I have been working on a long term project to assess diversity in local forests (in Mississippi). One of the problems that is always bothering me is what seems to be excessive taxonomic splitting, especially with taxa like Oaks. Black Oak, Water Oak, Blackjack Oak, a polytypic species that has occupied a number of niches, or three separate species? How about Post Oak and Swamp Post Oak, two species? Chestnut Oak and Swamp Chestnut Oak? It seems the polytypic species idea is as dead as it's author!
So what happens is that if I go into a community with a good Oak representation, I get more "diversity" than an area with more Hickory, Sweetgum and Magnolia ...but is it more diverse, or really less diverse? I could look at just genera, but then the oaky areas look less diverse; after all, a Red Oak and a White Oak are at least different species (but is a Cherrybark Oak really a different species from a regular Red Oak?). Is there some way to mitigate the effect of taxonomic splitting in some of these lineages? "So easy it seemed once found, which yet unfound most would have thought impossible" John Milton ________________________________________ Robert G. Hamilton Department of Biological Sciences Mississippi College P.O. Box 4045 200 South Capitol Street Clinton, MS 39058 Phone: (601) 925-3872 FAX (601) 925-3978
