Thursday, 13 June 2013

Part 2: George Williams contradicts the Red Queen hypothesis

[Update: 15.07.2017: See also this article on the implications this ignored challenge by George Williams of the parasite red-queen theory has for science and its historiography: Joachim L. Dagg: How counterfactuals of Red-Queen theory shed light on science and its historiography. Studies in History and Philosophy of Biological and Biomedical Sciences 64: 53-64. The article will be freely available at this link up to 22 August 2017.]

Before George Williams got explicit about his reservations against the Red Queen hypothesis in 2000 (see previous post), he published a book called The Pony Fish's Glow (Williams 1997, Basic Books). It contains the same argument, yet the contradiction to the Red Queen hypothesis is not stated explicitly.

For sessile organisms with offspring that do either disperse or remain close to the parent (many plants, corals etc.) he states:
"If the offspring are to develop immediately near the parent, asexual reproduction is the rule, with structures such as runners or tubers. If the offspring are to be broadcast far and wide into an unknown diversity of new habitats, sexual seed production is what we find." Williams (1997, p. 80)
"A healthy herbaceous perennial plant in a weedy field has successfully coped with a particular array of parasites, insect pests, and competing plants. In producing offspring that will grow up close by in the same conditions, it uses its vegetative asexual process. If it is to produce offspring that must compete with the unknown exploiters and competitors many meters away, it will start them off as sexually diversified seeds." Williams (1997, p. 81)
This is the opposite of what we'd expect under the Red Queen hypothesis. The Red Queen hypothesis assumes that there is no way to cope successfully with an array of parasites and pests for several generations. Therefore, the offspring remaining close to the parent should be produced sexually and the dispersers asexually.

Maybe it would have been too scrupulous to be more explicit about this disagreement with W.D. Hamilton in a popular science book.