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Study Reveals Plane Travel Stressful for Dogs

March 14, 2025May 13, 2016 by Adrienne Farricelli CPDT-KA

With spring in full swing and summer around the corner, more and more people will be planning on going on a trip and perhaps this involves taking Fido along for a plane ride. If plane travel can be scary to humans, it should not be hard to imagine how it must feel to dogs. While dogs cannot talk about their fears or join a fear of flying chat room for support, there are several ways to assess how they react emotionally and physiologically to plane travel. A study conducted back in 2002, evaluated how dogs reacted during air transportation and their findings confirm that yes, air travel can be quite stressful to dogs. Knowledge is however power, so if you are planning to travel with your dog, there are many things you can do prior to departure day to make the trip less stressful for both you are your four-legged travel companion.

What The Study Found

In the study, physiological and behavioral reactions to air transport were studied by observing several beagles. Some beagles were sedated prior to travel and some were not. It was found that the cortisol concentration levels of these dogs were high after ground and air transportation. During their whole trip, the highest increase in heart rate was registered during the loading and unloading procedure. During the trip, dogs were found to spend 50 percent of their time lying down and they were found to be inactive 75 percent of time, except during take-off. Since these findings were similar even in the sedated dogs, this seemed to suggest that the sedative used (acepromazine) didn’t seem to affect the dog’s physiological and behavioral stress responses. This though could have been likely because it was administered 5 hours prior to take off when pharmacokinetic studies had shown that its sedative effect tend to last about 4 hours when given at a dose of 1.3 to 1.5 mg/kg.

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So How Stressful is Air Travel?

Not surprisingly, the study revealed that air travel is indeed stressful for dogs. Despite the study showing that transportation by road or by air were both stressful for dogs, their levels of stress though were lower than the levels measured by Beerda et al in a study where dogs where exposed to a loud noise, a falling bag or electric shock. However, there are chances that the discrepancies are due to the fact that, by the time the samples were collected, the dogs may already have habituated to the transport stressor.

dog crate — Keep the crate open the first few days.

What To Do

While the study revealed that both ground and air transportation can stress out dogs, there are many thing dog owners can do to reduce the stress. It’s quite normal for dogs to get stressed out by unconventional forms of travel due to the novelty of it and the fact that dogs are taken away from their comfort zones. Taking steps to get the dog more accustomed to travel can help make it less stressful and less scary, here are a few tips:

Purchase the crate your dog will be traveling in several weeks before the big travel date and get him accustomed to it from day one. Make the crate comfortable and cozy and make great things happen in it. Feed your dog his favorite treats in it and let him chew on his favorite bone in there. You can start off by keeping the door of the crate open at first.
As the study has shown, ground transportation can be as scary as air transportation. Get your dog used to traveling in his crate in the car weeks before travel date. Make fun trips to places your dog loves.
If you live near an airport, take your dog to the airport for brief “practice trips” and to get him gradually used to the noises. Make the trips there fun and don’t forget to bring high value treats to feed while there.
If the airport is far, you can play recordings of airport noises and planes taking off and landing while you play with your dog and feed him treats so he can form positive associations with the noises. Make sure you start paying these recordings at low volume first and then increase the volume gradually.
Since loading and unloading seems to be the most stressful part of the whole trip according to the study, it might not hurt to place your dog in the travel crate, place the crate on a cart, and stroll around as you talk to your dog in a happy, reassuring tone. Make it fun!
Do not sedate your dog! The International Air Transport Association’s Live Animal Regulations warns against tranquilizing pets for air travel. Sedatives may lower blood pressure and may interfere with an animal’s ability to regulate body temperature which can become problematic during airline travel. Also, sedatives may interfere with the dog’s ability to balance in the case there is turbulence during the flight.
Dr. Jeannine Berger, a board certified veterinary behaviorist suggests using Dog Appeasing Pheromone (DAP) spray in the kennel or the collar version which can be placed on the dog 24 hours prior to the trip. Anxitane (L- theanine), a natural anxiolytic can also be used help reduce your dog’s anxiety and fear.
According to a study by Wells DA, aromatherapy may also be helpful. A touch of lavender on a cloth in the car may help sooth mildly anxious dogs.
Walk your dog prior to having him board the plane and give him the opportunity to relieve himself.

” It is recommended that you DO NOT give tranquilizers to your pet when traveling by air because it can increase the risk of heart and respiratory problems. Short-nosed dogs and cats sometimes have even more difficulty with travel.”~American Veterinary Medical Association

References:

Renée Bergeron, Shannon L. Scott, Jean-Pierre Émond, Florent Mercier, Nigel J. Cook, Al L. Schaefer, Can J Vet Res. 2002 July; 66(3): 211–216.
Beerda B, Schilder MBH, van Hooff JARAM, de Vries HW, Mol JA. Behavioural, saliva cortisol and heart rate responses to different types of stimuli in dogs. Appl Anim Behav Sci 1998; 58:365–381.
Beerda B, Schilder MBH, van Hooff JARAM, de Vries HW. Manifestations of chronic and acute stress in dogs. Appl Anim Behav Sci 1997;52:307–319.
Wells DA. Aromatherapy for travel-induced excitement in dogs. J Am Vet Med Assoc 2006;229:964-967.

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Dog Nose Touching May Go Beyond Saying Hello

March 14, 2025May 8, 2016 by Adrienne Farricelli CPDT-KA

Many cat owners are familiar with cats touching noses when they meet and greet, but when dogs touch noses the behavior often leaves owners wondering why dogs engage in this type of meeting ritual. Perhaps it’s just because not all dogs meet this way and because we’re more used to seeing dogs greet by sniffing each others’ tails or groin areas rather than engaging in direct snout-to-snout contact. We thought that today it would be interesting discovering more about nose touching behaviors among dogs and their possible meaning.

Nose Touches in Cats

We know that cats are the nose-touching creatures par excellence (ever been woken up by the cold nose of cat greeting you and tickling your face with his whiskers?) but why has this greeting ritual become almost the norm? How did this behavior evolve?

