When you look at your faithful pet, all waggy tail and eager eyes, it’s hard to fathom that, Dobermann or dachshund, Fido shares 99.9% of his DNA with a common ancestor, the grey wolf (Canis lupus).
Exactly when the domestic dog (Canis familiaris) became a distinct species is hotly debated, but, says James Serpell, emeritus professor in animal welfare at the University of Pennsylvania, “today’s dogs are a product of thousands of years of human selection for particular behavioural propensities and dispositions”.
These behavioural traits reflect the diverse roles we have asked dogs to perform over the course of our shared history, Serpell explains – from herding sheep to chasing hare and deer, killing vermin and guarding property and livestock.
Nowadays, many dog owners are more interested in their pooch playing nicely in the park, coming when they’re called and snuggling up on the sofa than hunting and herding. But is that fair? To what extent can dogs be expected to escape their genetic propensities?
Is a dog's breed and behaviour linked?
“The causes of behaviour are very complex,” says Zazie Todd PhD, an animal behaviour expert and author of Bark: The Science of Helping your Fearful, Anxious or Reactive Dog. “In the past, we used to talk about nature versus nurture, but these days, we know that’s an outdated approach. It’s not true to say ‘it’s all in the genes’ or ‘it’s all in how you raise them’ – the two are intertwined.”
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The problem with Morris
Let me introduce you to Morris, the Canis familiaris that graces my couch each evening. He is a pint-sized Jack Russell-fox terrier cross – a white-and-ginger streak of energy, with dark brown eyes fringed by ridiculously long lashes. “Terriers originated as hunting dogs,” Todd tells me. “They were used to control rats, mice, rabbits and foxes, so we can expect them to have a lot of energy, stamina, intelligence and tenacity.”
That sounds about right. Morris greets us in the mornings with wild licks; he lines his toys up across the floor when he wants to play; he will happily sit, perform a 360° spin or offer his paw for a biscuit. We love him to bits. But there’s a problem.
Morris is an escapologist. Only last week, he managed to get out of the garden and was missing for three hours. I say ‘missing’, but the problem isn’t finding him – I got within a few metres of him on two occasions – it’s getting him to come back.
“Morris!” I call in a sing-song voice, brandishing a piece of cheese. But I know from previous experience that once he is out, no amount of love, admonishment, cheese, or frankly, fillet steak, will lure him back. He glances up briefly, then continues his nose-led zigzag exploration of the field, as if he barely knows me.
Other terrier owners have sympathised over the years, telling us that theirs, too, have a stubborn streak – or selective hearing – when it comes to doing what they’re told. If such behaviour is ‘written’ in the genes of these energetic, feisty dogs, can training really help?
“Genetics is about inherited traits,” explains Todd. “Like humans, puppies inherit genes from their mother and father. Genes are made of DNA and carry a lot of information – we can think of them as being like a recipe book to make a human or a puppy.”
Does a dog's DNA affect its behaviour and personality?
While dogs share most of their DNA with each other – and wolves – small differences in the gene pool affect traits such as height, size, fur colour and type, as well as personality and behaviour. “Behavioural traits are determined by a larger number of genes than physical characteristics,” says Dr Joanna Ilska, genetics research manager for The Kennel Club. “That means there is more likely to be variation between individual dogs.”
In 2022, researchers at the Dog Genome Project (part of the USA’s National Human Genome Research Institute in Maryland) mapped the genome (the complete set of DNA) of more than 4,000 dogs. They found genes could predict the presence of specific behavioural traits among breeds with shared historical working roles.
What’s more, from the hundreds of breeds studied, they identified 10 distinct lineages (breed groups), which, when combined with owner-supplied behavioural information on a much larger sample of dogs, enabled them to associate specific behaviours with each lineage. For example, sheepdogs, historically bred for herding, tended to have a low prey drive and were highly trainable.
This would suggest that genetics can largely explain behavioural differences between dog breeds. But it is not, of course, the full story.
“When we look at behavioural traits across breeds, most of the variation we see can be accounted for by genetic factors,” says James Serpell. “But when we look at it within breeds, heritability is relatively low, suggesting that there is substantial individual variation due to non-genetic environmental factors.”
