Biodiversity

type I survivorship curve

type I survivorship curve

Survivorship curve exhibited by species with a high survival rate of their young and most individuals dying at old age

type II survivorship curve

Survivorship curve exhibited by species in which individuals die at a constant rate from hunting, disease, etc.

type III survivorship curve

Survivorship curve exhibited by species in which most individuals die when young

r selection

Strategy used by a population below its carrying capacity (population can still grow exponentially)

K selection

Strategy used by a population at or almost at its carrying capacity

biotic potential

the maximum reproductive capacity of a population under ideal conditions

limiting factor

An environmental factor that prevents a population from increasing

intraspecific competition

Competition between members of the same species

interspecific competition

Competition between members of different species

predation

An interaction in which one organism kills another for food.

Allee effect

A biological phenomenon in which undercrowding (low density), not competition, limits population growth

minimum viable population size

the smallest number of individuals that ensures the population can persist for a determined amount of time

density-dependent factor

Factors have varying impacts according to population size, different species populations in the same ecosystem will be affected differently (also called biotic limiting factors)

density-independent factor

Factors that are not influenced by a species population size, all species populations in the same ecosystem will be similarly affected, regardless of population size (also called abiotic limiting factors)

niche

An organism's particular role in an ecosystem, including all of the interactions with biotic and abiotic factors

resource partitioning

The division of resources to reduce interspecific competition for limited resources in an ecosystem (species occupy slightly different niches)

mimicry

Ability of an animal to look like another more harmful animal

symbiosis

A close relationship between two species that benefits at least one of the species

mutualism

A relationship between two species in which both species benefit

commensalism

A relationship in which one organism benefits and the other is neither helped nor harmed

parasitism

A relationship in which one organism lives on or in a host and harms it

extinct

Any species that no longer exists anywhere on Earth

extirpated

Any species that no longer exists anywhere in Canada

endangered

Any species close to extinction in all, or part, of Canada

threatened

Any species likely to become endangered, if things don’t change

special concern

Any species that is at risk due to low or declining numbers

size

Factor influencing the status of a species: larger animals need more food and more space

range (species and individual)

Factor influencing the status of a species: An animal that is found at only one place is at risk if anything happens to that place

diet

Factor influencing the status of a species: A carnivore is at greater risk because its food may become rare more readily than a herbivore’s food will become rare. Also, a specific diet is riskier than a general diet. Also consider biomagnification.

fecundity

Factor influencing the status of a species: Reproductive rate (birth rate, survival to reproductive age, births per year and births per lifetime are part of this), low rate = more at risk

human interactions

Factor influencing the status of a species: Some animals do well around people and some do not (hunting, killed by cars, reduced range, pollution, etc.)

habitat degradation/loss

Cause of species decline: #1 reason of decline, e.g. deforestation, habitat cleared for livestock

water, soil and air pollution

Cause of species decline: e.g. mercury poisoning, oil spill contamination

overexploitation

Cause of species decline: e.g. pet trade, hunting, overfishing

alien species

Cause of species decline: e.g. Emerald Ash Borer, zebra mussel

disease

Cause of species decline: e.g. Ebola, rabies, canine distemper virus