Jan 24
Natural selection? Survival of the fittest
Four requirements (postulates)
1. Individuals vary
2. This variation is heritable (at least partially) EX: Height
3. Not all individuals survive & reproduce equally
- Survive- long enough
4. The difference in survival and reproduction are linked to the variation and
postulate #1
Adaptation: a trait that increases the chance that a given individual will survive and
reproduce, increasing the frequency of the trait in the next generation
Positive selection: selection for a beneficial change (rare)
Purifying selection: selection against deleterious changes (common)
What are the mechanisms of evolutionary change?
●Nature Selection Mutation
●Gene flow
