AP Bio 8-2 vocab terms

Carrying capacity

The maximum population size that can be supported by the available resources, symbolized as K.

Emigration

The movement of individuals out of a population.

R-selection

The study of how complex interactions between biotic and abiotic factors influence variations in population size.

Cryptic coloration

Camouflage that makes a potential prey difficult to spot against its background.

Competition

A -/- interaction that occurs when individuals of different species compete for a resource that limits the survival and reproduction of both individuals. Competition for resources can also occur between members of the same species; this case is sometimes distinguished as interspecific competition.

Evapotranspiration

The total evaporation of water from an ecosystem, including water transpired by plants and evaporated from a landscape, usually measured in millimeters and estimated for a year.

Competitive exclusion

The concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population.

Community

All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction.

Shannon diversity index

An index of community diversity symbolized by H and represented by the equation H =-(pA In pA + pB In pB + pC In pC+...), where A, B, C... are species, p is the relative abundance of each species, and In is the natural logarithm.

Secondary succession

A type of succession that occurs where an existing community has been cleared by some disturbance that leaves their soil or substrate intact.

Relative abundance

The proportional abundance of different species in a community.

Endoparasites

A parasite that lives within a host.

Biomass

The total mass of organic matter comprising a group of organisms in a particular habitat.

Tropic structure

The different feeding relationships in an ecosystem, which determine the route of energy flow and the pattern of chemical cycling.

Zoonotic pathogen

A disease-causing agent that is transmitted to humans from other animals.

Tropic level

The position an organism occupies in a food chain.

Ecosystem engineer

An organism that influences community structure by causing physical changes in the environment.

Ectoparasites

A parasite that feeds on the external surface of a host.

Resource partitioning

The division of environmental resources by coexisting species such that the niches of each species differs by one or more significant factors from the niches of all coexisting species.

Nonequilibrium model

A model that maintains that communities change constantly after being buffeted by disturbances.