World's spiders devour 400-800m metric tons of insects yearly – experts

'We hope that these estimates and their significant magnitude raise public awareness and increase the level of appreciation for spiders,' study authors say

The world's spiders eat 400-800m tonnes of insects every year - as much meat and fish as humans consume over the same period, a study said Tuesday.

In the first analysis of its kind, researchers used data from 65 previous studies to estimate that a total of 25m metric tonnes of spiders exist on Earth.