Definition: Common species and uncommon species are designations used in ecology to describe the population status of a species. Commonness is closely related to abundance. Abundance refers to the frequency with which a species is found in controlled samples; in contrast, species are defined as common or uncommon based on their overall presence in the environment. A species may be locally abundant without being common.
Definition: Symbiont transmission maintains symbioses through host generations. In vertical transmission, the symbiont is inherited from the mother or, more rarely, from both parents.
