Researchers calculated that creatures large and small rival the landscape reshaping power of half a million major floods each year.
February 26, 2025
The little red and brown termite Syntermes dirus might be less than an inch long. But it can literally move mountains.
The Brazilian insect as the chief architect of earthen mounds as much as four meters tall that carpet a section of eastern Brazil the size of Virginia. There, 90 million mounds represent earth moving equal to 900 of Egypt’s Great Pyramid. Their discovery prompted scientists in 2015 to declare it “ the greatest example of insect … ecosystem engineering at a landscape scale.”
The termite is a dramatic illustration of how organisms besides humans can reshape the earth’s surface, much like forces such as wind and water. But it’s not the only one. And their collective capacity to literally move the Earth is greater than previously known.
“The role of animals in shaping Earth’s landscapes is much more significant than previously recognized,” said Gemma Harvey, a scientist at Queen Mary University of London who studies how organisms interact with the Earth’s surface.
Harvey led research that recently unveiled an eye-popping estimate for just how much wild animals are influencing the planet’s soil and rocks. By their calculations, every year it’s at least equivalent to hundreds of thousands of major floods that sweep rocks and sediment downstream. And that, they say, is a conservative number. “These estimates,” the authors write, “are astounding.”
It’s not just termites getting into the act. There are some of the best known and most charismatic examples: beavers that dam entire valleys; salmon that dredge river bottoms for their nests; grizzly bears that excavate hillsides in search of roots.
But that, it turns out, is just a tiny fraction of all the critters busily moving earth to and fro. Harvey and colleagues counted nearly 500 wild species and five domesticated livestock where scientists have documented their ability to influence the shape of the landscape, from the lowly ant to the African elephant. In many cases, they amplify erosion. Hippopotamus trails, for instance, can become the seed for networks of creeks. In others, such as the termites, they can collect soil together to build structures. In many cases, it’s as simple as a creature such as a tortoise digging an underground burrow, which then paves the way for mice and crickets to add their little burrows to the maze. Don’t forget the roughly 20 quadrillion ants, many moving one grain of soil at a time. Add them all up, and it can become a subtle, planet-spanning, never-ending earthquake.
Adding them up is what Harvey and company did. The scientists tracked down studies for all the land and freshwater organisms whose earth-shaping powers had been measured. Then they used estimates of the global biomass of different types of animals, and factors such as the abundance of earth-moving species within those groups, to calculate the total biomass of the earth shapers (my terms, not theirs). They converted this biomass into calories to come up with their total energy content. Then the scientists made what they considered a conservative estimate that 1% of the organisms’ total energy was spent somehow influencing earth movement. They emerged from this mathematical thicket with the following pronouncement: These wild animals expend roughly 76,000 gigajoules per year shaping the Earth, the equivalent of more than half a million major river floods, a much more widely recognized force carving away at the Earth. “From beavers creating wetlands to ants building mounds of soil, these diverse natural processes are crucial, yet we risk losing them as biodiversity declines,” said Harvey.
And that’s just a fraction of the overall picture. By Harvey’s estimates, the effect of livestock – all those cows, goats, sheep and other hoofed creatures – dwarf the wild animals. Their land-moving power is roughly 450 times greater – 34.5 million gigajoules.
Then there are humans. The paper’s authors don’t calculate that. But when you add up our own biomass, plus all the energy we extract from the planet to drive bulldozers and other earth-moving machines, well … how big do you think that number is?
Harvey, et. al. “Global diversity and energy of animals shaping the Earth’s surface.” Proceedings of the National Academy of Sciences. Feb. 18, 2025.
Image: by ayeshafernando/Envato Elements
[For comparison: according to the graphic below, the energy related to human activity in 2023 was 619 exajoules. That means 619.000.000.000 gigajoules. The energy used in human activity is, therefore, around 10 million times higher than what is mentioned in the article. RT]
Uma (in)certa antropologia 
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