Cats vs. Dogs: which is the better pet?

Science settles the debate

It is time to settle the debate once and for all: Which is the better pet, cats or dogs? I believe there is unbiased answer to this question rooted in science, and I am honored to accept the role of impartial judge. I will provide a verdict based on the best scientific evidence that speaks to the pros and cons of pet ownership. To settle the debate, I will break the “best pet” question into five categories:

1)      The pet that makes people the happiest

2)      The pet that is more dangerous to humans

3)      The pet that is better for the environment

4)      The pet that is easiest to care for

5)      The pet that provides the most benefit to the world outside of being a pet

For each of these categories, I will comb through the scientific literature to figure out which species—cats (Felis catus) or dogs (Canis familiaris)—comes out on top.

The pet that makes people the happiest

People who own a pet generally consider their lives improved by pet ownership. In a survey of Croatian pet owners, over half considered their cat or dog the most important member of their family. More important than their spouse, parent, or child! Another study found that spending $5 on treats or toys for a pet made people happier than if they spent that $5 on themselves or a loved one. Evidence directly comparing pet-owners to non-pet owners found that owning a pet generally makes people more satisfied with life, although not always happier. In fact, pet owners are probably less happy than non-pet owners despite believing that their pets make them happy – a phenomenon termed the pet-effect paradox.  

So if you do own a pet, which one will make you happier; a cat or a dog? One study from Mexico directly comparing cats to dogs found that people report “greater emotional closeness with their dogs than with their cats, indicating that people perceived greater social support, companionship, and unconditional love with their dogs.” Cats, however, were considered “less expensive, required less responsibility, and involved less restrictions,” leading the authors to conclude that pet-owners’ relationships with cats was better overall. 

But a “better” relationship based on it being “less expensive” does not always mean a happier relationship. Based on monthly expenses, my relationship with my office chair is “better” than with my daughter (who requires both food and a cellphone), but my office chair doesn’t make me happy like my daughter does. There was just one study that looked specifically at “happiness” (which they termed “wellbeing”) and found that, after controlling for the personality traits and baseline happiness levels of the owners, “dog owners had higher wellbeing.” In other words, no matter who you are and what your personality is like you will, on average, be happier owning a dog than a cat. The science suggests that dogs make people happier than cats, which gives them the win for this category.

The pet that is more dangerous to humans

There are many ways in which our pets contribute both negatively and positively to our physical health.  On the positive side, owning a dog means spending far more time outdoors walking than for cat owners. Dog owners spend 300 minutes each week walking their dog – that’s 200 more minutes than non-dog owners. On the negative side, all those walks lead to a huge number of injuries. In the US, close to 87,000 people visit the emergency room each year after tripping over their pets, with people being 7.5 times more likely to get injured tripping over their dog than their cat. Over a fifth of injuries were caused by dogs pushing or pulling their owners while out for walks. So while walking your dog is generally good for your health, it’s a somewhat dangerous activity.

Then you have diseases and infections, including rabies (more common in dogs) and the protozoan parasite Toxoplasma gondii, which humans can accidentally ingest after handling cat feces. Rabies is quite deadly with tens of thousands of people (mostly children) dying each year of the disease, and 99% of rabies deaths being directly attributed to coming in contact with a rabies-infected dog. Toxoplasmosis infections are common with almost 50% of the world’s population currently infected. It is rarely deadly, however, although it is quite dangerous to the unborn fetus and immunocompromised people.

The biggest impact on human health, however, comes from dog attacks. In the US, an average of 4.5 million dog bites are recorded each year. This results in over 300,000 visits to the ER, and about 35 deaths per year. Pet related injuries – most of them coming from dog attacks – were found in one study to be equally as dangerous to human health as smoking, drinking too much alcohol, consuming illegal drugs, or obesity.

While there are plenty of injuries caused by tripping over your cat and the occasional cat scratch, it is quite clear that dogs are the pet that is the most dangerous to human health. Which makes cats the winner for this category.

The pet that is better for the environment

There are serious environmental impact to growing the food we need to feed our pets. Around 56–151 million tons of CO2 is released each year in pet-food production – that’s about 3% of global agricultural emissions. This huge impact can be blamed on the meat needed to create both the dry and wet food that we serve our pets. Because of the relatively higher concentration of meat in dog food, it turns out that dogs are worse for the environment than cats with a study concluding that “dog food emissions intensity was 1.6 times that of cat food.”

But when it comes to environmental destruction, cats are the ones to look out for. Unlike dogs, cats (both feral cats and the indoor cats that we let roam outside of the house) are persistent and continuous hunters of local wildlife. In the United States, cats have been found to be “the single greatest source of anthropogenic mortality for US birds and mammals.” So all of the hunting that humans do, as well as the destruction of wildlife habitat pales in comparison to the carnage heaped on wildlife by domestic cats. According to the study, “free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually.” On top of that, up to 871 million reptiles and 320 million amphibians are killed by cats in the US each year. Cats are responsible for 14% of the recorded mammal, bird, and reptile extinctions according to the International Union for Conservation of Nature (IUCN) Red List.

There real is no competition in this category – dogs are by far the clear winner when it comes to which species is better for the environment.

