A new study found that spiders consume an average of 400 to 800 million tons of insects every year. By doing this, the arachnids are holding the pest population under control while also keeping humanity protected from a large array of parasites of disease-carrying critters.
The Study Is Based on Specialized Literature
The study, entitled An estimated 400–800 million tons of prey are annually killed by the global spider community, published in The Science of Nature magazine looked at 65 values of spider biomass gathered from specialized literature.
Then, the team divided the values according to the arachnids’ biomes: temperate and boreal forests, tropical forests, temperature grasslands, tropical grasslands and savannahs, deserts, annual cropland, and Arctic tundra. All values were translated in fresh weight by also taking into account the average water content of a specimen’s body.
In order to determine how much food the spider community consumes yearly, the scientists used two different approaches. The first one was to multiply the estimated food requirements of a single specimen in a year with the total number of spiders on the planet. The second involved assessing the annual prey of specific spider biomes according to specialized literature.
Spiders Eat Twice as Much as Humans and Four Times as Much as Whales
According to the final results, the arachnids consume somewhere between 400 and 800 million metric tons of insects. By comparison, humans eat approximately 400 million tons of meat on an annual basis, while the whale population consumes roughly 280-500 million tons of food per year.
Over 95 percent of prey is captured by arachnids living in grasslands and forests while only two percent comes from crops. The researchers explained that “annual crop fields are disturbed habitats” where the spider population cannot grow enough to make a difference.
Apart from hexapods and insects, spiders also eat a large amount of other, smaller arachnids. This process is called “intraguild predation” and is seen more often in warmer areas where prey is scarcer.
A spider’s diet varies from disease-ridden insects to harmful parasites, other arachnids, and bees. They are both saving and condemning humanity by ridding it of parasitic and beneficial insects alike. However, one thing is certain, spiders may be considered the creepiest crawlers on the planet, but without them, the world would certainly look a lot different.
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