Community (ecology)
An ecological community is an assemblage of populations of different species that live in the same area and interact with one another. Communities are characterised by their species composition, diversity, and the web of interactions such as predation, competition, and mutualism. The study of communities examines how these interactions shape the structure and stability of ecosystems over time.
Types of Species Interactions in a Community
| Interaction | Species A Effect | Species B Effect | Example |
|---|---|---|---|
| Mutualism | Positive (+) | Positive (+) | Bee and flower (pollination) |
| Commensalism | Positive (+) | Neutral (0) | Barnacles on whale skin |
| Predation | Positive (+) | Negative (−) | Lion eating a zebra |
| Competition | Negative (−) | Negative (−) | Two plant species for sunlight |
| Parasitism | Positive (+) | Negative (−) | Tapeworm in a host intestine |
Interactive Tools
Wikimedia Commons, CC BY-SA
Related Terms
Ecosystem
An ecosystem is a biological community of interacting organisms together with the physical environment they inhabit, including all living (biotic) and non-living (abiotic) components. It represents a functional unit of ecology where energy flows and nutrients cycle between organisms and their environment. Ecosystems range in scale from a small pond to the entire Amazon rainforest and are the foundational units studied in ecology.
Population (ecology)
In ecology, a population is a group of individuals of the same species living in the same geographic area at the same time and capable of interbreeding. Population ecology studies how populations change in size and composition over time, driven by birth rates, death rates, immigration, and emigration. Understanding populations is essential for conservation biology, fisheries management, and predicting the spread of invasive species.
Food Web
A food web is a complex network of interconnected food chains within an ecosystem, showing all the feeding relationships among organisms and the multiple pathways through which energy and nutrients flow. Unlike a simple linear food chain, a food web more accurately represents real ecosystems where most organisms eat more than one type of food and are eaten by more than one predator. Food webs are used to model the cascading effects that result from changes in species populations, such as the removal of a keystone species.
From Latin communitas (fellowship, community), derived from communis (common, shared). In ecology, the term describes species sharing a common habitat and has been in formal use since the work of Frederic Clements and Henry Gleason in the early 1900s.