1. Warmup:
Open your lab book to the Kerosene Karl activity we did yesterday in class.
Make a graph (in your lab book--after the questions is fine) with the percent (%) of each allele on the Y-axis and the generation number on the X-axis.
You should have 2 lines
One for C allele
One for c allele
Allele % 1 2 3 4 5 6 7 8 9 10
Generation

2. Natural Selection

3. Darwin Publishes 1836 – returns from Beagle voyage
1858 – receives short essay from Alfred Wallace
1859 – publishes ‘On the Origin of Species’
Proposed Natural Selection is how evolution occurs
Evolution has worked over millions of years and continues today

4. Heritable Variation Variation exists in nature (some examples)
Fruit size
Milk production
Speed
Height
Coloration

5. Artificial Selection
Humans selecting and breeding organisms for useful traits
Traits are part of the natural variation among the organism

6. Warmup Revisit Kerosene Karl
Evolution is the change in the allele frequency of a population. Did evolution occur in the caterpillar population in Kerosene Karl?
2. Identify each of the following points from Kerosene Karl:
Population has variations.
Some variations are favorable
More offspring are produced than survive
Those that survive have favorable traits.
A population will change over time.

7. Natural Selection
Process that describes how evolution takes place in nature
Struggle for Existence
Survival of the Fittest
Descent with Modification

8. 1. Struggle for Existence
Malthus
High birth rates, shortage of basic needs = competition for resources
Members of species compete for food, living space, other necessities
Predators that are faster get more food
Prey that are faster or camouflaged avoid being caught

9. 2. Survival of the Fittest
Fitness = Ability of an individual to survive AND reproduce
how well suited an organism is to its environment
Adaptation = inherited characteristic that increases an organisms chance of survival

10. 2. Survival of the Fittest
Well suited individuals survive and reproduce more successfully (high fitness)
Individuals with traits not suited to environment die or have few offspring (low fitness)
Evolution clip

11. How is each of these traits adaptive in nature??
Orangutan’s long arms
Harmless flies that mimic the sound of an angry bee/wasp
Butterflies of one species that resemble other poisonous butterflies
An insect that looks like a leaf or a stick- camouflage
An opossum playing dead
Behavioral vs. physical adaptations 11

12. 2. Survival of the Fittest
Only certain individuals produce offspring for next generation
Over time, natural selection changes the inherited characteristics of a population

13. SELECTION
Individuals without advantageous traits die before reproducing.
Individuals with advantageous traits survive to reproduce.
Again, make note the labeling of the axes
Frequency
die without reproducing
These individuals
These individuals
survive to reproduce
Characteristic 13

14. Populations change, not individuals
The “average” characteristic or other measure of the population changes over generations
average, 1st gen.
average, 2nd gen.
average, 3rd gen.
average, 50th gen.
Frequency
die without reproducing
These individuals
die without reproducing
These individuals
These individuals
survive to reproduce
Characteristic

15. 3. Descent with Modification
Each living species has descended – with changes – from other species over time
All living organisms are related to one another
Natural Selection produces organisms
With different structures
Occupy different habitats

16. HOMEWORK Read section 15-3 in your textbook
Complete WS 15-3 up to “Evidence for Evolution” (#1-16)