定义：a fruit which develops from a carpel and at maturity comprises a dry exocarp, dry mesocarp, and dry endocarp that are elongated into a wing-like structure.
定义：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.
定义：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)