The pet that is easiest to care for

This is the most subjective of the five categories. It’s difficult to define “ease” in this sense. But I take it to mean the pet that requires the least amount of energy and time to keep happy/healthy/alive.

In terms of the energy input required to feed your pet, cats and dogs are equal. Pet food is readily available in supermarkets. Feeding either species is as simple as opening a container and slopping its contents into a bowl. Either pet can be fed at time intervals of the owner’s choosing or given constant, on-demand access to a bowl of dry food.

It's what happens to food once it arrives at the other end of your pet that matters for this discussion. Dogs need to be let outside to both poop and pee. That requires substantial energy expenditure on the part of the owner. And this is on top of the regular walks that most dogs need just to stay sane. Yes, these constant walks are good for human health, but they certainly aren’t “easy” (and can be dangerous, as we’ve seen). A cat, on the other hand, poops in a box. It’s a magically stress-free system that requires minimal effort to deal with. Emptying the litter box once a week is all it takes. That’s thirty minutes of work per week, as opposed to the 300 minutes of outdoor excursions that dogs require.

And then you have the famous aloofness of cats, which makes them easier to deal with. The average cat does not require as much attention or affection as the average dog. Which means you can leave a cat alone for hours at a time without any negative emotional consequences to either your or your cat, and less of a risk of your cat destroying your couch because of “separation anxiety”. Dogs require more social contact—often physical—than cats. As fun as social contact can be, it’s certainly less easy to fulfill a dog’s social need than that of a cat.

Dogs simply take more physical and emotional work as an owner than cats. Final verdict: cats are the victor when it comes to ease of care.  

The pet that provides the most benefit to the world aside from being a pet

That’s two victories for cats, and two for dogs, which means that this final category is the one that will settle the debate.

Modern housecats descended from a Middle Eastern wildcat that was domesticated about 12,000 years ago. The cat-human relationship began when farmers in the ancient Fertile Crescent began growing and storing grain. The grain attracted mice which in turn attracted wild cats. These cats were soon tamed and tagged along as humans spread across Europe. They were not, however, cute and cuddly lap cats living along side us in our homes, but instead kept outdoors (in barns and on ships) and used almost exclusively to control rodent populations. It wasn’t until the 19th century that cats were brought into our homes. Cats, then, were integral to human civilization because of their hunting skills. Without them, our ability to farm and store grain for the winter would’ve made it difficult to grow our population.

Dogs play an even greater and more ancient role in the success of humanity. Dogs were first domesticated around 23,000 years ago from their ancient wolf ancestors in Siberia. They too helped us humans feed ourselves – long before humans even invented agriculture. They assisted us with hunting, and protected their human friends from predators. Humans and dogs have been helping each other since the last ice age, and there is no doubt that the success of our species rests partly on the backs of our canine companions.

But unlike cats, dogs have taken on a huge array of non-pet related roles in the modern age. There are service dogs that assist people with visual impairments, mobility issues, and hearing loss navigate the environment. There are dogs trained to help recognize and warn when someone is having a seizure, and can provide assistance and companionship during the seizure itself. There are dogs used in the military and in police forces around the globe, doing everything from sniffing out bombs or contraband to tracking down and confronting criminals. There are search and rescue dogs that find people lost in the woods or buried under the snow after an avalanche. There are therapy dogs that provide emotional support to people at home, in hospitals, or in nursing homes. And we still use dogs for hunting and farming  - from the breeds that herd farm animals to the breeds that flush out and retrieve prey, find truffles, and even hunt for lobsters. Dogs can even be trained to track whales by smelling their poop floating on the surface of the ocean, locate spoiled wine in a wine cellar, and sniff out cancerous tissue or Alzheimer's disease in a patient’s urine. Unlike cats, dogs help humans with a seemingly endless list of non-pet related problems. Which gives them the leg up in this category.

The Conclusion

With a slim majority of 3 to 2, the final answer to the age-old question of which is the better pet is: dogs.

A quick message to the cat lovers out there: Listen, I am a cat guy. We’re on the same team. I personally feel that cats make better pets. Dogs are smelly and needy and altogether too in-your-face. But those are just my personal feelings based on my own pet preferences. Each of us has our own pet needs and thus on an individual level, cats are better for some people than dogs. But I cannot deny that when you objectively analyze pet ownership as a whole—across all societies and throughout history—dogs come out on top.

Maybe you—my fellow cat evangelist—disagree with the way I went about the analysis. Maybe you object to the (admittedly arbitrary) five categories I used for evaluation. That’s a perfectly cromulent complaint. Perhaps if I added another category—like pet with the most prominent butthole or pet with the cutest toe-beans—cats would’ve won. But I swear to you that I chose the 5 categories from a place of total objectivity, hoping that they reflect the benefits/pitfalls of pet ownership. And to be honest, I was expecting cats would win. So I even surprised and disappointed myself with these results.

And this I feel is a good lesson for the turbulent times we live in. If the evidence does not match up with your long-held beliefs, it’s OK to follow the evidence first and your heart second. So I will follow the evidence in declaring dogs the better pet. Enjoy your victory dog people. On paper, you win. But in my heart, cats are still number one.