It seems like this behavior starts early in the litter when kittens are small teeny-tiny fur bulls. At this stage, the kitten’s eyes haven’t opened as of yet, but their noses have fully functional touch receptors.

Nose touching is therefore the kittens’ way for making contact with their mom and “touching basis” with her. As the kittens grow, this behavior persists and cats use this friendly greeting ritual throughout their lives whether they’re meeting a new non-threatening cat for the very first time or they’re catching up with a buddy after their lengthy cat naps.

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Nose Touches in Dogs

As many of us have witnessed, dogs touch noses with other dogs too, only the behavior might not be as widespread as in cats.

While puppies are also born blind and their sense of touch is one of their earliest developed senses, the nose-touching behavior doesn’t seem to stick around much as in cats, why is that?

Yet, during their time in the litter, mother dogs and pups are often seen nose-touching. Stanley Coren, upon observing the interactions between a mother dog and her pups claims that “the opening contact was almost always a nose-to-nose touch.”

So why does nose-touching not stick around much in dogs, whereas, in cats it’s almost the norm?

Are we forcing dogs to meet in ways they're not comfortable with? — Are we forcing dogs to meet in ways they’re not comfortable with?

A Possible Explanation

Here’s just a thought we have. Perhaps it’s because dogs are often taken out on walks so they are more likely to encounter unfamiliar dogs, while cats are more likely to stick around nearby their colony and feeding areas and therefore are more likely to encounter cats they are more familiar with? Perhaps in dogs a butt sniff is preferred because a nose touch puts the dog in a too vulnerable position as it causes direct eye contact?

Something else worth pondering is whether dogs choose to nose touch on their own, or if they are forced to interact this way because that’s how dog owners often let dogs meet when on leash. We may never really know the right answers to these questions and they are certainly worthy of some research. However, the good news is that there is an actual study we can take a peak at that may reveal some interesting findings as to why dogs may engage in nose touching greetings.

puppy mother — Nose touches are reminiscent of early puppyhood.

What the Study Says

The study, published in the Journal of Animal Behavior, was conducted by Marianne Heberlein and Dennis Turner at the Institute of Zoology at the University of Zurich.

In the study, treats are hidden around a room. Afterward, special screens are placed in front of some areas where the treats are hidden. One dog is sent to search for treats, while another dog watches. The observing dog doesn’t know what happens exactly when the dog goes behind the screens.

To add a special twist to the study, sometimes the experimenters purposely removed the treats meaning that the dog got to eat the treats at some times but not in others.

Next, the dogs are allowed to interact with each other. Upon greeting each other, the dogs engage in some nose touches. This is where it gets interesting. If the dog had found some treats, when the observing dog was afterward sent to the room, he was likely to quickly go investigate the areas behind the screen. If the dog found no treats, when the observing dog was sent to the room he was less likely to investigate these areas.

What does this study suggest? It suggests that those nose touches aren’t just a mere way of saying hello, there’s more to it. Turns out those nose touches are an important communication tool for the purpose of exchanging information. Rather than a formal “hello,” in this case it’s as if the dog was saying something along the terms of ” Hey, have you encountered any goodies around here?” suggests Stanley Coren. Of course, with a dog’s stunning sense of smell, the answer relies within the breath.

Something similar may be going on when dogs are briefly separated for training sessions and then they are reunited. The separated dog may rush to nose touch the dog who underwent training to get any clues about treats being involved. Intrigued by this study, today we tried a brief experiment, we separated our Rottweilers and did a brief training session with our female Rottie using smelly treats (picture 1). Once done, our male Rottweiler was released and first thing first he quickly rushed to sniff our female near the face and then sniffed her anal area. Then off he went to look if there were any leftover crumbs on the floor! This is sure an interesting experiment dog owners with multiple dogs can give a try!

Food for thought? It has been speculated that dogs who roll in stinky dead things or poop do so to advertise their findings to their social group. It might be a way for dogs to brag about their findings along the terms of “Look what I found!” or perhaps just a way to share information about food sources with other dogs. If that’s the case, maybe that’s why familiar dogs don’t seem to mind having the other dog nose touch and investigate them?

More for Friendly Encounters?

At some point, we may wonder if nose touches are more likely to be geared towards friendly encounters, where there are reduced risks for conflicts. Stanley Coren in his book “Do Dogs Dream?: Nearly Everything Your Dog Wants You to Know” claims that cats nose touch with any cat they meet that appears nonthreatening.

So is nonthreatening the important keyword here, when it comes to nose touches among dogs?

Nose touching with an unfamiliar dog can after all be risky business as it’s preceded by walking up straightly to a dog and making direct eye contact. Turid Rugaas in her book “On Talking Terms With Dogs: Calming Signals” reminds us that dogs do not like to approach “head on” and would rather prefer to curving.

Stanley Coren further points out that dogs tend to use nose touches when greeting another nonthreatening species such as cats and kittens or when mother dog greets her puppies. He also mentions seeing it when adult dogs are greeting puppies or when meeting a “young human crawling across the floor.”

So are nose touches mostly reserved among dogs familiar with each other or animals that appear non- threatening? Do dogs take any precautionary steps to ensure that the nose touches are not perceived negatively by the receiver such as walking slowly or slightly squinting the eyes? These are sure some fascinating topics that hopefully will be further discovered one day!

References:

Do Dogs Dream?: Nearly Everything Your Dog Wants You to Know, By Stanley Coren, W. W. Norton & Company; Reprint edition (July 16, 2012)
Why Dogs Touch Noses: Communication and More, by Stanley Coren, retrieved from the web on May 8th, 2016.
Dogs, Canis familiaris, find hidden food by observing and interacting with a conspecific Marianne Heberlein*, Dennis C. Turner Animal Behavior, Institute of Zoology, University of Zurich.
Turid Rugaas, “On Talking Terms With Dogs: Calming Signals” Dogwise Publishing; 2nd edition (December 14, 2005)

Photo Credits:

Flickr Creative Commons, Bryan Alexander, Cats’ noses, Claw and Henra consider touching noses (CC BY 2.0)
Flickr Creative Commons, Thomas Edwards, The meeting, (CC BY 2.0)

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Surprise: Mother Dog Can Remember Her Pups!

