When army ants are sweeping across the forest on one of their massive predatory raids, potholes tend to slow them down. And just the other day, British researchers revealed how these hard-charging creatures deal with the impediment: Individual ants fling themselves down and bridge the potholes with their bodies. In fact, the volunteers seem to size-match themselves to the holes they choose to plug. And when the army has tramped across their backs, they get up, dust themselves off, and head home to join the communal feast.

In other useless news, a researcher at the University of South Florida reports that the fastest tongue on Earth belongs to a giant palm salamander from Central America. The salamander fires its tongue like an arrow, using energy stored by stretching elastic fibers in its mouth. This is bad news for nearby insects.

But it’s wonderful news to me. Over the course of this month, I’m writing a series of columns about the quirky nature of behavior in both the human and animal worlds, and from time to time you will notice that the two worlds have a way of overlapping for me. The topics will range from my own hapless feelings of un-schadenfreude (see the first column in the series, which ran on Monday) to the idea of buying local as a remedy for global warming. The series is called “Basic Instincts” because I believe that what we think of as our highest human behaviors are often deeply rooted in animal biology.

I didn’t have any such idea in mind when I first started writing about behavior years ago. To be honest, I was just having fun. It seemed to me delightful to live in a world where, for instance, certain beetles have evolved to do handstands on the dunes of the Namib Desert, using their backs to catch and collect the precious mist drifting in off the Atlantic. (They actually have grooves on their backs to guide the water down to their mouths.)

The human beings who study such things often proved entertaining, too. I once spent time in the field with a brilliant researcher whose methods occasionally included humming to a spider (some spiders recognize their prey by sound). He also tended to pick up spiders with his fingers, commenting, for instance, that “when squeezed gently on the abdomen” one such spider “produced a strong, somewhat disagreeable odor reminiscent of … lampyrid beetles and canned string beans.”

I can’t quite place the smell. But I came to love the arcane details of animal behavior in part because they often seemed so splendidly useless. And useless knowledge is a precious thing. As a character in Tom Stoppard’s play “The Invention of Love” puts it, knowledge does not have to look good or sound good or even do good. It is good just by being knowledge. And the only thing that makes it knowledge is that it is true.” The character (based on the poet A.E. Housman) concedes that useful knowledge is fine, too, “but it’s for the fainthearted.”

Well, O.K., I sometimes also feel fainthearted. So I should add that useless knowledge often has an insidious way of leading people in useful directions. Charles Darwin, for instance, wasn’t looking for anything in particular when he collected finches in the Galapagos; it was years before it dawned on him that they were the key to understanding evolution by natural selection. And in recent decades, it’s been hard to miss how useless knowledge about the behavior of animals has begun to provide surprisingly useful insights into the behavior of human beings.

Not so long ago, science treated the two worlds as largely separate. Anthropomorphism — attributing human thoughts and feelings to animals — was a cardinal sin. This taboo was “anthropodenial,” according to the primatologist Frans de Waal, a way of preserving the special status of Homo sapiens. Over the past few decades, though, scientists have haltingly come to acknowledge that animals often respond to the world much as we do, and that we behave in many ways much like animals. Our behaviors aren’t separate. They’re just different points along a continuum.

And that realization has helped encourage what I think of as zoomorphism, the practice of using animal behaviors to explain what makes humans tick. A few years ago, for instance, researchers discovered that macaque monkeys have special neurons in their brains enabling one individual to mirror the actions of other monkeys. Useless knowledge. But scientists soon found that humans have mirror neurons, too, and they appear to be a key to understanding behaviors like empathy, emotional contagion and autism.

It can seem unsettling at first when distinctly human behaviors turn out to have a common heritage with that of other animals. Maybe that’s because of the misguided impression that the lives of animals are exclusively nasty, brutish and short. But zoomorphism just as often leads in the opposite direction. For instance, Frans de Waal was once watching chimpanzees when he noticed two male combatants resolve their hostilities with an embrace. In the old days of anthropodenial, scientists would have dismissed that “a post-conflict interaction.” But de Waal said it was a reconciliation. It was the beginning of the recognition that the way humans speak and respond to a phrase like “I’m sorry” isn’t just a social nicety. It’s a part of our deep biological heritage.

When it comes to behavior, whether on two, four, six or eight legs, I still love useless knowledge. But I’m no longer sure any such thing exists.