Abiotic factors
Nonliving environmental factors such as temperature, water, sunlight, and soil.
Age structure
The distribution of individuals among age groups in a population.
Biodiversity
The variety of species within an ecosystem.
Biotic factors
Living components of an ecosystem (plants, animals, bacteria).
Boom and bust cycle
Rapid population growth followed by a sudden crash.
Carrying capacity (K)
The maximum population size an environment can support long-term.
Coevolution
Evolution of two species in response to each other.
Commensalism
A symbiotic relationship where one species benefits and the other is unaffected.
Competition
Struggle between organisms for limited resources.
Competitive exclusion
Principle stating that two species cannot occupy the same niche indefinitely.
Density-dependent factors
Factors whose effects increase as population density increases.
Density-independent factors
Factors that affect populations regardless of their density.
Demography
The statistical study of population size, growth, and structure.
Dispersion
The pattern of spacing of individuals in a population.
Ecology
The study of interactions between organisms and their environment.
Equilibrial population
A population that remains relatively stable near carrying capacity.
Exponential population growth
Rapid growth under ideal conditions with unlimited resources.
Fundamental niche
The full range of environmental conditions a species can potentially occupy.
Herbivory
A relationship in which an organism feeds on plants.
Invasive species
A non-native species that spreads rapidly and disrupts ecosystems.
K-selected population
Populations with few offspring and high parental care.
Life table
A chart showing survival and reproduction rates at different ages.
Limiting factors
Environmental factors that restrict population growth.
Logistic population growth
Growth that slows and levels off at carrying capacity.
