1. 3 Types of Natural Selection

2. 1. Directional Selection a. Favors those w/extreme variations in
traits w/in a population
b. breeding of the greyhound dog
-bred for speed
- selected those who ran the fastest
- Egypt 3BC: used to hunt fastest game (fox, deer)

3. c. Wolves from Minn migrate to N. Canada for food
-thicker coats are more fit
-better chance of passing traits on

4. 2. Stabilizing Selection a. Favors the norm/average traits
b. Siberian Husky bred for working in snow
-medium dog w/ strong leg muscle
-if heavier  sink in snow
-if lighter  cannot pull sleds

5. -small enough to hide from predators
c. Mice survival
-small enough to hide from predators
-large enough to fight rats for food
-medium size best

6. a. Also favors the extreme traits b. Crabs live on shoreline
3. Disruptive Selection
a. Also favors the extreme traits
b. Crabs live on shoreline
-brown  blend in better in water
-lighter  blend in better on land
-medium  more easily spotted &
picked off in predation