Exploration 1: Genetic Variation in Populations

1. Natural Selection: The process by which organisms better adapted to their environment tend to

survive and produce more offspring.

2. Gene Pool: The total set of different genes present in a population.

3. Crossing Over: The exchange of genetic material between homologous chromosomes during

meiosis, leading to genetic diversity.

4. Recombination: The process by which genetic material is broken and joined to other genetic

material, contributing to genetic variation.

5. Allele: Different forms of a gene that arise by mutation and are found at the same place on a

chromosome.

6. Allele Frequency: The relative frequency of an allele at a particular locus in a population,

expressed as a fraction or percentage.

7. Genotype Frequency: The proportion of different genotypes in a population.

8. Hardy-Weinberg Equation/Equilibrium: A principle stating that the genetic variation in a population

will remain constant in the absence of disturbing factors.

Exploration 2: Selection on Populations

1. Normal Distribution: A bell-shaped distribution of traits in a population, where most individuals

have average traits and fewer have extreme traits.

2. Microevolution: Small-scale evolutionary changes within a species or population, typically over a

short period of time.

3. Stabilizing Selection: A type of natural selection that favors average individuals in a population.

4. Directional Selection: A type of natural selection that favors one extreme phenotype over the

mean or other extreme.

5. Disruptive Selection: A type of natural selection that favors extreme values of a trait over

intermediate values.

Exploration 4: Effects of Gene Flow

1. Gene Flow: The transfer of genetic variation from one population to another.

2. Genetic Drift: Random changes in allele frequencies in a population, especially in small

populations.

3. Bottleneck Effect: A sharp reduction in the size of a population due to environmental events or

human activities, resulting in a loss of genetic diversity.

4. Founder Effect: The reduced genetic diversity that results when a population is descended from a

small number of colonizing ancestors.

5. Sexual Selection: A mode of natural selection where typically members of one gender choose

mates of the other gender with specific traits.

6. Intrasexual Selection: Competition among members of the same sex (usually males) for mating

opportunities.

7. Intersexual Selection: Selection whereby individuals of one sex (usually females) are choosy in

selecting their mates from individuals of the other sex.

Exploration 5: Mechanisms of Speciation

1. Speciation: The formation of new and distinct species in the course of evolution.

2. Reproductive Isolation: A collection of mechanisms, behaviors, and physiological processes that

prevent the members of two different species that cross or mate from producing offspring.

3. Geographic Isolation: When physical barriers divide a population into two or more groups, leading

to speciation.

4. Behavioral Isolation: Differences in mating behaviors that prevent different species from

interbreeding.

5. Temporal Isolation: When two species breed at different times of day, season, or years,

preventing mating.

6. Adaptive Radiation: The diversification of a group of organisms into forms filling different

ecological niches.

Lesson 3

Exploration 1: Evolution of Behavior

Stimulus: A change in the environment that can elicit a response from an organism.

Receptor: A specialized cell or group of nerve endings that responds to sensory stimuli.

Response: A reaction by an organism to a stimulus.

Innate behavior: A behavior that is developmentally fixed and under strong genetic control.

Instinctive behavior: A complex behavior that is rigidly patterned throughout a species and is

unlearned.

Homeostasis: The maintenance of stable internal conditions in an organism.

Migration: The regular, long-distance change in location by animals.

Benefit: An advantage or profit gained from something.

Cost: The effort, loss, or sacrifice necessary to achieve or obtain something.

Swarm: A large group of insects or other small organisms, especially when in motion.

Murmuration: A phenomenon when starlings fly in swooping, intricately coordinated patterns.

Opportunity cost: The loss of potential gain from other alternatives when one alternative is chosen.

Protecting territory: The defense of a defined area against other individuals, typically of the same

species.

Protecting mates: Behaviors aimed at defending a reproductive partner from rivals.

Survivorship: The percentage of a cohort surviving to a certain age.

Hunting in groups: The cooperative hunting strategy used by some animals.

Exploration 2: Social Interactions

Flocking: A behavior exhibited when a group of birds or other animals move together in a

coordinated manner.

Schooling: The behavior of fish swimming together in the same direction in a coordinated manner.

Communication: The transfer of information from one organism to another.

Mate selection: The process by which individuals choose their reproductive partners.

Defense: Behaviors used to protect oneself or one's group from threats.

Cooperation: The process where groups of organisms work or act together for common or mutual

benefits.

Reciprocity: The exchange of resources, goods, and services among individuals of a group.

Altruism: Behaviors that benefit other individuals at a cost to oneself.

Eusocial: The highest level of social organization, where individuals of the same species cooperate

in caring for the young, and there is a division of labor into reproductive and non-reproductive

groups.

Exploration 3: Learned Behaviors

Learning: A relatively permanent change in behavior due to experience.

Animal cognition: The study of the mental capacities of non-human animals.

Intelligence: The ability to acquire and apply knowledge and skills.

Cognitive abilities: The mental skills that include learning, thinking, reasoning, remembering,

problem-solving, decision-making, and attention.

Cultural behavior: Behaviors that are learned and transmitted through social interactions within a

community.