Nature vs. Nurture: Understanding the Roots of Dog Behavior

There’s an age-old debate that’s been discussed in science for decades, and it’s one that’s been circling in my mind lately as it relates to dogs: nature versus nurture.

When it comes to behavior, how much of what we see is written in a dog’s genetic code, and how much is shaped by experience and environment? More importantly — how much room do we actually have to influence that balance through training?

"It’s All in How You Raise Them”… Or Is It?

In the dog training world, we hear this phrase all the time:
“It’s all in how you raise them.”

But is that really true?

Over hundreds of years, humans have selectively bred dogs for specific purposes — herding, guarding, retrieving, companionship. Each choice reinforced particular drives, temperaments, and instincts. Those same traits, once crucial for survival or work, now show up in our modern pet dogs.

We didn’t just create physical differences between breeds — we shaped their minds. The Malinois that can’t stop scanning, the Border Collie that can’t help but stalk, the terrier that insists on chasing anything that moves — all of it is by design. These behaviors are part of what makes them who they are.

So when people say, “It’s all in how you raise them,” I can’t help but ask:
How much of that raising can truly override hundreds of years of purposeful breeding?

Nature and Nurture: A Partnership, Not a Battle

Every day, I work with dogs struggling with reactivity or aggression — toward people, dogs, or their environment. And almost always, I find myself asking:
Is this genetic? Learned? Or both?

The answer is nearly always both.

Genetics provide the foundation. Experience builds upon it. Over time, learned behaviors — especially emotionally charged ones — can amplify what’s already there. A slight predisposition toward reactivity can become a deeply ingrained habit when experience repeatedly confirms that emotional response.

It’s a feedback loop: nature creates potential, nurture shapes expression.

The Ethical Question: What’s Truly Kind?

This brings us to a hard but necessary question.

If reactivity results from nature compounded by nurture — each reaction reinforcing the next, creating a vicious cycle — what’s the most humane way to break that cycle?

Do we intervene quickly, using a balanced approach that incorporates both positive and negative consequences to bring clarity, stability, and relief?
Or do we take the purely positive route — avoiding all correction, managing triggers, and focusing exclusively on counter-conditioning, even if that means years of slow progress and a life of constant tension for the dog?

While the idea of “never using corrections” sounds appealing in theory, it often leaves the dog living in a state of chronic stress. Avoidance can only go so far; the world is unpredictable. Triggers will happen.

So we must ask ourselves:
Is it truly kinder to shield a dog from all challenge and maintain their stress for years — or to introduce short, controlled stress that builds resilience, predictability, and long-term peace?

Sometimes, what feels kind to us may not actually be kind to them.

The “Abused Dog” Assumption

I often hear people say, “My dog must have been abused,” when explaining difficult behavior.
And while that story can feel comforting — it gives a reason, a villain, something to fix — it’s rarely true.

In the vast majority of cases, genetics play a far larger role than we’d like to admit. That doesn’t mean environment doesn’t matter — it absolutely does — but it means we can’t ignore the biological blueprint beneath the surface.

As humans, we naturally seek reasons. We create stories to make sense of what we see. But sometimes, those stories distract us from the truth:
a dog’s behavior isn’t always about what happened to them — it’s about who they are.

Why Some Dogs Bounce Back… and Others Don’t

I’ve met dogs who’ve been attacked, yet remained socially stable and easygoing.
I’ve also met dogs who’ve never had a single negative experience and yet display extreme reactivity from puppyhood.

So what’s the difference?

Resilience. Genetics. Thresholds for stress — all built into the individual dog.

Two dogs can experience the same event and come away with completely different responses because their internal wiring — their nature — isn’t the same.

Finding the Balance

Maybe it’s time we stop arguing over which matters more and start focusing on how they work together.

Understanding a dog’s genetic predispositions allows us to tailor training to the individual — recognizing what’s realistic, what’s fair, and what will ultimately give that dog the best quality of life.

Because when we honor both who the dog is and what they’ve experienced, we can train with both empathy and effectiveness.

In the end, it’s never just about how you raise them.
It’s also who they were born to be.

Written by:
Maxime Gowans
Professional Dog Trainer & Behavior Consultant