APES Withgott and Laposata Chapter 4 Species Interactions and Community Ecology

Competition

A common demand by two or more organisms upon a limited supply of a resource; for example, food, water, light, space, mates, nesting sites. It may be intraspecific or interspecific.

Fundamental Niche

The full potential range of the physical, chemical, and biological factors a species can use if there is no competition from other species.

Realized Niche

The part of fundamental niche that an organism occupies as a result of limiting factors present in its habitat.

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.

Predation

An interaction in which one organism kills another for food.

Parasitism

A relationship between two organisms of different species where one benefits and the other is harmed.

Herbivory

An interaction in which an organism eats parts of a plant or alga.

Mutualism

A relationship between two or more organisms of different species where all benefit from the association.

Symbiosis

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

Amensalism

A symbiotic relationship between organisms in which one species is harmed or inhibited and the other species is unaffected

Commensalism

A relationship between two organisms of different species where one benefits and the other is neither harmed nor benefited

Trophic Level

A position in a food chain or Ecological Pyramid occupied by a group of organisms with similar feeding mode.

Food Web

A community of organisms where there are several interrelated food chains.

Keystone Species

a species whose impact on its community or ecosystem are much larger and more influential than would be expected from mere abundance

Resistance

The degree to which a community resists change and remains stable despite disturbances in ecosystem.

Resilience

Ability of a community to restore itself to original condition after being exposed to an outside disturbance that is not too drastic.

Sucession

When older communities are replaced with new ones. Competition among species favors those who best make use of available water, light and nutrients.

Primary Sucession

The development of communities in a lifeless area not previously inhabited by life or those in which the soil profile is totally destroyed (lava flow); begins with lichen action.

Secondary Sucession

An existing community is destroyed by a natural disaster and the original community regrows over time, soil profile not destroyed.

Pioneer Species

First species to populate an area during primary succession

Invasive Species

An introduced species that spreads widely and rapidly becomes dominate in a community, interfering with the community's normal functioning.

Ecological Restoration

Deliberate alteration of a degraded habitat or ecosystem to restore as much of its ecological structure and function as possible.

Restoration Ecology

Applying ecological principles in an effort to return ecosystems that have been disturbed by human activity to a condition as similar as possible to their natural state.

Biome

A group of ecosystems that share similar climates and typical organisms.

Climatographs

A visual representation of a region's average monthly temperature and precipitation.

Temperate Grasslands

Dominated by grasses; trees and large shrubs are absent. Temperatures vary more from summer to winter, and the amount of rainfall is less than in savannas. This biome has hot summers and cold winters.

Temperate Rainforest

Has heavy rainfall and features coniferous trees such as cedars, spruces, hemlocks, and douglas fir. Forest interior is shaded and damp, moisture loving animals such as the banana slug are most common. The soils are quite fertile, but are susceptible to landslides and erosion if forests are cleared.

Tropical Rainforest

A biome that receives large amounts of rain. The most biologically diverse of all biomes. Half of our Earth's species live here, Broadleaf ever evergreen forest found in wet and hot regions near the equator, A biome that is characterised by extreme productivity, high solar radiation, and regular rainfall

Tropical Dry Forest

A biome that consists of deciduous trees and occurs at tropical and subtropical latitudes where wet and dry seasons each span about half the year, characterized by relatively high temperatures and precipitation overall but with a pronounced dry season lasting around 7 months.

Savanna

A tropical grassland biome with scattered individual trees and shrubs, large herbivores, and three distinct seasons based primarily on rainfall, maintained by occasional fires and drought.

Desert

A type of biome characterized by low moisture levels and infrequent and unpredictable precipitation. Daily and seasonal temperatures fluctuate widely, A region of vegetation, either cold or hot, that receives ten inches or less of precipitation each year.

Tundra

A biome at the northernmost limits of plant growth and at high altitudes, characterized by dwarf woody shrubs, grasses, mosses, and lichens., A vast, level, treeless plain in the arctic regions. The ground beneath the surface of the tundras is frozen even in summer.

Boreal Forests

A forest made up primarily of coniferous evergreen trees that can tolerate cold winters and short growing seasons, Stretches across the north of the northern hemisphere. Very cold winters, short, cool summers, and extraordinarily high annual variation in temperature confers are the dominant plants.

Chapparal

A scrubland biome of dense, spiny evergreen shrubs found at midlatitudes along coasts where cold ocean currents circulate offshore; characterized by mild, rainy winters and long, hot, dry summers