定義： Living in the fluid medium (water or air) but unable to maintain their position or distribution independently of the movement of the water/air mass (adapted from Lincoln et al., 1998).
定義： An interaction relationship involving a predation process, where the subject kills the target in order to eat it or to feed to siblings, offspring or group members
定義： This organism produces this material or substance, either during its life or after death. A produces B if some process that occurs in A has output B.
定義： A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)
