Natural Selection

Day 121You, too, can be selected naturally!

What is NATURAL SELECTION?

• The process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well adapted individuals do

Variation is random, selection is not

• In our class, we are all female – as in we are human women. We have a lot in common!

• Like…

Variation is random, selection is not

• But we’re not all the same!• Like…

The “Average” Woman

The “Average” Woman, con’t

The “Average” Woman, con’t

The “Average” Woman, con’t

What is GENETIC VARIATION?

• The variety of different types of genes in a species or population

• Why do you think variations occur?

Humans aren’t the only organisms that have genetic variations

Variations, con’t

Variations, con’t

• http://www.khanacademy.org/video/introduction-to-evolution-and-natural-selection?playlist=Biology

ES121

• Take out a sheet of paper. clear everything else off of your desk.

• When you are done you may silently pack up and stand behind your chair.

ES121

1. True or False? Genetic variation occurs only in mammals.

2. True or False? Organisms mutate purposefully to increase chances of survival.

3. What causes genetic variation?4. Give an example of genetic variation.5. Give an example of an environmental change

that might make one genetic variation more successful in a population.