1. Evolution Joke

2. Evolution Jean-Baptiste Lamarck was the first to propose evolution
He believed that the mechanism for evolution was the inheritance of acquired traits
E.g. A Body Builder would have children born with larger muscles

3. Darwin and Evolution

4. Darwin & Evolution
1. Different species of an organism are descendants from an ancestral species.
In other words, species evolve over time.
Known as descent with modification.
2. Evolution occurs by natural selection.

5. Lamarck Vs. Darwin

6. Point 1: Descent With Modification (a.k.a. Evolution)
Occurs when a species of an organism accumulates modifications (i.e. mutations) which help it adapt to the environment
Must affect an entire population’s gene pool in order to be considered evolution.

7. Point 2: Natural Selection
Individuals with characteristics well suited to the environment leave more offspring on average than those less adapted to the same environment.
Based on three observations:
The Struggle for Existence
Natural variations among members of a species
Environmental influence on evolution

8. A. The Struggle For Existence
Species tend to produce more offspring than can survive.
Therefore individuals will compete with one another for limited resources
E.g. Frog Eggs

9. Demonstration

10. B. Natural Variation
Species are inherently different from one another. The organism best adapted to a particular environment has the best opportunity to survive and reproduce.
This is referred to as fitness level.

11. Who has the selective reproductive advantage?

12. Which is More “Fit” Environment A: Hot climate
Environment B: Cold climate

13. Test Your Knowledge: Which is More “Fit”
Environment A: Consists of many predators adapted to poisonous prey.
Environment B: A marsh
Golden poisonous frog

14. Survival of the Fittest: Asian Carp Case Study

15. Survival of the Fittest: Asian Carp Case Study

16. Asian Carp Adaptations
Feed on algae and plankton (food chain impact)
Reproduce very quickly
Can consume 1/5 of their weight per day
Can grow over 100 pounds over their lifetime

17. C. Environment
The environment determines which trait will be advantageous or harmful
In this way the environment exerts a selective pressure on a population
Case and point: Peppered Moth

18. Environment: Peppered Moth Case Study (Read Aloud)
Before Industrial Evolution:
Original peppered moth was light coloured
They camouflaged with the light coloured trees and lichens.
During Industrial Evolution:
Black soot covered trees and lichens died.
Moths that were dark coloured were harder to find (hid from predators) and thus better adapted to the environment.

19. Artificial Selection
The process in which humans select the traits and breed organisms together to produce a desired result.
E.g. Food Crops that produce better yield

20. Homework/In-class work
Read page 310 and summarize the consequences of artificial selection
Answer #1-5, 7, 13 (page 311)