Why humans fear snakes and why that matters for science and conservation

Stephen S. Hall’s Slither explores our ancient aversion to snakes and the surprising scientific promise they hold.

Illustration by Hannah Stouffer

By Anna Fadiah and Hayu Andini

I don’t love snakes. In fact, I never have. During my college years, I lived in a rundown loft in lower Manhattan with my sister Lisa, who studied dance at Juilliard and adored animals. That apartment became a sanctuary for all sorts of unconventional pets. We had fire toads that thrived on crickets—crickets that often escaped their enclosures and invaded our kitchen. We had two rescue parrots, Begin and Arafat, clever and charismatic but afflicted by compulsive feather-plucking, who would free themselves from their cage and perch on overhead heating pipes, leaving droppings in their wake.

And then there was Lovey, a four-foot-long reticulated python. Unlike Lisa, who would calmly bathe with Lovey coiled around her shoulders, I found the snake absolutely terrifying. After feeding, he seemed to grow in both strength and size, pushing off the heavy textbooks we’d stacked atop his vivarium and slithering up pipes, often in pursuit of our shrieking parrots. It wasn’t just that he was strong or fast—it was that he seemed alien. That unsettling quality explains a lot about why humans fear snakes, even in modern urban environments where snake encounters are rare.

The deep roots of snake fear

Stephen S. Hall addresses this ancient and instinctive discomfort in Slither, his engaging and often surprising book about the science of snakes. Early in the text, Hall asserts that humans are biologically hardwired to fear snakes. Evolutionary biologists have proposed that our high-functioning visual systems evolved specifically to detect serpentine shapes in grass or foliage, an ability that likely saved early humans from venomous bites. In other words, fear of snakes helped our ancestors survive.

That deeply rooted fear has been reinforced through centuries of cultural influence. From the serpent in the Garden of Eden to the exceptional clause in the Talmud allowing Jews to kill snakes on the Sabbath, snakes have often been cast as symbols of danger or evil. Contemporary media doesn’t help. Stories like the New York Post’s headline “Subway-Riding Snake Freaks Out New Yorkers” tap into and amplify our long-standing fear of serpents.

The costs of fear

But why humans fear snakes is only part of the story. Hall argues that our aversion to snakes carries real consequences—for the animals, for the environment, and even for science. On the positive side, fear keeps people from approaching or handling dangerous animals. On the negative side, it fuels actions like intentional harm to snakes. Hall cites research showing that many drivers, if given the chance, will deliberately run over a snake on the road—what he calls “anti-reptile road rage.”

This aversion also hampers conservation efforts. Many snake species are endangered or threatened, yet efforts to protect them face an uphill battle because public sentiment is so hostile. Worse still, this fear might be slowing scientific progress. As Hall makes clear, snakes offer a trove of biomedical and technological insights. But funding and public interest can be hard to come by when the subject inspires dread instead of curiosity.

What snakes can teach us

Hall’s book is full of revelations about what makes snakes unique—and why that uniqueness matters. For instance, after a large meal, snakes’ internal organs grow dramatically to aid digestion, only to shrink again afterward. This rapid organ growth and regression mimics cancer cell behavior but in a controlled, reversible form. Understanding this process could reshape how we study cancer, diabetes, and tissue regeneration.

Snake movement is another area with broad implications. Hall describes snakes as “all-terrain vehicles” capable of navigating complex environments in ways that could inspire the next generation of robots. These snake-inspired machines could one day explore disaster zones, slipping through rubble or collapsing structures in search of survivors.

Even snake reproduction is full of fascinating adaptations. Female snakes engage in postcopulatory sexual selection—a biological process in which they decide, after mating, whether or not to retain the male’s sperm. This gives researchers a window into complex reproductive strategies rarely seen elsewhere in the animal kingdom.

Snakes as sensory specialists

Another striking aspect of snake biology is their sensory system. A snake’s flicking tongue is more than just dramatic—it’s a precise instrument for “tasting” the air. Through chemosensory detection, snakes can identify prey, predators, and potential mates. Hall describes how some species can follow scent trails back to their dens after months away, guided by trace molecules alone.

Then there’s the astonishing capability of snakes to consume meals larger than themselves. Hall recounts how some species can dislocate their jaws and stretch their bodies to swallow prey twice their size—imagine a 137-pound human downing a 220-pound dinner in a single gulp. This feat involves a remarkable rearrangement of muscle, bone, and skin, a biological marvel that continues to fascinate scientists.

Evolution in real time

Invasive python populations in Florida offer a real-time example of snake evolution. After arriving in the late 20th century, pythons have multiplied rapidly. A cold snap in 2010 killed many, but survivors passed on genes that improved cold resistance. As a result, these snakes have expanded northward and may one day be spotted as far north as Washington, D.C. This adaptive success story underscores how quickly snake populations can evolve in response to environmental pressures.

Venom, pain, and potential

No book about snakes would be complete without a thorough look at venom, and Hall doesn’t disappoint. He explains that technically all snakes are venomous, though not all are dangerous to humans. Of the 600 known venomous species deemed medically significant, each has a venom composition tailored to its ecological niche.

Some rattlesnakes, for example, use a fast-acting neurotoxin to immediately immobilize prey like kangaroo rats, ensuring they don’t escape before the venom takes full effect. Hall presents venom as “intrinsically ecological”—a tool shaped by habitat, prey behavior, and evolutionary history. Understanding how different venoms work could unlock new treatments for pain, infection, and even cancer.

A compelling, accessible read

Hall is no stranger to science writing. With previous titles like A Commotion in the Blood, he’s earned a reputation for turning complex subjects into compelling narratives. Slither continues that tradition. His writing is rich in metaphor, full of humor, and effortlessly readable. Even the densest sections, such as those on genetics, are clear and engaging.

His anecdotes—from scientists “slithering into hyperbole” to people who “basically committed suicide by snake”—stick with the reader, illustrating the human fascination with and revulsion toward snakes. By weaving personal stories with scientific research, Hall has created a book that might even change how we feel about snakes.

Changing minds, one snake at a time

In the end, Slither is about more than just reptiles. It’s about human perception, fear, and the blind spots that come with them. Hall makes a convincing case that our instinctive fear of snakes may be outdated and counterproductive. By understanding why humans fear snakes, we open the door to appreciating what these remarkable animals can teach us—and perhaps even to protecting them more effectively.

For those willing to confront their phobia, Slither offers a chance not just to learn, but to evolve. And that’s something both snakes and humans do best.