In Brazil backlands, termites built millions of dirt mounds

PALMEIRAS – Roy Funch, an American botanist who has lived and worked in Brazil’s hardscrabble northeast for decades, long looked at huge cone-shaped mounds of mud in the distance and wonder.

What built them? How many were there? How long had they been there?

After years of failing to generate interest in the mounds, a chance meeting with an English expert on social insects, Stephen Martin, led to remarkable discoveries: there are over 200 million mounds built by termites that stretch across 88,800 square miles, about the size of Great Britain. 

What’s more, some of the dirt heaps are nearly 4,000 years old.

“While the Romans were building their columns, their buildings, these termites were building their mounds,” Funch said, adding that the dirt piles represent the largest bioconstruction of any species other than humans.

The mounds, seen in various places in a vast desert-like region called the Caatinga, stand between six and 13 feet high and are spaced roughly equally apart – between 52 and 72 feet.

To landowners who clear brush to plant crops, the mounds are a nuisance. Bulldozing them is difficult because over years of being baked in the hot sun, the already-hard dirt and clay become like stone. Poor people in the area use chunks of the mounds to build adobe houses.

Funch says he wrote two articles about the mounds in Brazilian publications, but they didn’t draw any attention. Without expertise in insects or the world of scientific publishing, he wasn’t sure how to take his research to the next level.

Asking local people didn’t help.

“Some would say they are termites, some would say ants, some would say: ‘Well, they have always been there. They are part of nature,’” Funch said.