March 14, 2025May 7, 2016 by Adrienne Farricelli CPDT-KA

The Disney cartoon The 101 Dalmatians and its subsequent movie seem to suggest that mother dogs remember their puppies and will do what it takes to be reunited with them, but is this only a Disneyland fantasy, or is there any truth to it? Can mother dogs recognize and remember their puppies even after they have been separated for some time? One may think they may not, as we are often reminded that dogs live in the moment, but fortunately, there are a few studies to give us an insight about long-term memory in dogs which takes us closer to the answer.

A Strong Bond

When puppies are born, mother and puppies strongly bond to each other courtesy of powerful hormones. Puppies, being born in a helpless state, totally depend on their mother during their first few weeks of life. Being separated at this time, causes great emotional distress in the young puppies causing sustained vocalizations and attempts to being reunited with the mother and siblings.

Most likely these responses are triggered by an evolutionary adaptation considering the many dangers associated with a vulnerable puppy being left alone, explains Steven Lindsay in the book “Handbook of Applied Dog Behavior and Training, Vol. 2: Etiology and Assessment of Behavior Problems.” The distress vocalizations emitted by the pups along with mother dog’s behavior in attempting to reunite with them therefore increases the chances for survival. It’s therefore expected that some level of lasting mutual attachment and attraction must develop between the vulnerable pups and their mothers, adds Lindsay.

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Proof of Remembering

After the their first weeks of life, pups start becoming gradually more and more independent. The puppies can soon eliminate on their own, start exploring their surroundings and start looking for alternate sources of food other than mother’s milk. Soon, the pups stay more and more away from their mothers and this is a good time for them to go to their new homes, but does this mean they will be completely forgotten? Peter G. Hepper may have the answer we are looking for. His study conducted back in 1994 revealed that at 4 to 5.5 weeks of age, puppies were able to recognize their mother and mothers could recognize their siblings and that olfactory cues were sufficient for this recognition to take place.

With this information in mind, the study went on to separate mom and pups and reunite them years later. Once the pups reached 2 years of age, (after being separated from their mother at 8 to 12 weeks) the pups and mom were therefore reunited and their behaviors were observed. Mother dogs showed signs of recognizing their now adult puppies and the adult puppies showed signs of recognizing mom. This shows that dogs are therefore capable of recognizing their kin even after 2 years of continuous separation!

Watch This Heartwarming Video of Mother Dog Being Reunited with Her Pups!

But Wait, There’s More!

While Hepper’s study was quite intriguing, William Carr and his colleagues at Beaver College decided to expand on Hepper’s study and this time they focused on seeing how siblings reacted after even longer separations from their mothers. In this study, mother dogs and their offspring were separated for several years and the puppies were observed to see how they reacted to their mother’s scent. The study revealed that the pups spent more time reacting to their mother’s scent than to the scent of another unfamiliar, like-breed dog, suggesting that dogs are capable of scent-mediated kin recognition even after many years of separation.

If you feel put aside as a human care giver (after all, aren’t we like our dog’s surrogate moms and dads? Research seems to suggest that) don’t feel bad: consider that the same study also found that the pups spent more time sniffing the scent of their initial caregiver than to that of a like-sex stranger after many months of separation. There is possibly even the chance that the dog could remember the caregiver’s scent even as long as 10 year after separation (Appel, 1999). These findings therefore seem to suggest that dogs seem capable of retaining olfactory memory and social recognition for their lifetimes. The familiar scent may perhaps not always be very missed, but for sure it’s not forgotten!
Soldier and Dog Reunion

Did you know? Charles Darwin owned a dog who was known for not being fond of strangers. After being away for 5 years, Darwin was impressed as to how upon being reunited he didn’t growl at him much when he called him. According to Darwin this was proof of a dog’s complex cognitive abilities.

References:

Long-term retention of kinship recognition established during infancy in the domestic dog, Peter G. Hepper Behavioural Processes, Volume 33, Issues 1–2, December 1994, Pages 3-14
Mekosh-Rosenbaum, V., Carr, W.J., Goodwin, J.L., Thomas, P.L., D’Ver, A., and Wysocki, C.J. (1994). Agedependent responses to chemosensory cues mediating kin recognition in dogs (Canis familiaris). Physiol. Behav. 55, 495–499
Appel J, Arms N, Horner R, and Carr WJ (1999). Long-term olfactory memory in companion dogs
Handbook of Applied Dog Behavior and Training, Vol. 2: Etiology and Assessment of Behavior Problems, by Steven Lindsay, Iowa State University Press; 1st edition (2001)
Darwin’s Dogs: How Darwin’s Pets Helped Form a World-Changing Theory of Evolution, by Emma Townshend, Frances Lincoln (October 27, 2009)
New Scientist, Fido stays faithful to the end, retrieved from the web on May 7th, 2016

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Five Fascinating Facts About Dog Hair Whorls

March 14, 2025May 6, 2016 by Adrienne Farricelli CPDT-KA

For those who do not know what in the world dog hair whorls are, here’s a brief explanation. Dog hair whorls are simply small patches of hair that grow in a spiral, circular manner. If you think your dog doesn’t have any hair whorls, think again. He likely has some somewhere on his body, but likely you just have never paid any attention to them.. at least until today. Also known as swirls, crowns or cowlicks, dog hair whorls are found in certain areas covered with hair on your dog’s body. Today, we will be discovering some fascinating facts about hair whorls in dogs, where you are likely to find them and what special meanings they may have according to some interesting studies.

1) Dog Hair Whorls Can Grow in Two Directions

What makes hair whorls stick out? Hair whorls are easily seen and felt because the hair is growing in the opposite direction compared to the rest of the hair. The direction of the hair can be clockwise or counterclockwise. Interestingly, the whorls on the left side of the dog’s body are usually counterclockwise while those on the right side are clockwise.

