Fantastic Beasts

“Spiders could theoretically eat every human on Earth in one year,” said a recent headline in The Washington Post. An infographic bearing the title, “The crushing weight of spiders” followed, explaining that the world’s spider population weighs 29 million tons — the equivalent of 478 Titanics. And, if you didn’t gather from the article’s lead, these 29 million tons of arachnids apparently have voracious appetites: “… spiders could eat all of us and still be hungry,” it went on to say.

Why do stories like this one draw so much attention? We all know that we’re not actually going to wake up one morning to see spiders feasting on our families and friends. Yet Americans love hearing sensational stories about insects, arachnids and rodents. We seem unable to resist sinking our own teeth into even theoretical horror stories featuring these intriguing creatures.

“We are fascinated by insects because they are so different from us anatomically that they seem like aliens,” says Dr. May Berenbaum, whose Insect Fear Film Festival has drawn swarms of curious thrill-seekers to the campus of the University of Illinois at Urbana-Champaign every year since 1984, and whose book “The Earwig’s Tail: A Modern Bestiary of Multi-legged Legends” lightheartedly debunks popular myths about insects. “Their hearts and nerve cords are on their belly side, not back side, and their skeletons are on the outside. Basically they are built inside out and backwards compared to us.”

Their life cycles are cause for amazement as well, adds Berenbaum, pointing to countless sci-fi writers who have borrowed from the insect world. “The infamous ‘chestburster’ scene in ‘Alien’ was based on the life cycle of a parasitic wasp,” she says. “We don’t have to make this stuff up because it actually happens. People can’t relate to some of these realities about insects, and so they have no empathy for them; they are instead horrified or, at best, mildly repelled.”

BUILT-IN FEAR. Fear heightens our senses; curiosity makes us look. Evolutionarily, we are wired to be acutely aware of the presence of animals with the potential to hurt us. In his 2013 book “The Infested Mind: Why Humans Fear, Loathe, and Love Insects,” Dr. Jeffrey A. Lockwood, a professor at the University of Wyoming, points out that emotions, thoughts and perceptions are shaped by the forces of natural selection just as anatomical traits are. “Evolution favors anxious genes,” he writes. “Our ancestors were better off to err on the side of caution. Mistaking a twisted stick for a snake, a tumbling leaf for a spider or a grass seed for a louse would have been better than ignoring these cues. A ‘false positive’ meant an unnecessary flinch or some pointless scratching, while a ‘false negative’ meant elimination from the gene pool.”

Societal norms and behaviors have taught us to feel certain ways about insects as well. Parents who scream at the sight of a bee or wasp are likely to instill fear in their children, for example. Of course, we can’t underestimate the effects of an actual sting either. “Once bitten, twice shy” isn’t just an adage; it’s reality to many who have developed a fear due to a traumatic episode.

Logically, we would think that these strong negative emotions would stop people from seeking out stories about insects and rodents. But this equation includes one more factor: our inherent curiosity.

Lockwood recounts a famous experiment conducted by Charles Darwin at the London Zoo. Aware of monkeys’ instinctive fear of snakes, Darwin placed a paper bag containing a live snake in the monkey house at the London Zoo. One monkey after another cautiously approached, opened the bag, peeked inside and darted off, horrified. Instead of trusting the negative reactions of their peers, they each felt compelled to take their own look.

And so evolution strikes again: We may never be invited to sneak a peek of a snake in a paper bag, but our neighbor’s gigantic garage spider is pretty darned tempting.

The author is a frequent contributor to PCT.