寄生 Parasitism
寄生，即兩種生物在一起生活，寄生物受益，寄主受害，後者給前者提供營養和居所。寄生物的體積比寄主小，不會殺死寄主，但會消耗寄主體內的養份。
Parasitism is a symbiotic relationship between species, where one species, the parasite, benefits at the expense of another species, the host. The parasite is generally smaller than the host, and do not kill the host. But they will reduce their biological fitness by exploiting hosts for nutrients.