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2) They Come in Two Types

There are hair whorls and hair whorls. According to a study conducted by L.M. Tomkins and P.D. Mcgreevy, dog hair whorls can be either simple or tufted. Simple hair whorls have hairs that stem from a central, focal point and diverge into a flat swirling patter. Tufted hair whorls, on the other hand, have hairs that are converging from various directions to a central point, and, as the name implies, these hair whorls form a tuft, a collection of hair growing together at the base. The study found that among dogs tufted whorls were less common than simple whorls. The whorls on the dog’s elbows are examples of tufted whorles.

3) They Tend to Grow in Certain Areas

So now that we know what dog hair whorls look like, let’s go on a treasure hunt and find where they are more likely to grow! According to the study, whorls were found in ten different places, but the majority of dogs were found to have hair whorls in the chest, front legs (brachial axillae), elbows, and rump area. So let’s go a bit more in detail where they may be exactly found.

Chest whorls are commonly found in the middle of the dog’s chest. Two brachial axillae (one one each leg) are found in the upper front legs. Two elbow whorls (one on each elbow) are found in the back of the dog’s front legs, just nearby the bony prominence of the elbow. Two ischiatic whorls are found in the rear area, nearby the rectum. Some dogs also have whorls on the lateral areas of their face, sides of the neck and the abdominal area but these are considered atypical.

4) The Rhodesian Ridgeback Has Special Ones

Rhodesian ridgebacks are known for having a ridge of hair growing in the opposite direction on their backs. Along with the ridge, this breed has two hair whorls. According to the American Kennel Club standard for this breed, the ridge should have two identical crowns (whorls) opposite of each other. The whorls must not extend further down the ridge than one third of the ridge. The presence of ridge and crowns is so important in this breed that a lack of ridge is means for disqualification in the show ring and having only one crown or having more than two is considered a serious fault!

5) They Might Tell Something About Your Dog’s Personality

Interestingly, the placement and directions of dog hair whorls can be linked to right paw or left paw preference and can give some insights on the dog’s personality. Some pioneering work done on cattle found that the placement and direction of the hair whorl had a great effect on how anxious or bold the cattle were. No-one knows why, but there’s belief that it must be somehow related to skin and brain development in the embryo. Back to dogs, research done by Tomkins et al., 2012 found that, statistically, right-pawed dogs that had a counterclockwise whorl on their chest had twice the chance of succeeding in guide dog school when compared to left pawed dogs equipped with a clockwise whorl on their chest. Now that you know what in the world dog hair whorls are, you can see that whorls can mean a whole lot!

References:

Tomkins, L.M. and Mcgreevy, P.D. (2010), Hair Whorls in the Dog (Canis familiaris). I. Distribution. Anat Rec, 293: 338–350. doi: 10.1002/ar.21055
Tomkins, L. M. and McGreevy, P. D. (2010), Hair Whorls in the Dog (Canis familiaris), Part II: Asymmetries. Anat Rec, 293: 513–518. doi: 10.1002/ar.21077
Grandin T., Deesing M. J., Struthers J. J., Swinker A. M.: 1995. Cattle with hair whorl patterns above the eyes are more behaviorally agitated during restraint. Applied Animal Behaviour Science 46, 117–123
Tomkins L. M., Thomson P. C., McGreevy P. D.: 2012. Associations between motor, sensory and structural lateralisation and guide dog success. The Veterinary Journal 192, 359–367.
ABC Catalyst, Left Paw, Right Paw, retrieved from the web on May 6th, 2016
Correlation Between Hair Whorls and Different Types of Behaviors in Dogs, Lillebo Sophie, retrieved from the web on May 6th, 2016

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Study Reveals Dogs May See in Ultraviolet

March 14, 2025March 20, 2016 by Adrienne Farricelli CPDT-KA

We always knew that some animals such as birds, reptiles and insects (think bees) were capable of seeing ultraviolet, but a new study has revealed that dogs may be capable of seeing some level of ultraviolet too. In a previous article on how dogs see colors, we saw how dogs see colors differently than we do. For sake of comparison, dogs see color as a person who is red-green color blind (a deuteranope). Most likely, the reason dogs see colors poorly is because color detection wasn’t very important for dogs as their ancestors must have relied more on movement rather than color to capture prey animals. Compared to humans though, dogs are able to see in the dark better than us, an evolutionary advantage that came handy when the dog’s ancestors were busy hunting down nocturnal critters. With all this in mind, it would be interesting knowing what advantage there may have been for dogs seeing ultraviolet light.

Understanding Ultraviolet Light

What exactly is ultraviolet light? The normal light we are used to seeing is known as visible light. Visible light, which is visible to the human eye, is known for having wavelengths in the range of 400 to 700 nanometres (see picture below). Ultraviolet light, on the other hand, has shorter wavelengths than visible light, in the range of 400 to 10 nanometres, and on the opposite side of the spectrum, infrared light has longer wavelengths ranging from 700 nanometers to 1 mm. Ultraviolet light is invisible to the human eye because our lens absorb this type of light so it never gets to reach the retina. The only way people may see ultraviolet is when their lens are removed and not replaced, as it may occur in some cases of cataract surgery.

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♣ Curious Tidbit: There is belief that the artist Monet was capable of seeing ultraviolet after undergoing cataract surgery and this influenced his paintings causing him to paint flowers with a blue tinge.

Ultraviolet Vision in Animals

Many animals have UV-transparent lens allowing UV vision which helps them in different scenarios. In birds, ultraviolet vision may be helpful in courtship. Some birds have reflective patches on their feathers that are invisible to the human eye, but that birds can easily distinguish. These reflective patches are often displayed during mating rituals. Among blackbirds, females seem to respond more to males boasting bills with good UV reflectiveness during the period of territory establishment. On top of that, the waxy surface of certain fruits and berries reflect UV light so that the birds have an easier time identifying them. Birds aside, among bees seeing ultraviolet aids them in finding nectar, among rodents, it aids them in detecting UV-reflecting urine trails and among reindeer it helps them spot polar bears whose coats tend to blend in with the snow.

