APES - Unit 5 - Population & Community & Conserving Biodiveristy

specialist species

Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food.

generalist species

species with a broad ecological niche

precautionary principle

a principle based on the belief that action should be taken against a plausible environmental hazard

indicator species

Species that serve as early warnings that a community or ecosystem is being degraded.

endemic species

species that are native to and found only within a limited area

keystone species

A species that influences the survival of many other species in an ecosystem

pioneer species

First species to populate an area during primary succession

invasive species

plants and animals that have migrated to places where they are not native

habitat

the natural home or environment of an animal, plant, or other organism.

range of tolerance

the limits to the abiotic conditions that a species can tolerate

Niche

An organism's particular role in an ecosystem, or how it makes its living.

competitive exclusion principle

Ecological rule that states that no two species can occupy the same exact niche in the same habitat at the same time

resource partitioning

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

competition

the struggle between organisms to survive in a habitat with limited resources

prediation

a relation between animals in which one organism captures and feeds on others.

Parasitism

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

Commensalism

A relationship between two organisms in which one organism benefits and the other is unaffected

Mutualism

A relationship between two species in which both species benefit

Symbiosis

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

community structure

the set of characteristics that shape communities

ecological succession

gradual change in living communities that follows a disturbance

primary succession

An ecological succession that begins in an area where no biotic community previously existed

secondary succession

Succession following a disturbance that destroys a community without destroying the soil

climax forest

the oldest forests once considered by ecologists to have ended succession (now recognized that natural disturbances can reset to an earlier stage)

Population

A group of individuals that belong to the same species and live in the same area

Population range

the geographical area in which a specific species can be found

population spacing

how the organisms are arranged in a given area

clumped dispersion

The most common pattern of dispersion; individuals aggregated in patches.

uniform dispersion pattern

a pattern in which the individuals of a population are evenly distributed over an area

random dispersal

individuals in a population are spaced in an unpredictable way without a pattern. ex. dandelions that grow from windblown seeds might be randomly dispersed.

population size

the total number of individuals within a defined area at a given time

age structure

Percentage of the population (or number of people of each sex) at each age level in a population.

survivorship curve

a diagram showing the number of surviving members over time from a measured set of births

survivorship type 1

late loss, heavy parental care

survivorship type 2

relatively constant survivorship throughout life

ex. birds

survivorship type 3

Early loss; produce lots of offspring at once and many die right away

reproductive strategies

Behaviors or behavioral complexes that have been favored by natural selection to increase individual reproductive success. The behaviors need not be deliberate, and they often vary considerably between males and females.

K-selected species

Species that produce a few, offspring but invest a great deal of time and energy to ensure that most of those offspring reach reproductive age.

r-selected species

Species that reproduce early in their life span and produce large numbers of usually small and short-lived offspring in a short period.

Population growth formula

births - deaths + immigration - emigration

Exponential growth rate

Continuous increase in a population at a rate that is proportional to the number of individuals at a given time.

non-native species

A species that is not naturally found in an area. These organisms come from a different country or part of the world.

Logistic growth rate

S-shaped, slows or stops at the population's carrying capacity

carrying capacity

Largest number of individuals of a population that a environment can support

conserving biodiversity

Conservation efforts focus on protecting entire ecosystems as well as single species, to insure that natural habitats and the interactions of many different species are preserved.

Extinction rates

Extinction rates right now are unprecedented, about 1000 times higher than the fossil record. Projected rates are another 10 times higher. There simply isn't room on the planet for so many humans living the way we do to maintain all the other species

endangered species

A species whose numbers are so small that the species is at risk of extinction

threatened species

A species that could become endangered in the near future

Regionally Extinct

a species is no longer found in part of its former range but still lives elsewhere.

functionally extinct

To the point at which species can no longer play a functional role in the ecosystem

HIPPCO

Habitat destruction, Invasive Species, Population growth, Pollution, Climate Change, Overexploitations

*habitat destruction is #1 threat to animals

Bioaccumulation

The accumulation of a substance, such as a toxic chemical, in various tissues of a living organism.

Overexploitation

overuse of species with economic value--a factor in species extinction

Convention on International Trade in Endangered Species

International agreement between governments whose aim is to ensure that international trade in specimens of wild animals & plants does NOT threaten the survival of the species

Convention on Biological Diversity

An international treaty to help protect biodiversity

Endangered Species Act (ESA)

Protects species that are considered to be threatened or endangered. Includes migratory birds and their habitats.

Wildlife sanctuaries

Preserved land for living things