A huge complex of around 200 million termite mounds has been discovered to cover an area the size of Great Britain in a remote area in northeastern Brazil.
The mounds, some of which are up to 13ft (four metres) tall, are up to 4,000 years old, and while they are visible on Google Earth, they are largely hidden from view at ground level as they cover an area which is largely semiarid, thorny-scrub forests.
"These mounds were formed by a single termite species that excavated a massive network of tunnels to allow them to access dead leaves to eat safely and directly from the forest floor," researcher and entomologist Professor Stephen Martin from the University of Salford said.
The scientists also estimated that to build 200 million mounds, the termites excavated 2.4 cubic miles of dirt, enough to build 4,000 Great Pyramids of Giza.
“This the greatest known example of ecosystem engineering by a single insect species,” the scientists wrote.
The mounds, many of which are still being built, came to scientists' attention when some of the land was cleared for pasture in recent decades, making them more visible.
Prof Martin first became interested in the mounds when travelling to Brazil to research honeybees and spotting the endless cones.
While they might look like nests, the mounds are actually just cones of earth resulting from the termites' slow and steady excavation of a network of interconnected underground tunnels.
The mounds are the work of Syntermes dirus, among the largest termite species at about half an inch (1.3cm) long.
The mounds are spaced on average about 60ft (20m) apart.
According to the research published in November's edition of Current Biology, the vast tunnel network allows the insects safe access to a food supply of dead leaves on the forest floor.
"It's incredible that, in this day and age, you can find an 'unknown' biological wonder of this sheer size and age still existing, with the occupants still present," Prof Martin said.
The fact that the oldest of the mounds date back nearly 4,000 years means that they are the same age as some of the world's oldest known termite mounds in Africa.
The researchers said there are still many unanswered questions about the termite colonies, including the exact physical structure of the nests, and the fact that no queen chamber for the species has ever been found.
Termite facts and figures
- Termites are social insects which live in colonies and eat non-stop 24 hours a day.
- They are known as "silent destroyers" due to their ability to chew through a variety of substances, including wood, flooring and wallpaper.
- There are so many termites in the world that their combined weight is more than that of all the humans.
- Termites have wings that they shed once they have found a good place to build a nest.
- There are about 2,000 known termite species in the world.
- Each year termites cause more than £3.9 billion worth of property damage.