“There are many examples of things that reflect UV, which UV sensitive animals could see that humans can’t. Examples are patterns on flowers that indicate where nectar is, urine trails that lead to prey, and reindeer could see polar bears as snow reflects UV, but white fur does not.”Ronald Douglas, Discovery News.

A Breakthrough Study

Scientists always knew that several insects, birds and reptiles were capable of seeing ultraviolet. Among mammals, this ability was always considered rare and restricted to only a few species. A study published in the Proceedings of the Royal Society B, revealed instead that things are different than thought. Researchers examined the eyes of dead animals donated from zoos, veterinarians and slaughter houses ranging from hedgehogs to dogs and cats. The researchers found that the lens of many mammals including hedgehogs, dogs, cats, ferrets and okapis, allowed some ultraviolet light through. It was also found that animals who had lens that blocked UV light had retinas with a high number of cones, suggesting that the trade off for not seeing UV light is increased visual acuity. Moral of the story? If we were to see UV light, life would look quite blurry!

“Nobody ever thought these animals could see in ultraviolet, but in fact, they do,” Ron Douglas, the study leader and a biologist at City University London, England, told LiveScience.

What Does it Mean for Dogs?

The study revealed that the lens of dogs were capable of transmitting significant amounts of UVA in the range of 315 to 400 nm, suggesting that they are UV-sensitive animals. It was also found that species who were partially nocturnal had lens capable of transmitting UV, while diurnal animals had lens that prevented such wavelengths from reaching the retina. This may suggest that dogs can see UV light because they used to hunt nocturnal critters, while us humans relied more on visual acuity so to effectively see during the day. Further studies are needed though to determine exactly pinpoint how dogs may have benefited from seeing UV lights. Perhaps in their evolutionary past, detecting urine trails so to find prey animals would have been helpful and likely so was discerning a white bunny from a backdrop of snow.

“Now, if there is one thing humans are good at, it’s seeing detail, perhaps that’s why they have a lens that removes the UV. If they didn’t, the world would appear more blurred.” Ron Douglas

Fun fact: Your dog’s urine will glow if you point a black light, a special flashlight that produces ultraviolet light, over it. Indeed, black lights are often sold for urine-detecting purposes so puppy owners can spot soiled areas on the carpet and may effectively clean them up.

References:

Bright, Ashleigh.; Waas, Joseph R. (August 2002).”Effects of bill pigmentation and UV reflectance during territory establishment in blackbirds” (PDF).Animal Behaviour 64 (2): 207–213.doi:10.1006/anbe.2002.3042
Proceedings of the Royal Society B, R. H. Douglas, G. Jeffery, April 2014 Volume: 281 Issue: 1780
Live Science, Cats and Dogs May See in Ultraviolet, retrieved from the web on March 20th, 2016
Discovery News, Cats Have Super, Psychedelic Vision, retrieved from the web on March 20th, 2016

Photo credits:

Electromagnetic spectrum illustration showing visible spectrum location, by Spectre.svg: Tatoute, Creative Commons Attribution-Share Alike 3.0 Unported license (changes were made).

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Can Dogs Get Jealous of Other Dogs?

March 14, 2025March 6, 2016 by Adrienne Farricelli CPDT-KA

Dog owners who own more than one dog may at one time or another have to deal with dogs who are jealous of the other dogs coming close to the owner for attention. Many dog owners have been saying it for years, “my dog is jealous of other dogs coming near me,” but back in time, jealousy was thought of exclusively being a human trait. Yet, recent studies have found that what the dog owners were thinking was right, dogs do seem to feel jealousy, and if it’s not exactly jealousy, it’s something pretty close to it. Today we’ll discover more about the study and take a closer look into the dynamics behind dogs who are jealous.

Primordial Form of Jealousy

In the past, dogs weren’t believed to be capable of feeling jealousy because jealousy was always thought as being a feeling that required “complex cognitive abilities.” “Scientists tend to separate emotions into two categories: primary and secondary. Primary emotions, such as fear, anger, disgust, joy, and surprise, are considered to be universal. Secondary emotions such as guilt, shame, jealousy, and envy, are thought to require more complex cognitive processes.” explains Stanley Coren.

A dog has always been thought of not being capable of thinking in complex terms such as the anticipated loss of something of great personal value that’s associated with feeling jealousy. In order to feel jealousy the dog must think something in terms of: ” I better be careful, by looking at some past events, there’s a risk that my owner will start thinking that Scruffy is much better than me. I must take action to prevent this from happening.” However, dogs may be capable of feeling a more primordial form of jealousy, a more “in-the-moment” form versus the after-the-fact “mulling over” form, requiring more complex cognitive abilities. According to Clinician’s Brief this basic form of jealousy may have evolved from a need to “secure resources and as a survival mechanism for species with siblings.” In a recent past article we talked about sibling rivalry in dogs and the interesting revolutionary role it may have played.

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“Many people have assumed that jealousy is a social construction of human beings – or that it’s an emotion specifically tied to sexual and romantic relationships. Our results challenge these ideas, showing that animals besides ourselves display strong distress whenever a rival usurps a loved one’s affection.” ~Christine Harris

What the Study Says

The study, which was modeled from a study on human infants manifesting jealousy when their mothers interacted with a lifelike doll, was published in PLOS ONE and was conducted by University of California San Diego psychology professor Christine Harris and student Caroline Prouvost. The results of the study suggested that there might be a more basic form of jealousy affecting dogs. The dogs were found to exhibit behaviors suggestive of jealousy such as getting in between, pushing or snapping when the owner manifested affection towards an animated stuffed dog that barked, whined and wagged its tail. These manifestations were less likely to occur when the owner manifested interest in an object such as a carved pumpkin or a book.

“Our study suggests not only that dogs do engage in what appear to be jealous behaviors but also that they were seeking to break up the connection between the owner and a seeming rival.” ~ Christine Harris

Signs of “Jealousy” in Dogs

While more research may be needed before determining with certainty that dogs act out of jealousy, one things is for sure, when dogs feel that their owners are giving too much attention to another dog they give signs of not “liking” the interaction. The signs may be pretty obvious while some others may be more on the covert side.

