organismgrupp

Organismgrupp is a term used primarily in Swedish biology and ecology to refer to a group of organisms that are grouped together on the basis of shared characteristics, ecological role, or evolutionary relationships. Unlike formal taxonomic ranks such as species or family, an organismgrupp is not a single mandatory rank; it is a conceptual grouping that can be defined by researchers for a particular purpose. The criteria for forming an organismgrupp may be morphological similarity, genetic relatedness, ecological function, behavior, or a combination of these factors. In ecological studies, the term is often used to describe functional groups or guilds, such as producers (photosynthetic organisms), herbivores, carnivores, omnivores, and decomposers, or more specific groups like pollinators or detritivores.

In taxonomy or paleontology, it can refer to clusters of related organisms recognized within a study, sometimes aligned with, but not identical to, formal ranks. Determining an organismgrupp can involve various methods: morphological analysis, DNA sequencing and phylogenetics, or assessment of ecological roles and life histories. The concept is useful for analyzing biodiversity, food webs, energy flow, and ecosystem services without committing to rigid taxonomic boundaries. However, because the grouping criteria are subjective and context-dependent, different researchers may define different organismgrupper for the same set of organisms.

See also: taxonomic rank, ecological guild, functional group.