Every year, humans eat around 400 million tonnes of animal protein — roughly the weight of every living human (weird). Our stomachs are pretty big, but compared to the humble spider, that’s basically nothing. Recently, a team of Swiss and Swedish scientists calculated that globally, spiders eat up to 800 million tonnes of prey annually — primarily juicy insects but also frogs, lizards, fish and small mammals — twice as much as we eat.
Spiders can out-eat us, sure, but what about the biggest mouths on the planet, the whales? Yup. Whales eat somewhere between 280 million to 500 million tonnes of prey annually, so spiders consume 30 to 60 percent more than the largest creatures to ever live.
The arachnids’ incredible appetite is a good thing, though, because what we tell ourselves when we see a spider across the room but are too lazy to get up and do anything about it is true: They help keep the insect population in check.
“Our calculations let us quantify for the first time on a global scale that spiders are major natural enemies of insects,” Martin Nyffeler, from the University of Basel in Switzerland, told New Scientist. “In concert with other insectivorous animals such as ants and birds, they help to reduce the population densities of insects significantly. Spiders thus make an essential contribution to maintaining the ecological balance of nature.”
Ninety percent of a spider’s prey is made up of insects, meaning that annually, they devour up to 720 million tonnes of of them. Can you imagine a world with 720 million tonnes’ more insects each year? Thank you, spiders.