John Ray - Ray's Definition of Species

Ray's Definition of Species

Ray was the first person to produce a biological definition of what a species is. This definition comes in the 1686 History of plants:

"... no surer criterion for determining species has occurred to me than the distinguishing features that perpetuate themselves in propagation from seed. Thus, no matter what variations occur in the individuals or the species, if they spring from the seed of one and the same plant, they are accidental variations and not such as to distinguish a species... Animals likewise that differ specifically preserve their distinct species permanently; one species never springs from the seed of another nor vice versa".

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