Population Genetics

Different types of variation in a population
Heritable variation: Understanding why only natural selection can act on this type of variation.
Genetic Drift and Bottleneck Effect: Explanation of these concepts.
Evolutionary Forces: Understanding how each can influence a population's allele frequencies.

Population Variation: Refers to the distribution of phenotypes within a population.
Heritability: The extent to which phenotype variation can be attributed to genetic differences among individuals.
- Selection acts on phenotypes, not genotypes.

Definition: Refers to the diversity of genotypes and alleles within a population.
Inbreeding Depression: Increased occurrence of harmful alleles due to mating between related individuals.
Selection Pressure: The driving force that influences the survival and reproduction of individuals based on traits (e.g., camouflage, size, speed).
Genetic Drift: The random loss of alleles within a population, affecting genetic diversity.

Genetic Drift: More significant impact in small populations; less diversity.
Bottleneck Effect: Occurs when a natural disaster drastically reduces population size, leading to a significant reduction of alleles.
Founder Event: A new population is established by a small number of individuals; alleles in the new population may be reduced compared to the original population.

Gene Flow: Involves the movement of alleles into and out of a population, influencing genetic diversity.
Mutation: Introduces changes in organisms' DNA, serving as a source of new genes.
Nonrandom Mating: Mating choice driven by individual preferences.
- Assortative Mating: Preference to mate with similar phenotypic partners.
Environmental Variation: The environment shapes characteristics of populations (e.g., temperature-dependent sex determination in sea turtles).
Geographical Variation: Differences in populations along a species' distribution, such as size differences in animals depending on the geographical location.