Ecology
The study of interactions among and between organisms in their abiotic environment.
Abiotic Factors
The non-living, physical factors that influence the organisms and ecosystem — such as temperature, sunlight, pH, salinity, and precipitation.
Biotic Factors
The interactions between the organisms—such as predation, herbivory, parasitism, mutualism, disease, and competition.
Species
A group of organisms that share common characteristics and that interbreed to produce fertile offspring
Habitat
A habitat is the environment in which a species normally lives
Niche
A niche describes the particular set of abiotic and biotic conditions and resources to which an organism or population responds
Fundamental niche
Describes the full range of conditions and resources in which a species could survive and reproduce
Realized niche
Describes the actual conditions and resources in which a species exists due to biotic interactions
Resource Partitioning
The fundamental niches of two species overlap and through competition develop a narrower realized niche
Mutualism
Symbiotic relationship in which both partners benefit
Commensalism
A symbiotic relationship in which one organism benefits and the other one is neither harmed nor helped
Parasitism
Symbiotic relationship in which one species is benefited and the other is adversely affected
Predation
The consumption of one species (the prey) by another (the predator).​
Herbivory
The consumption of a plant species by an animal
Competition
This is the interaction between organisms that are trying to attain the same resources. This might be food but it could also be for mates, territory, nesting sites, etc.
Decomposer
Feeds on dead and decaying material, thus recycling the nutrients.
J-Shaped Curve
A population growth curve showing exponential growth with no carrying capacity reached.
S-Shaped Curve
A population growth curve showing exponential growth followed by slowed growth until carrying capacity is reached.
Carrying Capacity
The maximum population size that a given area can support sustainably.
Limiting Factors
Biotic or abiotic factors which lead to a limit in the population growth.
Density-dependent Limiting Factors
Limiting factors related to how densely packed a population is, e.g. competition
Density-independent Limiting Factors
Limiting factors unrelated to population density such as natural disasters and weather change.
Symbiosis
individuals living on or in individuals of another species where one or both species use the others resources. Includes mutualism, commensalism and parasitism.