CAMBRIDGE, Mass. -- The majestic animals most closely associated with the African savanna -- fierce lions, massive elephants, towering giraffes -- may be relatively minor players when it comes to shaping the ecosystem.
The real king of the savanna appears to be the termite, say ecologists who've found that these humble creatures contribute mightily to grassland productivity in central Kenya via a network of uniformly distributed colonies. Termite mounds greatly enhance plant and animal activity at the local level, while their even distribution over a larger area maximizes ecosystem-wide productivity.
The finding, published this week in the journal PLoS Biology, affirms a counterintuitive approach to population ecology: Often it's the small things that matter most.
"It's not always the charismatic predators -- animals like lions and leopards -- that exert the greatest control on populations," says Robert M. Pringle, a research fellow at Harvard University. "As E.O. Wilson likes to point out, in many respects it's the little things that run the world. In the case of the savanna, it appears these termites have tremendous influence and are central to the functioning of this ecosystem."
Prior research on the Kenya dwarf gecko initially drew Pringle's attention to the peculiar role of grassy termite mounds, which in this part of Kenya are some 10 meters in diameter and spaced some 60 to 100 meters apart. Each mound teems with millions of termites, who build the mounds over the course of centuries.
After observing unexpectedly high numbers of lizards in the vicinity of mounds, Pringle and his colleagues began to quantify ecological productivity relative to mound density. They found that each mound supported dense aggregations of flora and fauna: Plants grew more rapidly the closer they were to mounds, and animal populations and reproductive rates fell off appreciably with greater distance.
What was observe
|Contact: Steve Bradt|