SURVIVAL OF THE FITTEST Natural Selection SURVIVAL OF THE FITTEST

Mutation and Recombination Non-random Random  Natural Selection  Genetic Drift Gene Flow Mutation and Recombination

NATURAL SELECTION- a process by which individuals have inherited beneficial adaptations and show differential reproductive success.

Natural Selection works on populations, NOT individuals!!!

Natural Selection- Survival of the fittest Based on 4 conditions: Variation – populations must exhibit phenotypic variability. Differences must exist between individuals. Some variations are favorable = adaptations Some variations are more favorable Some variations are less favorable.

Thought questions 1 and 2

Based on 4 conditions (Continued) Overproduction- More offspring are born than can survive

Based on 4 conditions (Continued) Heritability – parents must be able to pass traits to offspring

Thought question #3

Based on 4 conditions (Continued) Fitness –Organism’s ability to survive and reproduce relative to other organisms in a given environment. Differential reproductive success- some organisms reproduce better than others

Thought Question #4 & #5

How it works: Favorable traits are “selected for” Individuals with favorable traits are more likely to survive and reproduce Unfavorable traits are “selected against” Individuals with unfavorable traits are more likely to die off ex. Starve or be eaten by predators) and therefore will not reproduce.

Removal of unfavorable traits (alleles) and an increase in favorable traits (alleles) cause change in population over time = Evolution

Thought Question #6