Some dogs will approach as soon as they see another dog receiving attention and they’ll wriggle their way in between. Others may try to do things to revert the attention from the other dog to them such as pawing, rolling over or grabbing a ball and running over to the owner with it. Some other dogs may sit with their back facing their owner, perhaps even leaning against him, telling other dogs in doggy language “this person is mine, stay away!” just as they may do when resource guarding a bag of dog food. Should another dog approach, the dog may growl, lunge forward barking or even bite. Whether we call it jealousy or a form of resource guarding, one thing is for sure, it’s something that should be tackled as in some cases it may get out of hand.

Tackling Jealousy of Other Dogs

There are several ways jealousy of other dogs can be tackled, but one thing is for sure: using physical punishment and harsh techniques can make the issues much worse. Physically correcting the jealous dog may lead to defensive behavior or even a re-directed bite. On top of that, the jealous dog learns that when the other dog comes close he’s punished so he comes to dread the other dog’s presence even more. So what’s a good protocol? A good starting place is teaching both dogs to promptly respond to a verbal cue such as “lie down” or ” go to your mats!” at the very first signs of trouble so to diffuse any tension before things start building up. This is a good management practice to prevent squabbles in multi-dog households, but it’s also important to go to the root of the problem.

One way to approach this issue is removing the very thing the jealous dog wants the most: the owner’s attention. As soon as the jealous dog gives the most subtle sign of problems, the owner gets up and leaves. With no owner’s attention to stir things up, the dogs are left with nothing to fight over. If done with perfect timing, the jealous dog may eventually learn that his behavior leads to the owner leaving so he’ll reduce the jealousy episodes. Another method involves teaching the jealous dog that good things happen every time the other dog approaches. The jealous dog is therefore fed treats and given attention exclusively when the other dog comes near. When the other dog is away, the dog is ignored.

Obviously dogs with a history of serious fights, should be kept separated and owners should consult with a professional; however, for the correct implementation of behavior modification and for safety purposes, consulting with a qualified dog behavior professional specializing in force-free techniques is recommended for mild cases too. The sooner the jealous dog behavior is tackled, the better.

The Bottom Line

As seen, studies seem to suggest that dogs may show signs of a basic, primordial form of jealousy, but these studies aren’t conclusive. What may seem to us jealousy may sometimes be something else. For many years, we assumed that dogs were acting guilty and many dog owners had their own stories of dogs acting ashamed or guilty for doing something they weren’t supposed to, but recent studies found that dogs aren’t acting guilty but just responding to our behavior.

There are many interesting reads about animals manifesting “jealousy.” Below is an interesting video of wolves greeting a human. What do you see here? Do you think it’s jealousy, pure and simple resource-guarding, a matter of who gets to greet first or perhaps re-directed aggression due to high arousal levels? We would love to hear your thoughts in the comments section below!

References:

University of California – San Diego. “Dog jealousy: Study suggests primordial origins for the ‘green-eyed monster’.” ScienceDaily. ScienceDaily, 23 July 2014.
Clinician’s Brief, Jealous as a Dog, retrieved from the Web on March 6th, 2016
Elsevier. “What Really Prompts The Dog’s ‘Guilty Look’.” ScienceDaily. ScienceDaily, 14 June 2009.

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The Social Function of Dog Facial Markings

March 14, 2025March 5, 2016 by Adrienne Farricelli CPDT-KA

Let’s face it, as humans our faces offer a wide range of options when it comes to expressing our feelings. We can smile, frown, raise an eyebrow, wink and roll or widen our eyes. We can even wrinkle our nose, drop our jaw, purse our lips, blush or become pale. All of this happens courtesy of several facial muscles that allow us to create lines and folds in our faces and several movements so we can effectively convey our emotional states. When it comes to canines, things can be a tad bit more complicated as their facial muscles aren’t as developed as ours; however, Mother Nature has likely figured out a way to compensate for the deficit.

Facial Expressions in Dogs

Dogs may not have facial muscles that are as developed as humans, but they rely on several features of their faces to convey their emotions. A dog’s eyes may squint, blink, show whale eyes, or stare intently. The pupils may be dilated and the area above the dog’s eyes may appear tense (furrowed brow). A dog’s mouth may be closed tightly shut with tense muscles or opened in a relaxed manner. Yawning can take place. The corners of the dog’s lips (commissures) may be pulled back or the lips may be puckered forward or lifted in a snarl. The tongue may be hanging out relaxed or the edges may be curled (spatulate tongue). The tongue may also be flicking in and out or quickly licking the lips and nose. These are just a few of many facial expressions in dogs.

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Facial Markings in Dogs

Head markings seem to emphasize facial expressions, and well- delineated markings are often found in social animals with developed communicative systems, explains biologist and author Roger Abrantes in the book “Dog Language, An Encyclopedia of Canine Behavior.” There are therefore chances that facial markings in dogs are meant to enhance elements on the dog’s face which play a role in communication.

There is not much research conducted on this yet, but there may be chances that dogs with distinct facial markings may have a better time communicating than dogs who have fewer markings or lack facial markings altogether. However, just because some dogs don’t have distinct facial markings (think Labs and goldens), doesn’t necessarily mean they will struggle to communicate with other dogs. Dogs have many ways to communicate!

Dog Breeds with Facial Markings

Many dogs have distinct facial markings that may play a role in helping them communicate. Ever wondered why Doberman, Rottweilers and Bernese mountain dogs have copper or brown markings on their faces? In these dog breeds, the markings on their cheeks may help emphasize when they snarl, while the markings above their eyes may help emphasize their eye movements, suggests dog trainer and behavior consultant Liz Palika, in her book “The New Age Dog.”

And what about dogs with very dark muzzles such as German Shepherds, mastiffs, boxers and great danes? In this case, their dark muzzles may allow a dog’s pearly white teeth to stand out. Even some dogs who are entirely white may have some facial features that point out to the eyes and mouth. For instance, in the Samoyed or great Pyrenneese those dark-rimmed eyes, black noses and black lips may help emphasize these important areas of expression.

