More on the mysterious mangoes of western Panama

In his thorough essay of yesterday, Matt Miller sheds some light on the big mess that is field separation (or lack thereof) of the mangoes of western Panama. Read on, dear readers, if you dare.
The bottom line: range simply cannot be used to separate Green-breasted Mango from Veraguan Mango, as specimens of both types have been obtained in both slopes, sometimes from the same site at the same time. Adult males are different enough, but we don't know nothing about no fieldmarks for no females nor juveniles, and there may not be any. The only sure way to establish if there are differences (or if Veraguans and Green-breasteds are too much of the same thing to be called different species) is to obtain a bigger sample, i.e. get more specimens, which will probably horrify them birders; but here at Xenornis we're all in favor of the advancement of science, especially if it gets us more ticks in our life lists.
Matt's contribution to the blogosphere, Neo-Ornithology, promises a weekly series of similar essays on the unsuspected depths of Panamanian bird identification, and will definitely become the resource of choice for when you need a good humbling.