Having small population size is a characteristic almost universally inherent to apex predators, humans and dogs by far the most blatant exceptions. Low numbers wouldn't be a problem for apex predators if there was an abundance of prey and no competition or niche overlap, a scenario that is rarely, if ever, encountered in the wild. The competitive exclusion principle states that if two species' ecological niches overlap, there is a very high likelihood of competition as both species are in direct competition for the same resources. This factor alone could lead to the extirpation of one or both species, but is compounded by the added factor of prey abundance.