Community Ecology and Species Interactions

Flashcards covering key vocabulary and concepts related to community ecology, species interactions, and ecological succession.

Competition (-/-)

Two or more species compete for a resource that is in short supply.

Exploitation (+/-)

One species benefits by feeding upon the other species, which is harmed; includes predation, herbivory, and parasitism.

Predation

One species, the predator, kills and eats the other, the prey.

Herbivory

An herbivore eats part of a plant or alga.

Parasitism

The parasite derives nourishment from a second organism, its host, which is harmed.

Mutualism (+/+)

Both species benefit from the interaction.

Commensalism (+/0)

One species benefits, while the other is not affected.

Community

A group of species living together at the same place and time.

Community Ecology

The study of the factors that structure communities; focuses on patterns of species composition & relative abundance.

Guild

A group of species that use similar resources.

Functional Group

Species that function in similar ways but may or may not use similar resources.

Community Structure

Patterns of species diversity and composition at the community or local scale.

Foundation Species

Species that are large or abundant and affect community structure by providing habitat and food for other organisms.

Species Richness

The number of different species in the community.

Relative Abundance

The proportion each species represents of all individuals in the community.

Trophic Structure

The feeding relationships between organisms in a community.

Trophic Level

The position an organism occupies in a food chain.

Keystone Species

Species that have disproportionately large effects on the community relative to their abundance or biomass.

Ecosystem Engineers

Species that cause physical changes in the environment that affect community structure.

Bottom-Up Control

Nutrient supply or the availability of food at lower trophic levels limits the abundance of organisms at higher trophic levels.

Top-Down Control

The abundance of organisms at higher trophic levels controls the abundance of organisms at lower trophic levels.

Disturbance

An event that changes a community by removing organisms from it or altering resource availability; creates opportunities for new individuals to become established.

Ecological Succession

The pattern of colonization and species replacement that occurs in a community following a severe disturbance.

Primary Succession

Succession on landforms not previously influenced by species (e.g., lava flows, freshly formed dunes).

Secondary Succession

Succession on landforms where vegetation has been partially or completely removed, but well-developed soils, seeds, & spores remain.