A study out today in PLoS Biology finds that termites create oases of biological richness in the African savanna.
It came about because when biologist Todd Palmer, one of the authors on the paper, first got to Africa in 1997, he was researching ants, not termites. Acacia ants, specifically, because three species of them, Crematogaster nigriceps, C. mimosae, and C. sjostedti, all live in symbiosis with acacias.
But as he crawled around scrubby patches of acacia drepanolobium (known as the whistling thorn), he couldn't help but notice that the lushest pockets of the trees tended to cluster around a ring of grass that contained no trees.
It wasn't until another researcher, this time a termite expert from Oxford University in England, came to visit that what he was seeing became clear. She took one look at the rings and said "Those are termite nests."
Most Americans, Palmer among them, have an image of African termite mounds as being tall, pillar-like objects made of red dirt. But in central Kenya the odontotermes montanus termite builds underground mounds that especially in times of drought don't look much different from the rest of the savanna.
"They were literally invisible to me," he says.
But when the drought lifted, the rings quickly become greener and more productive than the surrounding area, standing out like "little pricks of green" as you fly over them, says Palmer. Not only that, but they definitely appeared in a uniform 'polka dot' arrangement.
Palmer, and many others, wondered "that's not a human-made feature, how did these get to be so regular?" What he and fellow researchers writing in this week's edition of the journal PLoS Biologyfound was that localized interactions between species scale up to create specific patterns.
What they showed was the extent to which one species can alter the entire structure and function of an entire ecosystem -– and literally under the noses of ecologists for years, a pattern that was invisible until someone, or a bunch of someone's, started actually paying attention to it.
Source: USA Today