You should probably clarify what you mean by species, since there are several different definitions that biologists use.
The intuitive definition is phenotypic similarity. The problem with this definition is that it isn't too objective.
The definition which is most used by biologists is the Biological Species Concept, which states that a species is a reproductively isolated population.
There are examples of both of these getting created within the human experience. You must realize, though, that "species" doesn't have a firm foundation within the evolutionary framework, since according to evolutionary theory all life is a branching continuum. This actually gives us insights as to why it is so hard to define "species", since that would be trying to dichotomize a continuum.
This message has been edited by JustinCy, 01-13-2005 21:26 AM
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