A 2022 study on dog genomics published in Science bears this out: it found that breed membership explained just 9% of owner-reported behavioural variation. “Breed is not especially helpful in predicting the behaviour of an individual canine,” wrote the researchers.
Serpell puts it into context for me. “Your Jack Russell terrier seems to display behaviours consistent with those of the terrier breed,” he says. “He is independent, headstrong and has a high prey drive. But that doesn’t mean that every Jack Russell will necessarily display those same traits.” In other words, I can’t just blame Morris’s behaviour on him being a typical terrier.
“The genetic make-up of a breed is only part of the story when it comes to behaviour,” affirms Dr Ilska. “It is also determined significantly by environmental factors – that’s why it is so important that dogs have a suitable environment and are well trained and socialised.”
Zazie Todd agrees. “Aspects other than genetics play a role, including epigenetics (which concerns the influence of environment and behaviour on gene expression without changing the DNA sequence), maternal care, early puppyhood experiences, learning history and events.”
Does a dog's early years impact its behaviour?
We got Morris as a rescue dog. He was a year old. We know little of his origin or puppyhood, though we were told that his knack for escaping and getting into mischief (there were rumours of an unfortunate guinea pig’s demise) had sent the previous owners over the edge. When Sue, the woman from the rescue centre, brought him round to meet us, she took one look at our garden and said “You’ll need to fence this properly”. We dealt with the fence. We installed a higher gate.
And we bought a Canicross harness and lead so that we could expend some of that surplus energy with running. But we also believed that with the right training, we’d soon have Morris walking to heel and coming back when he was called.
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We enlisted the help of a dog trainer and made great strides. So much so that we gained the confidence to work towards recall, first in the garden, then using a long line and eventually, letting him off the lead.
“You need to be the most interesting thing about the walk,” the trainer told us, advising us to carry squeaky toys and tasty treats, and to regularly change direction, run off, or even hide. It worked! At first.
But over the next few months, while he continued to be a model student in the home, he stopped responding to recall commands. We simply couldn’t compete on the ‘interesting’ front, when there were rabbits and squirrels to chase, badger setts to sniff around. It was as if once he’d picked up a scent or a movement, he became deaf and blind to us. He’d come back ‘in a minute’, then in five minutes… half an hour… at sunset.
We had to revert to keeping him on a lead, not just for our own peace of mind but for his safety. He could be shot for chasing livestock, hit by a car, stolen, trapped or attacked by another dog. Ten years on, he hasn’t grown out of it. And as vigilant as we try to be about the front door, the back gate, the garden boundary, he’ll still spot the tiniest opportunity to slip through, dig under or leap over… and he’ll be off. We’ve always wondered if there’s something we could have done – or could still do – to give Morris back his freedom. Or is his roaming behaviour too firmly entrenched?
Can you teach an old dog new tricks?
Todd believes it’s “never too late” to teach an old dog new tricks. “However, if a dog has a history of enjoying roaming, that behaviour becomes reinforcing for them, and they will look for more opportunities to do it.” This, says Todd, is where management comes in – leads, pet gates and fences, secure dog parks – and ensuring the dog is wearing ID in case it does get lost. “It also means giving dogs opportunities to engage in the behaviours they were bred for, though again, it’s not just about breed – individual dogs will have preferences for certain activities.”
We like to think Morris has a pretty good life, with plenty of walks and runs, as well as indoor and outdoor games with balls, treats, furry and squeaky toys. He has come far, in many ways. When we first had him, he would sit on a chair opposite us, eyeing us warily, not cuddle up next to us on the sofa; he wasn’t interested in toys and he snarled at other dogs. Okay, so his idea of the perfect day might involve sniffing out, chasing and killing small animals, but he’s also happy tearing along on his harness, shaking his furry monkey to death and curling up on our laps.
While the science may tell us that Morris is a terrier, a domestic dog and even an ex-wolf – it also tells us that he is an individual. Now, where’s he gone?
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Main image: a Czechoslovakian Wolfdog. Credit: Getty
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