plbi-08-05-Pringle

A soldier Odontotermes termite patrols a bit of fungal comb that has been removed from a mound. Although these termites spend their lives underground and are rarely seen, their activities support the biodiversity of African savannas. ((Robert Pringle) )

The king of the African savanna is not the lion — it is the tiny termite, say ecologists who have found the insect is central to ecosystem productivity.

Quirks & Quarks

Listen to Bob McDonald's  interview with study co-author Tod Palmer  from the University of Florida, from the May 29th edition of Quirks & Quarks.

The finding, published this week in the journal PLoS Biology, confirms that 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," Robert Pringle, a research fellow at Harvard University and the study's lead author, said in a release.

Pringle's curiosity was sparked after noticing Kenya dwarf geckos seem to converge around the termite mounds, which can grow up to 10 metres in diameter over the course of centuries.

Pringle and his colleagues looked more closely and found that there were not only an unexpectedly large number of lizards hanging about, but also a lot of other animals and plants.

Moreover, plants grew more quickly the closer they were to the mounds. And also the number of animals and their reproductive rates increased the closer they were to the termites.

"Termites are typically viewed as pests, and as threats to agricultural and livestock production," Pringle said. "But productivity — of both wild and human-dominated landscapes — may be more intricately tied to the pattern-generating organisms of the larger natural landscape than is commonly understood."

He and his colleagues also looked at satellite imagery, finding that each mound was the centre of a burst of flowers. The images also showed the mounds were evenly dispersed as if they were squares spaced about 60 to 100 metres apart on a giant checkerboard.

The researchers believe the checkerboard pattern optimizes the overall productivity of the ecosystem. They also suspect the reason for mound-centred bursts of life is that termites carry coarse particles into the otherwise fine soil around their mounds.

These coarser particles let life-giving water filter into the soil and discourage disruptive shrinking and swelling of topsoil from repeated cycles of rain and drought.

The researchers say conservationists trying to restore degraded habitats might consider creating patterns of floral and faunal richness.