What Studies Have to Say

As mentioned, not much research has been conducted on dog facial markings, but there’s an interesting study conducted in Japan by Sayoko Ueda of the Tokyo Institute of Technology and Kyoto University. In the study, several species of the canidae family were divided in 3 groups. In group A were gathered specimens with irises that were lighter than their facial pupils and with other facial markings that made the eyes easy to locate. The animals in this group included the grey wolf, coyote and the golden jackal. In group B were specimens with only facial markings in the eye area and no visible pupils. The animals in this group included the maned wolf, the dingo and the kit fox. Finally, in group C were specimens that had no facial markings. The animals in this group included bush dogs, tanukis and African wild dogs.

The study concluded that animals equipped with eyes that were easier to locate belonged to species who lived and hunted in groups where eye communication was useful to bring down large prey. Whereas, animals with eyes that were more difficult to spot, were more likely to lead solitary lives. This seems to suggest that “eye-based conversations” must have played a crucial role in allowing animals to adhere to social functions such as living and hunting together.

“Various predators camouflage their eyes to increase their hunting success.” ~Cott HB (1940)

Types of Facial Markings in Dogs

As seen, the facial markings in different members of the canidae family may have served various adaptive functions, but what about dogs? Domestic dogs surely share a genetic basis for the conspecific gaze-communication observed in wolves. While dogs no longer hunt, they seem to understand the gaze signal of other dogs and humans. When it comes to gazing behavior directed towards humans, it was found that it was much longer in domestic dogs compared to gray wolves.

This seems to suggest that longer gazing behaviors directed towards humans may be a trait that has been selected artificially. In dogs though, their facial color patterns have quite varied during the selective breeding process by humans. Dogs today have different types of facial markings and some markings are distinctive of certain breeds, so much that they’re in some breed standards. Here’s a quick rundown on some of the most common facial markings in dogs:

Haggerty dot: a little circle of dark hair found on top of the head in the middle of a white blaze. Often seen in Boston terriers.
Blenheim spot: also known as the mark of “Duchess Thumb Print” is a chestnut spot in the middle of the forehead seen in Cavalier King Charles spaniels.
Blaze: a white strip in the center of the dog’s face usually between the dog’s eyes.
Kiss Marks: tan spots found on a dog’s cheeks and over the eyes.
Mask: a dark shading on the dog’s front portion of the skull.
Spectacles: markings over or around the eyes or from eyes to ears.
Muzzle bands: a white marking around the muzzle.

References:

The New Age Dog Kindle Edition by Liz Palika Renaissance Books (July 8, 2014)
Dog Language – An Encyclopedia of Canine Behavior Kindle Edition
by Roger Abrantes, Amazon Digital Services LLC, November 27, 1997
Ueda S, Kumagai G, Otaki Y, Yamaguchi S, Kohshima S (2014) A Comparison of Facial Color Pattern and Gazing Behavior in Canid Species Suggests Gaze Communication in Gray Wolves (Canis lupus). PLoS ONE 9(6): e98217. doi:10.1371/journal.pone.0098217
Cott HB (1940) Adaptive coloration in animals. London: Methuen. ix+508+plate48 p.
American Kennel Club, Glossary, retrieved from the web on March 5th, 2016.

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Five Ways Dogs May Say I Love You

March 14, 2025February 12, 2016 by Adrienne Farricelli CPDT-KA

Until the day your dog can talk, you’ll never likely hear him pronounce “I love you,” and in the meanwhile, don’t expect him to purchase you a Hallmark card or some balloons with those famous words printed on top. And forget about receiving a box of chocolates or a flower bouquet from your dog when Valentine’s Day is around the corner; dogs know better ways of demonstrating the affection they feel towards their favorite people. The best part is that dogs say the canine equivalent of “I love you” in dog speak on a daily basis, too bad that we’re often too busy to take notice and their message is often missed! And for those skeptics frowning upon a dog’s ability to demonstrate primary emotions such as love, sadness and fear, they should consider that whether dogs are capable of feeling emotions is no longer a subject of debate. It has been scientifically proven that dogs share the same brain structures that produce emotions in humans.

The fact that animals have primary emotions—and intelligence—is no longer the subject of debate. Primary emotions like anger, sadness, fear, and love are not in contention. ~Nicholas Dodman

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1) Gazing into Your Eyes

When your dog adoringly gazes into your eyes with his soft brown eyes, you’re not imagining things if you get a warm fuzzy feeling of being loved. A study conducted by Miho Nagasawa of Azabu University in Japan and his colleagues found that when owners and dogs shared a long mutual gaze, both species had higher levels of oxytocin in their urine compared to those of owners of dogs sharing a shorter gaze. Oxytocin, also known as the “cuddle hormone,” has been associated with nurturing and social bonding and Nagasawa and her colleagues concluded that their research provided “a manifestation of attachment behavior.”

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“When owners interact with their dogs, both sides have surges in oxytocin. That puts a check in the ‘dogs can love’ box.”~ Karen L. Bales

2) Greeting You at the Door

Does your dog get all happy and excited the moment he hears you opening the door? Neuroscientist and author of the book: “How Dogs Love Us,“Gregory Berns may have an explanation.

Based on his brain imaging research, Berns found that dogs could clearly discern the scent of familiar humans and their smell sparked activation of their reward response center in the brain, an area called the caudate nucleus.

Berns claimed that the reward responses in dogs were analogous to the brain responses seen in humans, such as when “seeing a person that’s a friend or someone you like.”

Of course, there are likely other mechanisms at play when it comes to those greeting rituals such as relief from boredom and loneliness and even an element of curiosity, but these are in addition to being glad to see us.

“What we’re finding with the imaging work is that dogs love their humans—and not just for food. They love the company of humans simply for its own sake”~ Gregory Berns

3) Listening to Your Voice

Dogs aren’t just tuned into their sense of olfaction, does your dog wag his tail when you talk to him in a happy tone of voice? You may not imagining things when you assume Rover must “love” hearing your voice.

In Budapest, Attila Andics, a neuroscientist along with his team of researchers, used MRI technology but this time to study the brain activity of dogs upon hearing human voices.

