The Stuff of Nightmares: Spiders Could Eat All of Us in Under a Year…Theoretically

Arachnophobes, beware: This is the stuff of your worst nightmares.

Spiders are relentless, unrepentant killing machines. They mostly eat insects, but some *gulp* larger spiders munch on more sizable prey, including lizards, birds, small mammals…and even snakes (click here for horrifying images).

Two European biologists – curious about exactly how much prey the “global spider community” kills annually – did some research and came up with some unsettling numbers.

Reporter Christopher Ingraham was kind enough to bring this study to our attention. He reminds us that spiders are “quite literally all around us” and that there’s a good chance “at least one spider is staring at you right now, sizing you up from a darkened corner of the room, eight eyes glistening in the shadows.”

How very comforting, especially considering the tidbits of information he’s about to drop.

Ingraham goes on to summarize the study’s findings (emphasis mine):

Martin Nyffeler and Klaus Birkhofer published their estimate in the journal the Science of Nature earlier this month, and the number they arrived at is frankly shocking: The world’s spiders consume somewhere between 400 million and 800 million tons of prey in any given year. That means that spiders eat at least as much meat as all 7 billion humans on the planet combined, who the authors note consume about 400 million tons of meat and fish each year.

Or, for a slightly more disturbing comparison: The total biomass of all adult humans on Earth is estimated to be 287 million tons. Even if you tack on another 70 million-ish tons to account for the weight of kids, it’s still not equal to the total amount of food eaten by spiders in a given year, exceeding the total weight of humanity.

In other words, spiders could eat all of us and still be hungry.

Oh, but there’s more.

Spider biologists have also generally found that spiders consume approximately 10 percent of their body weight in food per day. That’s equivalent to a 200-pound man eating 20 pounds of meat each day.

Conversely, it would take approximately 2,000 pounds of spiders to consume a 200-pound man in one day.

Just how many spiders ARE out there?

…one study estimated that global average spider density stands at about 131 spiders per square meter.

And there’s this…

…spider densities of 1,000 or more individuals per square meter have been observed under certain ‘‘favorable’’ conditions.

“Favorable” is not defined.

Naturally, the good folks on Twitter are having some fun with this story…

Spiders are everywhere. And they could eat all of us in under a year. https://t.co/tInyuTs66H pic.twitter.com/D7RsxDTfFP

— The Boston Globe (@BostonGlobe) March 28, 2017

@BostonGlobe Thanks, I never wanted to sleep again anyway.

— Aaron Azimov (@AaronAzimov) March 28, 2017

@BostonGlobe @TheRickWilson We need to build a wall to keep the spiders out.

— Chris Stephens (@PureGuesswork) March 28, 2017

Spiders AREN’T more scared of us than we are of them. In fact they mock our lack of legs and how easy it is to gain access to our homes.

— GCS (@GCSRecruitment) March 28, 2017

Ingraham had a bit of fun with it himself…

You’d need about 2,000 pounds of spiders to fully devour a 200-pound man in one sitting #tuesdaythought https://t.co/26irzLxhGZ

— Christopher Ingraham (@_cingraham) March 28, 2017

@_cingraham hm I bet it would depend on the spider, ide say a couple Goliath’s or Giant Huntsman’s would probably devour us with no issues

— JIMI ANTWON (@JiMiAntwon) March 28, 2017

@_cingraham @washingtonpost This begs the obvious question: Would you want to be eaten by 1 200 lb. spider or 4 million 25 mg spiders?

— Brian DiNunno (@BDiNunno) March 28, 2017

Spiders. https://t.co/kOVGMVJfCp pic.twitter.com/Y7SVkk3UOe

— Christopher Ingraham (@_cingraham) March 28, 2017

Sure, spiders COULD eat all of us, but SHOULD they? Yes, yes they should.

— metal?txt (@metaltxt) March 28, 2017

rt if you’re rooting for the spiders https://t.co/qbK08ATTsK

— rae paoletta (@PAYOLETTER) March 28, 2017

And of course, because EVERYONE is on Twitter these days…

Would ya look at that humans?
We are famous! ::)⚡️ “Spiders could eat all the humans in a year and still be hungry”https://t.co/XrS4PzBntS

— Hi! We Are Spiders (@hiwearespiders) March 28, 2017

In other words,
DON’T PISS US OFF!
Muahahahaha. ::) https://t.co/un2bm8WpRK

— Hi! We Are Spiders (@hiwearespiders) March 28, 2017

You humans just don’t know how much We love you!! ::)
We’ll just, y’know. Be here.
Watching you nap on the break room couch. We see you. ;;) pic.twitter.com/vQKratMFfY

— Hi! We Are Spiders (@hiwearespiders) March 28, 2017

We love you, humans! ::) ::) ::)
…and yes, even other species. pic.twitter.com/wX3GPZrgk6

— Hi! We Are Spiders (@hiwearespiders) March 28, 2017

Of course, spiders are a beneficial part of the circle of life.

But it still might be best to sleep with one eye open.