Arachnophobia, or the fear of spiders, is usually listed as one of most common fears that afflict humans. And if you are among those that suffer from it, then this fact may just creep you out even more (otherwise, beyond its scientific value, it is simply fascinating): spiders around the world eat more food by weight every year than all the meat and fish consumed by all humans put together, killing between 400 million and 800 million tons of insects annually.

Martin Nyffeler, an expert on the ecological impact of spider predation, from the University of Basel, Switzerland, put forth the figures in a new paper published Tuesday in the Science for Nature journal. Over 45,000 species of the eight-legged creatures have already been identified and while it is impossible to ascertain the exact number of individuals, they are estimated to weigh about 25 million tons in total biomass, he said. Which means that weight for weight, the arachnid group as a whole consumes 16-32 times its biomass every year.

Depending on the habitat — and spiders occupy almost every known habitat except air and the seas — spiders can have densities of up to 1,000 individuals every square meter, but the overall global mean average is thought to be about 130 individuals. Spiders that live in forests and grasslands are responsible for over 95 percent of the total prey kill for their species, while those living on farmland are thought to contribute less than 2 percent of annual global prey kill, the paper said.

Read: Boy Survives Poisonous Spider Bite

Titled “An estimated 400–800 million tons of prey are annually killed by the global spider community,” it also specifies that “prey items that are killed in webs but remain uneaten are considered prey as well” for the study. The paper also makes the assumption that spiders actually eat about 80 percent of the biomass of prey they kill.

For some more context, all whales in the world’s oceans are estimated to kill prey in the range of 280-500 million tons a year, while all of the planet’s seabirds consume about 70 million tons of prey annually.

Spiders mostly eat insects, but have been known to sometimes eat plants too, usually to supplement their diets. Some larger species also eat lizards and small birds, and some spiders also prey on other spiders. Except Antarctica, they are found in every continent. The arachnid class emerged about 400 million years ago, during the Devonian period, but true spiders emerged only about 320 million years ago.

“We suggest that the predation impact of spider communities is particularly high in forest and grassland biomes, with considerably lower impact in desert, urban, and tundra biomes. These estimates emphasize the important role that spider predation plays in semi-natural and natural habitats, as many economically important pests and disease vectors breed in those forest and grassland biomes,” the study concludes.

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