"What a luxury a cat is," wrote novelist and cat owner Doris Lessing in her triptych of essays on cats, "the moments of shocking and startling pleasure in a day, the feel of the beast, the soft sleekness under your palm, the warmth when you wake on a cold night."

"Cats know exactly where they begin and end," wrote Ursula Le Guin in her short essay on what cats can teach us about beauty—so much rich, mental substance devoted to these creatures.

The complexity of our love for pets has developed for more than 50,000 years—the date, archaeological evidence suggests, we first became fond of animals.

While our helpless love for animals is demonstrable, why we love them (not to mention why we invest, sacrifice, and finance them to the point of absurdity) is less clear.

How It Begins

A puppy is a puppy is a puppy.
He's probably in a basket with a bunch of other puppies.
Then he's a little older, and he's nothing but a bundle of longing.
He doesn't even understand it.
Then someone picks him up and says, "I want this one."

From Mary Oliver's Dog Songs

Illustration by Edward Lear.

Fortunately, the new science of anthrozoology sits at the intersection of psychology, sociology, neuroscience, and even biology. In this wonderfully researched and thoughtfully captured book, Animals Among Us, biologist John Bradshaw sets out to answer why pets?

Our thinking about animals has changed dramatically over the past century or so. Nowadays, we accord more kinds of animal 'rights' than ever. Over the past forty years, the idea has emerged, seemingly from nowhere, that having an animal in the home is part of a healthy lifestyle. We view pets as the antidote to the stresses of modern urban living, as a palliative for the loneliness that comes with the demise of the extended family.

How does evolution explain the belief that animals awaken our souls? Or a recent Gallop poll that found 44% of U.S. cat owners wouldn't part with their pet for less than 1 million dollars? We are helplessly devoted to pets. Indeed, the survivalists in us would select from these ridiculous habits to spend resources more wisely.

We might look at pet keeping as no more than an evolutionary accident that's never been selected out because, while we may indulge in it when we have surplus resources at our disposal, we can abandon the practice whenever it becomes a problem.

I will go further, however, and propose that it's been positively selected for because, in the past, it has afforded to those who happened to be good at it an advantage—or rather two advantages, each at a different stage of the evolution of our species.

In other words, we haven't devolved from our earliest needs of using animals for food and skins because no demonstrable harm outweighs the benefits. (For those grieving, the benefits of owning a pet can be transformative.)

"The Rum Tum Tugger is a curious cat." Edward Gorey's illustration for T. S. Eliot's Old Possum's Book of Practical Cats.

Only when something of a plague occurs (which is less likely in cats and dogs than, say, pigs, chimps, or even birds because we aren't susceptible to the same pathogens), owning certain pets hasn't been a problem, keeping rats, for example, just isn't done in most countries, without the Black Plague, would rats be more attractive?

Bradshaw further suggests we have actively selected for pet ownership: "People who were naturally good at taking care of animals left more descendants than those who excelled at hunting them."

Of course, the stereotype of the "crazy cat lady," a woman bereft of society except cats, contradicts this notion. There is something of our modern obsession with pets that exists outside evolution. If the book falls short, it is due to Bradshaw's inability to address this convincingly.

He tries: "Any health benefits that result from ownership of a dog we can plausibly ascribe to the relaxing effects of exposure to green spaces." But that doesn't explain why people who live in city apartments and walk their dog to the nearest cement-surrounded tree while remaining on their phone, only to return indoors, find this ownership worthwhile in the long run.

"The country is going to the dogs. But this has always been a nation of dog lovers. So why worry." George Mikes's How to Be a Brit.

Fido's personality does everything to make him extraordinary, but will the children of that family—if there are any—also want a dog? Although, evolution works in a cadence of millennia, not decades.

Luna. Photograph by Scott Danzig.

I think our modern obsession with pets addresses, first and foremost, our current loneliness and separateness from each other and nature.   An even stronger imagined relationship stems from the close bond we feel with animals. That we know them, understand them, and they us? Is that real? I believe it's the same expansion of ourselves up mythical steps as that which creates mythical beings in the first place—read Borges' Book of Imaginary Beings or a wonderful collection of Japanese folk creatures. Animals as pets are certainly much, but we make them more than they are. To mitigate loneliness? Which is not a humanity thing; it is a civilization thing.

Biologist Frans de Waal has worked with primates his entire career, and it makes a beautiful argument for our social natures;

Our bodies and minds are made for social life, and we become hopelessly depressed in its absence. This is why, next to death, solitary confinement is our worst punishment. Bonding is so good for us that the most reliable way to extend one’s life expectancy is to marry and stay married. The flip side is the risk we run after losing a partner. The death of a spouse often leads to despair and a reduced will to live, which explains car accidents, alcohol abuse, heart disease, and cancers that take the lives of those left behind. Mortality remains elevated for half a year following a spouse’s death.
From Frans de Waal's The Age of Empathy

There might be a time when we decide as a civilization that pet ownership outweighs the benefits. But let's not forget the animal's co-evolving to make themselves valuable and attractive. As those who have opened their souls to pets know, we might think we're in charge, but we're not.

Whatever happens, it will always be human to bond with animals deeply. As Douglas Adams wrote in Last Chance to See, his journey to discover critically endangered species like the Rwandan Mountain gorilla and New Zealand kakapo: “The world would be a poorer, darker, lonelier place without them.”