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(The Victorian Web)

Geerat Vermeij and I just published a new paper in Paleobiology, entitled ” Reining in the Red Queen: The dynamics of adaptation and extinction re-examined.” The paper is partly a follow-up to my earlier paper on the Red Queens Hypothesis, reported previously in these posts (here and here), and partly the result of a discussion started between Vermeij and myself while attending the workshop that resulted in this paper on state transitions in the global biosphere. Here we argue that some of the fundamental assumptions of the hypothesis are flawed and that it therefore likely holds only under restricted circumstances. The full reference and abstract follow.

Vermeij, G. J. and P. D. Roopnarine. 2013. Reining in the Red Queen: The dynamics of adaptation and extinction re-examined. Paleobiology 39:560-575.

Abstract

One of the most enduring evolutionary metaphors is Van Valen’s (1973) Red Queen. According to this metaphor, as one species in a community adapts by becoming better able to acquire and defend resources, species with which it interacts are adversely affected. If those other species do not continuously adapt to compensate for this biotically caused deterioration, they will be driven to extinction. Continuous adaptation of all species in a community prevents any single species from gaining a long-term advantage; this amounts to the Red Queen running in place. We have critically examined the assumptions on which the Red Queen metaphor was founded. We argue that the Red Queen embodies three demonstrably false assumptions: (1) evolutionary adaptation is continuous; (2) organisms are important agents of extinction; and (3) evolution is a zero-sum process in which living things divide up an unchanging quantity of resources. Changes in the selective regime need not always elicit adaptation, because most organisms function adequately under many ‘‘suboptimal’’ conditions and often compensate by demonstrating adaptive flexibility. Likewise, ecosystems are organized in such a way that they tend to be robust and capable of absorbing invasions and extinctions, at least up to a point. With a simple evolutionary game involving three species, we show that Red Queen dynamics (continuous adaptation by all interacting species) apply in only a very small minority of possible outcomes. Importantly, cooperation and facilitation among species enable competitors to increase ecosystem productivity and therefore to enlarge the pool and turnover of resources. The Red Queen reigns only under a few unusual circumstances.

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