If you’re scared of spiders, don’t read this post.
Seriously, don’t read this.
The great evolutionary biologist J. B. S. Haldane once wrote of “our Creator” that he “would appear as endowed with a passion ... for beetles ... for the simple reason that there are nearly 300,000 species of beetle known ... as compared with somewhat less than 9,000 species of birds and a little over 10,000 species of mammals.”
Well, God may like beetles, he also has an inordinate fondness for spiders, for there are very, very many of them.
A pair of biological researchers, Martin Nyffeler at the University of Basel in Switzerland and Klaus Birkhofer of Lund University in Sweden, recently published some fascinating findings involving the biomass of spiders in The Science of Nature earlier this month.
If you were to add up all the spiders in the world, they would collectively weigh 29 million tons. Nyffeler and Birkhofer attempted to measure the amount of food spiders consume in a given year. As you know, spiders subsist largely on insects, but it does happen sometimes that spiders eat lizards, birds, and even small mammals.
According to the two biologists, all of the spiders on the earth consume somewhere between 400 million and 800 million tons of prey in any 12-month period. Just in case you’re insufficiently impressed by the big numbers being thrown around, the quantity of meat and fish that humans consume every year is around 400 million tons. Therefore, it’s quite possible that the world’s spiders are eating more animal biomass than humans are.
It gets worse.
How much do you think that all human biomass weighs? According to estimates, the total weight of all human adults is 287 million tons, and even if you add in all of the children in the world, you still don’t reach 400 million tons, which is the low end of the estimate for how much spiders eat in a year.
Is there a spider in your house? Is he watching you? If so, what is he thinking about?
If spiders ever get their act together, we’re fuuuucked.