A species may be defined as a group of organisms of interbreeding natural populations that are reproductively isolated from other groups and that share in common gene pools.

• 物种是生物界发展的连续性与间断性统一的基本间断形式；在有性生物物种呈现为统一的繁殖群体，由占有一定空间，具有实际或潜在繁殖能力的种群所组成，而且与其他这样的群体在生殖上是隔离的。