A species is what a taxonomist says it is

The Economist has a nice op-ed piece in it this week on taxonomic inflation -- how conservation minded taxonomists have had a tendency of late to reclassify subspecies as species (a suspiciously large number of which occur in the charismatic megafauna groups) in order to intensify the perceived threat of extinction, increase the biodiversity of a habitat and ramp up its claims for protection. The basic idea being that this sort of inflation will inevitably lead to devaluation, which is no good for species. Of course deciding on what is or is not a species can be awfully tricky, but the bottom line is this:

"... a species is what a taxonomist says it is. Evolution often fails to produce the clear divisions that human thought in general, and the law in particular, prefers to work with. It therefore behoves taxonomists to be honest. If they debase their currency, it will ultimately become valueless. Linnaeus the economist would have known that instinctively."

Good advice.

Link to article