This study was of the events following a defaunation event on six islands of the coast of the Florida Keys, each island consisting of one or several mangroves. Simberloff and Wilson suggest that given time the population of species on each island will reach a predictable dynamic equilibrium consisting of a similar but constantly changing cast of species.

The issues I found with this research were several. The authors conducted only a single survey of each island plus two controls before the experiment began and used this is an assumed average species number on each island, a sample size far too small from which to draw any conclusions. Beginning from this survey, any information they glean about average species numbers may match up to an anomalous “average” and wrongfully confirm their theories. Throughout the experiment, the collection of data was too infrequent given the ephemeral nature of many of the species involved. The experiment also ended before any of the islands populations were found to have arrived at a dynamic equilibrium, so any similarity between the pre-defaunation survey and the final survey could be a case of a broken clock being “right” twice a day, in this case, right meaning supporting the theory put forward in the paper. Finally, there is no indication that the two control islands were surveyed more than once before and once after the experiment, which would have given a much clearer view of the properties and typical variance of a dynamic equilibrium.

Aside from the conduct of the experiment, I found the writing to be a bit lacking. I would have found technical details on how the surveys were conducted, and where each island was located relative to a source and each other to be helpful in filling out my understanding of the theory.

My feeling toward this essay isn’t that the authors’ theory is incorrect, it’s that the way the experiment was conducted left didn’t find conclusive enough evidence to confirm it.