The cover of Anolis Newsletter III, supposedly resembling Ernest Williams

“It was while walking along a hedge row in the Dominican Republic, listening to a complaint that I and some of my co-workers did not frame hypotheses every day while in the field, that I invented (or recognized) the PRINCIPLE OF UNSYMPATHETIC MAGIC. This states that, if one arrives at any firm and vivid conviction about matters of fact or theory in the field, the NEXT observation will provide a contradiction.

“The principle is easily confirmed by any field worker. Note, however, that NATURE IS NOT DECEIVED. No opinion merely pretended to, i.e. not held with fierce conviction, will be responded to by a conclusive observation. The MALICE OF NATURE prohibits the PRINCIPLE OF UNSYMPATHETIC MAGIC from being a source of satisfaction to the field worker.”

—Ernest E. Williams in “The Third Anolis Newsletter,” 1977.

The Principle of Unsympathetic Magic, once you’ve learned of it, surfaces everywhere. My most recent experience with the principle occurred during a trip to the Cayman Islands. On Cayman Brac, we were finding variation in the dewlap color of A. sagrei, with some populations being yellow and some populations being orange. We felt that we had grasped a pattern in the color variation – lizard populations near human habitation tended to have more orange dewlaps compared to populations farther from human habitation. We had hypothesized that orange dewlaps were the result of hybridization between the endemic yellow-dewlapped A. sagrei luteosignifer and occasional red-dewlapped A. sagrei sagrei vagrants that were likely stowing away in supply shipments delivered by barges coming from Grand Cayman.

This hybridization hypothesis generated two predictions: (1) we expected that we would find orange-dewlapped populations near the port, and (2) we doubly expected that we would find orange-dewlapped populations at the island’s plant nursery.

(The best place to find anole populations at the beginning of an invasion, at least in Houston and Corpus Christi, is the garden section of Home Depot. Moreover, there are anecdotes of anoles popping out of potted plants here in Boston.)

The Principle of Unsympathetic Magic, however, ensured that on Cayman Brac yellow dewlaps were very common at the port and the only game in town at the plant nursery (although the hybridization hypothesis remains to be directly tested).

If you have any memorable experiences where the Principle of Unsympathetic Magic held (or didn’t hold) for you, share them in a comment. Also, take a look at the Anolis Newsletters. They are an informal collection of Anolis research spanning 1972-2010. The beginning of Newsletter V contains short history of the newsletters. It also contains a few remembrances of Williams, to whom Newsletter V is dedicated.

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