Spiders Are Top Predators, New Study Finds
(Photo : Ian Waldie/Getty Images)
Most people are already scared of these eight-legged creatures. Also, it seems that there are more reasons to fear spiders now more than ever. Biologists calculated that the global spider population consumes around 400 million to 800 million metric tons of insects every year.
Researchers noted that arachnid appetite means spiders consume the same amount as the weight of meat and fish eaten by humans each year. This revelation helped in putting a value on the spiders' ecological importance.
The findings were published in the journal The Science of Nature. In it, Dr. Martin Nyffeler of the University of Basel in Switzerland and lead scientist of the study mentioned that he was inspired by a book called The World of Spiders, which was published in 1959. Since then, he spent hundreds of hours studying spider behavior in the field.
These eight-legged hunters primarily feed on insects. But a few large spider species also eat worms and small vertebrates like birds, bats and even sometimes snakes.
After four decades of data gathering, he found that the entire arachnid population, which weighs around 25 million metric tons, hunts and eats somewhere between 400 million to 800 million metric tons of their prey every year. This is particularly important in understanding their contribution in the natural world.
"Spiders kill large numbers of herbivorous insects - and by doing so they help to protect the plants from herbivore damage," Dr. Nyffeler shared.
The number of spiders studied by Dr. Nyffeler and his team could give arachnophobes nightmares. Nonetheless, it is for an important cause.
"We hope that these estimates and their significant magnitude raise public awareness and increase the level of appreciation for the important global role of spiders in terrestrial food webs," he added in the research.
Live Science noted that spiders in particular are very successful as a collective species. They are everywhere, from desserts to grasslands, to rainforests and even in the Arctic tundra.
Their numbers are also as massive. Scientists believe there are around 45,000 individual species, and there are around 131 spiders per square meter of land on the globe. In some areas, there are up to 1,000 individuals.