When it comes to eating meat, spiders do their share—and then some. Zoologists at the University of Basel in Switzerland and Lund University in Sweden report in the journal the Science of Nature that, according to their calculations, spiders kill between 400 million and 800 million tons of prey every year. The planet's 7.5 billion humans, by comparison, consume 400 million tons of meat and fish a year, per the UN's Food and Agriculture Organization, while the prey kill of whales is 500 million tons at most, reports New Scientist. Seabirds pick off a relatively paltry 70 million tons.
Spiders may be small and light, but there are 45,000 different species of them that can reach population densities of 1,000 per square meter, per Phys.org, and taken together, they weigh roughly 25 million tons. (That's right, they far out-eat their own weight. Humans' animal consumption is closer to that of our own weight, which per a 2012 study cited by Live Science is 316 million tons.) And while spiders do eat some vertebrates, including small mammals, frogs, and birds, their primary role is as insect predator; 90% of their prey are either insects or springtails, which are insect-like arthropods. Per the study, the researchers hope to "raise public awareness and increase the level of appreciation for the important global role of spiders in terrestrial food webs." (Yes, this spider is carrying a mouse up a fridge.)