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Re: Hanson 2006, Mortimer, Baeker response

Nick Pharris wrote:

There are those who would consider encoding relative rank in the ending on the name a good and useful thing.

The problem is that, with phylogenetic definitions, the relative 'rank' (as implied by the suffix) has to be consistent with the definition. If you want to encode relative rank, then clades ending in -oidea, -idae, -inae, -ini have to be defined in such a way that they they don't become more inclusive than clades of lesser or equal 'rank'.

For example, if we wanted to name and define a clade Microraptorinae, we would have to frame the definition such that Microraptorinae would never include Dromaeosauridae, Dromaeosaurinae or Velociraptorinae. Similarly, Diplodocoidea, Diplodocidae, Diplodocinae, and Diplodocini must be defined such that (a) each is a subset of the one before (in terms of content); and (b) they cannot include clades of equal or greater 'rank' (as denoted by the suffix). On the other hand, Diplodocimorpha is free to go wherever it wants, because it has no Linnaean baggage.

This isn't just a theoretical problem. Senter (2004) discussed this problem with respect to dromaeosaurid nomenclature, when he wanted to name a new clade for _Microraptor_ and its closest relatives. He studiously avoided naming his new clade either Microraptoridae or Microraptorinae, because he foresaw that changes in topology (i.e., relative position of _Microraptor_ vs _Dromaeosaurus_) could put Microraptoridae inside Dromaeosauridae - and he didn't want that. Instead Senter opted for the name Microraptoria. Without a suffix to denote 'rank', Microraptoria can be above or below Dromaeosauridae and/or Dromaeosaurinae. But Dromaeosaurinae has to be *within* Dromaeosauridae.