There isn't much to see on the long drives to and from Houston either, but Holland said hours of solitude provide a valuable time for thinking and synthesizing what he's learned in the desert. That's important because his ultimate goal reaches far beyond the Sonoran Desert to a fundamental rethinking of ecological theory for such mutualistic interactions.
"I develop theoretical models, equations that attempt to explain mutualistic relationships like the one between the moth and the cactus, and I take those models into the field and examine them empirically to find out how well they predict what really happens," Holland said.
Traditional theory of such mutualistic interactions leads to predictions of unbounded population growth or instability and eventual doom due to one species overexploiting another. These predictions clearly don't square with what Holland and his students see happening in the Sonoran Desert, where both species thrive. Holland's models differ from traditional theory, suggesting that one mutualist may exert some control over the other's population increases, such that neither unbounded growth nor overexploitation ensue.
"I have always been interested in the community ecology of mutualism -- the larger puzzle -- and this moth-cactus relationship is just one piece of that," Holland said. "When we discovered the relationship in 1995, I immediately thought of using it to look at the bigger picture. But in aiming to do that, I wound up spending a decade working on the population ecology of mutualisms, a prerequisite for then understanding this larger puzzle."
Having made some progress on the population ecology of mutualism, some of Holland's current work, which is slated for publication later this year, returns to his earlier interests in community ecology. "We want to understand how the structure of mutualistic communities in
|Contact: Jade Boyd|