Questions and Answers
What is immigration?
What is emigration?
What is gene flow?
Process of a gene moving from one population to another.
What is genetic drift?
Signup and view all the answers
What is sexual selection?
Signup and view all the answers
What is stabilizing selection?
Signup and view all the answers
What is disruptive selection?
Signup and view all the answers
What is directional selection?
Signup and view all the answers
List five conditions that can disrupt genetic equilibrium.
Signup and view all the answers
Explain the role of mutations in evolution.
Signup and view all the answers
Contrast gene flow with genetic drift.
Signup and view all the answers
Explain why genetic drift is more significant in smaller populations.
Signup and view all the answers
Contrast stabilizing selection, disruptive selection, and directional selection.
Signup and view all the answers
Study Notes
Population Dynamics
- Immigration: Refers to individuals moving into a population, which can increase population size.
- Emigration: Involves the movement of individuals out of a population, resulting in a decrease in population size.
Genetic Processes
- Gene Flow: The transfer of genetic material between populations, which can introduce new genes or alleles to a gene pool.
- Genetic Drift: A random change in allele frequencies within a population, particularly significant in small populations due to chance events.
Selection Types
- Sexual Selection: A process where certain traits in males are favored for selection by females, influencing mating success.
- Stabilizing Selection: Favors average traits in individuals, leading to higher fitness for those with traits near the mean.
- Disruptive Selection: A form of natural selection that favors individuals at both extremes of a trait distribution, potentially leading to speciation.
- Directional Selection: Occurs when one extreme of a trait is favored, shifting the population traits towards that extreme.
Evolutionary Mechanisms
-
Disruption of Genetic Equilibrium: Five conditions that can alter allele frequencies, promoting evolution:
- Changes in allele frequencies due to mutations.
- A constant population size.
- Presence of a large population minimizes fluctuations.
- Random mating conditions.
- Absence of natural selection.
Role of Mutations
- Mutations generate genetic variation that serves as the substrate for natural selection, influencing evolutionary change.
Comparisons and Contrasts
-
Gene Flow vs. Genetic Drift:
- Gene flow introduces new genetic material, whereas genetic drift leads to accumulation of changes in a population over time.
-
Stabilizing vs. Disruptive vs. Directional Selection:
- Directional Selection favors one extreme trait, shifting the mean trait value.
- Disruptive Selection supports extreme traits over intermediates, increasing variance and facilitating speciation.
- Stabilizing Selection promotes intermediate traits, reducing variance and genetic diversity.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore key concepts in Biology Chapter 16.2 with this set of flashcards. Each card presents a vital term and its definition, focusing on immigration, emigration, gene flow, and genetic drift. Perfect for students looking to deepen their understanding of population dynamics.