Population and Community Ontology (PCO)

The Population and Community Ontology (PCO) describes material entities, qualities, and processes related to collections of interacting organisms such as populations and communities. It is taxon neutral, and can be used for any species, including humans. The classes in the PCO are useful for describing evolutionary processes, organismal interactions, and ecological experiments. Practical applications of the PCO include community health care, plant pathology, behavioral studies, sociology, and ecology.

Open in the Ontology Lookup Service (OLS)


collection of organisms [PCO_0000000]

A material entity that consists of two or more organisms, viruses, or viroids. A group of organisms of the same taxonomic group grouped together in virtue of their sharing some commonality (either an inherent attribute or an externally assigned role). May be of the same or different species.

ecological community [PCO_0000002]

A multi-species collection of organisms of at least two different species, living in a particular area. Must have at least two populations of different species as members. Ecological community is defined broadly here, but includes both ecological interactions (inherited from parent term community) and spatial co-existence. It may be used to describe every organisms living in an area, but is often used to refer only to organisms of a particular taxon or guild (e.g., the plant community, the insect community, the herbivore community). The word community, as it often used to describe a group of humans living together, is a type of single-species collection of organisms, not an ecological community.

family [PCO_0000020]

A domestic group, or a number of domestic groups linked through descent (demonstrated or stipulated) from a common ancestor, marriage, or adoption.

multi-species collection of organisms [PCO_0000029]

A collection of organisms that consists of two or more organisms from at least two species.

organismal entity [PCO_0000031]

A material entity that is one or more organisms, viruses or viroids.

pair of interacting organisms [PCO_0001000]

A collection of organisms that consists of exactly two organism, viruses, or viroids that are interacting with each other.

population of organisms [PCO_0000001]

A collection of organisms, all of the same species, that live in the same place. It is sometimes difficult to define the physical boundaries of a population. In the case of sexually reproducing organisms, the individuals within a population have the potential to reproduce with one another during the course of their lifetimes. ‘Community’, as often used to describe a group of humans, is a type of population of organisms. Classes for population already exist in IDO (‘organism population’, IDO_0000509) and OBI (‘population’, OBI_0000181). The definitions should be standardized across OBO Foundry ontologies and only one term used.

single-species collection of organisms [PCO_0000018]

A material entity that has as parts two or more organisms, viruses, or viroids of the same species and no members of any other species.


Last modified January 5, 2022: adding PCO (888b06d)