Natural Selection Review 1-4

30. Let’s grade our notebooks
• Please take your notebook out. You have 30
seconds to have it on your desk and ready to
grade.