Whenever my wife and I go to London, we always stay at the same hotel in Kensington. Our favorite pub, The Goat, is nearby on Kensington High Street. Not too long ago, I recall sitting with Pete Olson and one of his postdocs in our pub enjoying a pint of lager. Pete, his postdoc, and I were talking about the Journal of Parasitology and some of what goes on in terms of editing. During the conversation, I mentioned that the only really contentious issues that have arisen over the years generally involved confrontations between referees and authors concerned with systematics/phylogenetics papers. I said to Pete, “Aside from natural personality clashes between certain folks, why do you suppose this is the case?” Pete responded immediately, like he knew the question was coming and had prepared an answer in advance. He said, “This is the only area of parasitology where opinion is acceptable in print form.”

When Pete said this, I knew exactly what he meant, because when one thinks about it, a genus and species is really nothing more than a hypothetical construct. It is an opinion, well considered and documented in most cases, but still an opinion. When dealing with hypotheses, people will often have different ideas about them.