Turns out spiders could eat every human in one year, if they felt like it
A recent study confirms stats that put your worst spider nightmares to shame.
Spiders, like all predators, are mercilessly voracious: eat first, ask questions later. It's on their crest, in Latin. This intelligence we already had. But now their voracity has been measured under scrutinous scientific study, and quantifying their appetite has officially upped the ick factor of Earth's least popular creepy crawly – which is saying something.
A recent study published in The Science of Nature confirms some scary stats. The spiders of Earth match us pound for pound in consumed flesh. Yes, for every ton of meat we eat annually, they eat at least as much, or double. Martin Nyffler and Klaus Birkhoffer have scientifically calculated that spiders toss back between 400 million and 800 million tons of prey in any given year. Nyffler and Birkhofer are careful to specify that's in "fresh weight" by the way, so, still alive and kicking. You and I, and the other 7 billion of us, only match that appetite on the low end at about 400 million tons of consumed meat and fish per annum.
Their insatiability as feeders is impressive – but the needle on the creep-o-meter almost breaks off when you recognize that we, too, qualify as comestible food stuffs in all four eyes of many arachnids. The typical spider diet is made up of bugs like millipedes, woodlice, flies, and yes, even their own family members. Bigger arachnids feast in style on lizards, frogs and birds. Occasionally, even plants make the menu, although veganism has been a hard sell in the spider community. Thankfully here, size matters, so we're "safe". Still, the total biomass of all humans, young and old, has been estimated at about 350 million tons of "meat", so, theoretically, if spiders got their act together they could dine on the human race and still have plenty of room for seconds as they picked their teeth.
If, like me, you're still clinging to the faint hope that studies can be skewed and all data is potentially biased, note the methodical way Nyffler and Birkhoffer got their numbers. They relied on existing scientific evidence for the amount of spiders living in a square meter of hospitable land on Earth, and the average amount of food consumed by spiders of various sizes in a given year. Fair warning: this data will be inconvenient for any arachnophobes out there....
Canadian arachnologist, A.L. "Bert" Turnbull, who is quoted in the study, calculated "an overall mean density of 131 spiders m2 based on assessments from many different areas of the globe" back in 1973. Imagine standing in a square meter with no less than 131 spiders (that's 1,048 legs if you like math). If that seems high, consider Turnbull's research: "…Spiders exist in the most northern islands of the Arctic, the hottest and most arid of deserts, at the highest altitudes of any living organisms, in the depths of caves, in the intertidal zone of ocean shores, in bogs and ponds, on high, arid moorlands, sand dunes, and floodplains". They. Are. Everywhere. In fact, another estimate, places the average "peak density" at about 1,000 spiders per square meter under "favorable conditions". Barf. I just cringed so hard I dislocated something. (Kindly take a beat while I rock myself and mumble the following: only in rainforests, only rainforests, only rainforests. I'm back. Barely.) I've never been happier to be Canadian – although we did get a cuddly new jumping spider recently.
For some parting nightmare fuel provided by the study, note that the Earth's total spider population weighs about 29 million tons. Or 478 Titanics (52,000 tons per "unsinkable ship"). If you want to figure out how many spiders that is, the very largest spiders weigh about 85 grams, so convert to pounds (.00204), then divide that into 2,000 to account for spiders per ton... then multiply by 52,000, then 478... and then forget about ever finding inner peace. Thanks, science! Chapeau, Nyffler and Birkhoffer, your work is done. Oh, and chapeau, spiders. Rest easy in the dark corners of the planet knowing you're in no danger of losing your title as the number one phobia among humans. Among flies too, I'm guessing.
Off you go to scan ceiling corners.
Marc Beaulieu is a writer, producer and host of the live Q&A show guyQ LIVE @AskMen.