GEE 001 - Species Interactions, Ecological Succession, and Population Control

Interspecific Competition

When two or more species in an ecosystem compete for the same limited resources, like food, space, or shelter.

Resource Partitioning

When species that compete for similar resources evolve to use them at different times, places, or in different ways, so they can share resources without direct conflict.

Predation

An interaction where one species (the predator) hunts, kills, and feeds on another species (the prey).

Mimicry

When a harmless species evolves to look like a dangerous or bad-tasting species to avoid being eaten.

Camouflage

A defense strategy where a prey species blends into its surroundings so predators can't easily see it.

Coevolution

When two species interact closely over a long time, causing each species to evolve in response to changes in the other.

Parasitism

An interaction where one organism (the parasite) lives on or inside another organism (the host), feeding off it and usually weakening but not killing it.

Mutualism

An interaction where two species live closely together and both benefit from the relationship.

Commensalism

An interaction where one species benefits while the other species is neither helped nor harmed.

Ecological Succession

The gradual, natural process of change in the species living in an area over time.

Primary Succession

The slow establishment of living communities in a lifeless area with no soil or sediment, such as bare rock; takes hundreds to thousands of years.

Secondary Succession

The re-establishment of a community in an area where soil or sediment already exists, usually after a disturbance like a fire or clearing.

Population

A group of individuals of the same species living together in the same area and able to interbreed.

Range of Tolerance

The span of environmental conditions (like temperature) within which a population can survive and function.

Limiting Factor

A physical or chemical factor that restricts the growth, abundance, or distribution of a population.

Population Density

The number of individuals of a population living within a specific area.

Density-Dependent Factor

A factor that has a greater effect as a population's density increases, such as disease spreading more easily in crowded populations.

Density-Independent Factor

A factor that affects a population's size regardless of how dense it is, such as weather or natural disasters.

Exponential Growth (J-Curve)

Population growth that starts slow then increases rapidly, forming a J-shaped curve, occurring when resources are unlimited.

Environmental Resistance

All the limiting factors that together restrict the growth of a population.

Carrying Capacity

The maximum population size that an environment can support indefinitely without being damaged.

Logistic Growth (S-Curve)

Population growth that slows as it approaches carrying capacity, forming an S-shaped curve.

Population Crash (Dieback)

A sharp decline in population size that happens when a population exceeds its environment's carrying capacity.

r-Selected Species

Species that reproduce quickly, produce many small offspring, and provide little parental care, relying on numbers for survival.

K-Selected Species

Species that reproduce later in life, have fewer, larger offspring, and provide significant parental care.

Survivorship Curve

A graph showing the likelihood of survival at each age for members of a population.