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NFC: Gambrosia, not Damnbusia
On Gambusia:
Oh so maligned. And why?
For exuberant fecundity (not a crime)?
How shameful not to respect the weeds.
Like a ragweed (Ambrosia spp.) or dandelion (Taraxacum spp.), Gambusia multiply and cover the face of a continent, ever expanding into new environments. And in each place colonized, potentially a seed... a seed for organic diversification of the highest order.
At first, an isolated few become adapted to their new milieu. Then iimmigration (gene flow) from the common stock is a liability. So adapted populations learn (evolutionarily) to shun potential mates from the ancestral pool. The pioneers become ever more genetically (and phenotypically) different from the founders. Lo, a new species. A triumph... Endemism!
So now we have new and different forms: Gila topminnow, San Marcos topminnow, Gambusia this, Gambusia that. Hooray and gratitude for the weed.
So how to regard the wellsprings of diversification? If not awe, perhaps a simple respect.
Thom DeWitt
____________________________________________________
Dr. Thomas J. DeWitt
Department of Wildlife & Fisheries Sciences
Texas A&M University
2258 TAMU
College Station, TX 77843-2258
Tel. 979/458-1684; Fax 979/845-4096; E-mail tdewitt at tamu_edu
http://wfscnet.tamu.edu/faculty/dewitt/webpage.htm