In Brazil backlands, termites built millions of dirt mounds

(5 Dec 2018) LEADIN: In Brazil’s rugged northeast, termites built millions of mounds that remained hidden in plain sight until a chance meeting of a botanist and insect expert led to remarkable discoveries. Over 200 million mounds stretch across an area the size of Great Britain. Testing found that some of the dirt heaps are almost 4,000-years-old. STORYLINE: For years, American botanist Roy Funch would look at huge cone-shaped mounds of mud in the distance and wonder. What species built them? How many were there? How long had they been there? After years of failing to garner wider interest, Funch’s chance meeting with an English expert on social insects, Stephen Martin, would lead to remarkable discoveries: built by termites, there are over 200 million mounds that stretch across of 88,803 square miles (230,000 square kilometres), about the size of Great Britain. What’s more, some of the dirt heaps are nearly 4,000-years-old. “It’s the greatest construction project of any species visible that we know of besides humans,“ says Funch, who initially came to Brazil as a Peace Corps volunteer in 1977 and stayed. “It’s been hiding here for hundreds, thousands of years and only recently has it become really known to science. So, it’s a fantastic discovery in that sense. It was here, but it wasn’t known. “It’s like a Mayan temple in the forest. It was there, but we didn’t know about it.“ The mounds, seen in various places in a vast desert-like region called the Caatinga, stand between six and 13 feet (two to four metres) high and are roughly spaced apart equally - between 52 and 72 feet (16 to 22 metres). Funch says he wrote two articles about the mounds in Brazilian publications, but they didn’t lead to anything else. Without expertise in insects or the world of scientific publishing, he wasn’t sure how to take his research to the next level. That all changed when Funch met Stephen Martin, an entomologist at the University of Salford in England. A few years ago, Martin was in northeast Brazil studying honey bees and ants in the state of Bahia. He too was curious about the mounds. By chance, Martin and Funch met next to a river in Lencois, a small town in the northeastern state of Bahia that is about 30 (50 kilometres) west of the beginning of the mounds. The two teamed up, and their research was published on 19 November in “Current Biology.“ The pair concluded the mounds were built by Syntermes dirus, a large termite species that feeds on leaves and lives underground. While the termites are found in the region, they did not find them actively working in the larger mounds, but instead along the edges of areas with mounds. Cutting into several mounds to examine further, they found only a small tube-like hole going to the top of each one, not an extensive pattern of tunnels throughout. That suggested the termites were simply finding a place to chuck earth from underground, where they build their tunnels. “There was no architecture, just throwing it out. So, it formed these cones on the ground,“ explains Funch. In more humid areas where the same species live, such as the Amazon, mounds they create are eroded by rain and wind. But in the Caatinga eco region, there is rainfall only for a few weeks a year. Like the earth, the vegetation is rough: xeric shrub land and thorny trees that shed leaves seasonally. That vegetation covers and camouflages the mounds in large swaths of the area, one of the reasons they were essentially hiding in plain sight. Funch says improvements in Google Earth’s imaging in recent years helped understand the extent of the formations. Find out more about AP Archive: Twitter: Facebook: ​​ Instagram: You can license this story through AP Archive: