Why do we ask our dogs to
heel on our left side?
The reason behind this could be as simple as 'it's a right handed world', that is the basic answer.
However humans are a very clever species and I think that if there was a good enough reason to
train your dog to the right, it would have been done in antiquity by our ancestors regardless of how
difficult it was; simply because if your dogs performed better than another man's dogs your chances
of eating and your family surviving greatly improved.
Back before any of the fun types of events in the modern 'doggy' world there were only 2 reasons
for owning a dog:
1. Hunting
2. Protection / Military Purposes
I suspect that the hunting duties slightly pre-date any protection duties, with the guarding instinct
noticed and perhaps harnessed after tribes clashed with each other, now let's look at each of these a
little more closely.
Hunting
The hunters of history used many weapons to take down their pray. Regardless of the weapon type
they all have the same thing in common - they require the hunter’s strongest, steadiest and most
accurate arm to control the weapons aim, power and delivery in order for the weapon to be
effective. Could you make a shot with a bow and arrow if you had a dog tethered to the arm aiming
the bow? One slight knock from the dog and you all go hungry.
It's not just dogs that this would affect, once man became mounted the rule of left transferred
across to the horse world too. In antiquity, when men wore swords, it was necessary to mount their
horses from the left side purely for safety purposes. Right handed warriors sheath their swords on
the left side, thus it is easier and safer to mount your horse from the left. It is because of this that all
of the tack for horses has always been made to be buckled and put on and taken off from the left
too.
When handling anything, we as humans lead with our strongest assets first. If we are right sided
then it will be our right eye we aim with, our right arm will be the strongest and you would test
suspicious ground with your right foot. It's your right foot that does all of the fine control work when
you're driving a car, you use your right foot to accelerate and break, if you have ever tried left footed
breaking you will quickly discover that you have a lot less control than you do with your right foot.
So it seems that 'because it's a right handed world' answers the question but there are other reasons
too.
Protection & Military Purposes
I dare say that dogs have been protecting man for almost as long as they have been hunting with
them, however it was the Romans who were the first to claim their use for military purposes. It is
said that the Romans started using dogs after a hard fought battle at Versella. The Battle of Versella
was fought in 101 BC, Roman forces clashed with the tribal warriors of the Teutons (not to be
confused with the Teutonic Order of Knights), a brave warrior society in which men and women
fought alongside each other.
The Romans’ claim this historical first because they wrote about it, and how they used dogs after this
battle to great success. However the Romans wrote about the tribal war lords of Western Europe in
early times and revered their war dogs even then. They also documented just how much effort was
taken to protect the massive beasts, each having its own personal armour and would often be better
protected than a lot of the warriors. This stands to reason as a lot of time and effort would have
been put into training these animals.
Protection
Let's concentrate on protection as the military aspect is very much
the same only in greater numbers and as a unit rather than just 1
man.
Opposite is a drawing of perhaps what a Roman soldier and his war
dog would look like, I did not draw this. This drawing is not very
accurate but it will serve us well in this demonstration.
Roman shields have always been rectangle in shape and when held
correctly protect a warrior from shoulder to thigh, very much like the
modern day police riot shield, in fact the police use them in the same
way as the Romans did all those years ago. If you replace the small
round shield with a correct shield for the time you will quickly see
how the shield not only protect the warrior from arrows and javelins
but also the dog.
As a shield is worn on the left are by a right handed warrior it quickly
became very important to have the dog on the left to; after all you
wouldn't want to spend all that time training only to have your dog killed in the first volley of missile
fire.
Protection does not just cover the War Dog, we must also include Guard Dogs too after the success
with dogs and hunting I think this would be the next logical step in the career path of dogs.
Dogs have a brain one-tenth the size of a human brain however all of the important sense receptors
required to make the perfect alarm system are much bigger.
If we break each of them down and we can quickly see the massive difference.
The Nose & Sense of Smell
This is perhaps a dog’s most important sense as it primarily interprets the world by smell.






As puppies dog’s noses include temporary heat sensors.
The part of the brain in dogs that controls smell is 40 times larger than in humans.
A dog’s sense of smell is about 1,000 to 10,000,000 times more sensitive than a human’s
(depending on the breed).
A human has about 5 million scent glands, compared to a dog, who has anywhere from 125
million to 300 million (depending on the breed).
Mucus covering on the dog’s nose captures scent particles.
A dog is capable of moving their nostrils independently which helps them locate which
direction the scent is coming from, or which way it went.
Ears and Hearing
Perhaps a dog’s second most useful guarding sense.




Dogs hear sound about 4 times the distance of a human with normal hearing.
Dogs can hear higher pitched sounds that humans cannot hear.
Dogs detect sounds in the frequency range of approximately 67 - 45,000 Hz (varies with
different breeds) compared to humans with the approximate range of 64 - 23,000 Hz.
Dogs have 18 or more muscles in their ears allowing them to be mobile, whereas a human
has only 6 and can only move their ears slightly, if at all.
The Eyes and Sight
Other than taste this is perhaps the weakest of all the dog’s senses.



Dogs see in colour but differently to humans, they primarily see black and white and shades
of blue and yellow.
Dogs can see best at dusk and dawn and low-light vision is much better than a human’s.
Dogs can recognize objects better when they are moving.
I have tried to list the dogs valuable guarding senses in order of efficiency, however there is one or
more other senses that dogs have that we don't.
E.S.P. Extra Sensory Perception & Masters of Body Language
Dog have the ability to sense things that we cannot or require a massive amount of training to grasp
thusly they fall into this ESP classification. Whether or not they are telepaths or just expert readers
of body language it is still a valuable guarding sense and is worthy of including.
Dogs can sense emotions, energy, chi, call it what you will. Dogs interpret human emotions such as
worry, anxiety, fear, anger, pity and nervousness, and weaknesses. All of the signs are likely to be
demonstrated by a would-be baddy.
It is possible that dogs require this skill in the wild to find a stable energy to follow as the leader of
their pack. The being with the strongest and most stable energy is the one they should look to, be it
themselves or another being around them, this is why dogs respond well to cool, calm, firm and
clear commands.
As you can see there is no wonder that the dog was and still is used to perform this job even today.
There is another theory of 'dogs on the left' comes solely from the modern military (World War II
onwards) and the men that left the forces and started teaching in the civilian world. I think this more
of a convenience rather than anything else however I have included the theory below.
Military tradition is based the warrior who was strongest (and mostly "highest ranking") in
unimpeded control of their right flank.
In military formations the highest ranking person is positioned to the right. If an officer, a sergeant
and a private are in uniform walking together the officer would be to the right with the sergeant in
the middle and the private on the left, because you as the owner/handler outrank your dog you
need to be on the right. However this custom comes from much earlier in time when shield walls
would clash.
When men ranked up into units they would present a wall of shields to the front and left hand side
and a wall of sharp things on the right like swords and spears.
Shields
As the enemy charged they would clash shields and funnelled around the sides of each unit, the
units to either side would either kill them or be protected from them by their shield.
Enemy
War dogs seem to be very much a western thing, predominantly seated in the Celtic tribes of Gaul
and the rest of North Western Europe.
The U.K. has a massive history of dog worship and canine fellowship this is perhaps why the British
are as mad about dogs as they are. Although the use of dogs are not exclusive to these lands as the
Japanese Shogunate had the Akita Inu at their side when they went to war, however they were more
regarded as a status symbol or a banner carrier rather than a true war dog, but even so they still
stood on the left so as to not hinder the drawing of the Katana.
It is common in today's dog training to train a dog to heel both left and right however it is easy to
see how tradition, safety, practicality and antiquity have shaped and continue to shape dog training
as we know it.
I hope this was as interesting a read for you as it was a research project for me, and I also hope it
help you answer the question as to "why on the left?"
© Gareth Johnston – October 2012
References
Dyce, K., Sack, W., Wensing, C. (2010) Textbook of Veterinary Anatomy 4th Edition Philadelphia:
Saunders (Elsevier)
Drake, R., Mitchell, W., Vogl, W. (2010) Gray’s Anatomy for Students 2nd Edition Philadelphia:
Saunders (Elsevier)