By Norman Knight
According to an article published in The Science of Nature, researchers at the University of Basel in Switzerland have determined that spiders eat somewhere between 440 to 880 million tons of insects a year.
In an attempt to offer some helpful perspective, the story reports that this is equal to the weight of 85 million elephants. To be honest, that doesn’t really help me because I can’t picture 85 million elephants any more than I can imagine 880 million tons of insects. Still, that seems like a lot of insects. And elephants.
To further attempt to clarify the size of the arachnid appetite, the news item explains that whales ingest up to 550 million tons of fish and other seafood while seabirds around the world snack on 77 million tons of fish.
So why is it that we say someone who really likes to eat has a whale of an appetite while a finicky eater who barely picks at the plate eats like a bird?
The comparison-making continues by informing us that humans gobble up to 440 million tons of meat and fish a year. I assume this number includes people who visit all-you-can-eat buffet restaurants, church pitch-in dinner participants and teenage boys. It is not clear to me, though, how vegetarians figure into the food tonnage estimates.
Even so, vegetarians along with pescatarians and carnivores might want to offer up a big “thank you” to spiders all around the world.
And they are, in fact, all around the world, says Martin Nyffeler, one of the authors of the study. The adaptable spider can be found on islands in the Arctic Circle, in arid deserts, and at the highest altitudes—any habitat where life can survive.
Spiders deserve our gratitude because they eat insects. Millions of tons of them as we have learned from the research. That’s a good thing because insects cause humans tons of problems.
Spiders aren’t too discriminatory when it comes to types of insects they will eat, but we can be thankful that among their dinner choices are pests that are harmful to humans and our food supply. Just imagine what the world would be like with 800 million tons more hungry beetles in your garden and annoying gnats swarming around your head. Spiders are natural insecticides.
As it is nature’s tendency to find a balance, spiders are not only predators but a food source for other predators, as well. In addition, they comprise an important part of the diet of 3,000 to 5,000 different species of birds.
But instead of reaping our most profuse gratitude, spiders bear the brunt of our fear and revulsion. For most people, the default setting when spotting a spider is to either scream and run away or find a newspaper and start swatting. (I’m talking to you, Garfield.)
We have a special psychological category of fear, arachnophobia, to describe our horror of these eight-legged creatures. True, a few are poisonous enough to be deadly, so maybe it’s not surprising that spiders are not among our favorite animals.
Some scientists argue that we developed this fear early in our evolutionary past while others insist that it is a learned, cultural behavior. Whatever. The fact remains that spiders are overall a good thing for humans to have around.
As Nyffeler states in his article, he hopes his work will increase appreciation of the “important global role of spiders in terrestrial food webs.” I am not sure if he meant that to be a pun, but it’s a pretty good one.
Oh, and as long as we are tossing around tonnage, there are approximately 25 million tons — that’s tons — of spiders currently crawling around on our planet. Sleep well.
Norman Knight, a retired Clark-Pleasant Middle School teacher, writes this weekly column for the Daily Journal. Send comments to [email protected].
