Populations & Ecology

Flashcards covering key terms and concepts on populations and ecology.

Population

All of the members of a species that live in a given area during a period of time.

Population Size

The number of individuals in a population, affecting its ability to survive.

Founder Effect

Occurs when a few organisms start a new population, with traits of the founders becoming more common.

Genetic Drift

Random events that change allele frequency in populations, leading to divergence.

Population Density

Number of individuals that live in a given space.

Population Dispersion

The way organisms are arranged in space; can be random, uniform, or clumped.

Immigration

Movement of individuals into an area, often in search of mates or food.

Emigration

Movement of individuals out of an area, often due to food shortages or to establish new territory.

Exponential Growth

Population growth that continues indefinitely at a constant rate.

Logistic Growth

Population growth that slows or stops after exponential growth, reaching carrying capacity.

Limiting Factors

Factors that cause population growth to slow or stop; can be density-dependent or density-independent.

Symbiosis

Close, long-term association between two or more species which can be mutualistic, parasitic, or commensal.

Biogeochemical Cycles

Processes that allow important materials to be transferred between organisms and the environment.

Carrying Capacity (K)

The maximum number of organisms a population can support in a given environment.

Density-Dependent Factors

Limiting factors that slow growth only in high-density populations.

Density-Independent Factors

Limiting factors that affect growth regardless of population density.