In this study, it was found that dogs, just like humans, have dedicated voice areas in their brains and therefore happy human voices were capable of lightening up the dogs’ temporal pole, the part of the brain responsible for processing acoustic information.

This shows that dogs are physically wired to pick up on our subtle mood changes and they are very good at tuning into our feelings. It’s evidence explaining why the bond between humans and dogs is so close, suggests Andics.

“We know very well that dogs are very good at tuning into the feelings of their owners, and we know a good dog owner can detect emotional changes in his dog – but we now begin to understand why this can be.”~ Attila Andics

4) Seeking Comfort from You

Does your dog rush to you for comfort after being exposed to some frightening event or stimulus? Scientists at the University of Veterinary medicine in Vienna found striking similarities between the bond between dogs and their owners and the bond between between human parents and their children.

The study conducted by Lisa Horn from the Vetmeduni’s Messerli Research Institute, provided evidence for the similarity between the “secure base effect” found in dog and owner relationships and child and caregiver relationships.

The owner’s presence played an important role in enticing the dog to behave in a confident manner. Andics also confirms that dogs act similar to babies when they’re frightened and seek comfort from humans with whom they have formed a bond, a totally different reaction compared to cats and horses, animals who would rather flee than seek support!

“One of the things that really surprised us is, that adult dogs behave towards their caregivers like human children do. It will be really interesting to try to find out how this behavior evolved in the dogs with direct comparisons.” ~Lisa Horn

5) Showing Unconditional Love

There no scientific study or research to back this up, but it’s crystal clear, dogs love us for what we are. We can be rich or poor, happy or sad, young or old, no matter our income, social status or whatever life throws at us, we can always count on our dogs.

Dogs don’t hold any grudges toward us regardless of how many mistakes we may have done. It’s no wonder why dogs are considered man’s best friend, whenever it comes to love, dogs can always outperform us and they’re naturally equipped with an endless capacity for unconditional love that they’ll willingly dole out for a lifetime.

Regardless of what happens, dogs will always think we’re wonderful and they’ll love us with all their heart. And the best part of all is that they can say “I love you” without using any words at all!

“The world would be a nicer place if everyone had the ability to love as unconditionally as a dog.”―M.K. Clinton

References:

Oxytocin-gaze positive loop and the coevolution of human-dog bonds, by Miho Nagasawa et al. Science Vol 348, Issue 6232, 17 April 2015
Scientific American, “Is the Gaze from Those Big Puppy Eyes the Look of Your Doggie’s Love?, retrieved from the web on February 12th, 2016
Veterinary Practice News, “Animals Have Emotions, But What About ‘Theory Of Mind’?” by Nicholas Dodman, BVMS, DACVB, retrieved from the web on February 12th, 2016
The Why Files, The Science Behind the News, University of Wisconsin Board of Regents, retrieved from the web on February 12th, 2016
io9, We Come From the Future, Why Are Dogs So Insanely Happy to See Us When We Get Home? by George Dvorsky, retrieved from the web on February 12th, 2016
Scent of the familiar: An fMRI study of canine brain responses to familiar and unfamiliar human and dog odors, Gregory S. Berns, Behavioural Processes Volume 110, January 2015, Pages 37–46
BBC News, Dogs’ brain scans reveal vocal responses By Rebecca MorelleScience reporter, BBC World Service, retrieved from the web on February 12th, 2016
Horn L, Huber L, Range F (2013) The Importance of the Secure Base Effect for Domestic Dogs – Evidence from a Manipulative Problem-Solving Task. PLoS ONE 8(5): e65296. doi:10.1371/journal.pone.0065296

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Discovering How Dogs See Color

March 14, 2025January 30, 2016 by Adrienne Farricelli CPDT-KA

When we look at a rainbow, do our dogs see the same colors as we do? Understanding how dogs see colors can help us get a better grasp on how they perceive the world around them. Discovering how dogs perceive colors is not only a matter of satisfying our curiosity, but also a matter of becoming better informed owners. For instance, do dogs have a hard time finding toys of a certain color? Do colors affect a dog’s ability to fetch a toy or a dog’s performance in canine sports? By understanding better a dog’s color vision, we can gain a glimpse of what it must feel like to see the world through the eyes of a dog.

Dispelling the Myth

For many years, we thought that dogs could only see in black and white. The belief that dogs could only see in shades of grey, relying on different levels of brightness to identify the outlines of items, has been so widespread that still as of today we may stumble on people making remarks that it’s an unnecessary practice to pick a specific color of dog toy considering a dog’s monochromatic vision.

While there are several mammals that are monochromats (capable of seeing only one color) such as the seal, sea lion, walrus, dolphin and whale, turns out, dogs aren’t part of this classification. Research has found that, unlike what we have heard for many years, dogs can actually see colors, but quite differently than how we perceive them.

Dog Color-Vision Study

A study conducted by Jay Neitz et al. at the University of California, Santa Barbara, has revealed interesting findings on color perception in dogs. The dogs were basically exposed to the presentation of three light panels in a row–two of the panels were of the same color, while the third was different.

The goal for the dog was to discriminate the panel that was different. Every time the dog was successful, he was rewarded with a treat. The study found that dogs are capable of seeing colors, but they see fewer colors than we do.

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A Matter of Cones

Cones are the photoreceptors responsible for allowing us to perceive the details of colors. These photoreceptors send signals about color to the brain.

Humans have three kinds of cones that identify red, blue, green and yellow wavelengths. It is through the combined activity of these cones that humans have a full range of color vision, explains Stanley Coren.

Dogs instead, like most other mammals, have only two cones, one cone which is sensitive to blue, while the other is sensitive to yellow. This means that, unlike humans, who are trichromats, dogs are dichromats, meaning they can see two colors.

What does this mean to us? It means that we should start re-considering the way dogs see colors so we can make necessary adjustments.

Seeing Like a Dog

If we want to put ourselves in our dog’s shoes, we can say that our dog’s color vision is roughly similar to that of a person who is red-green color blind (a deuteranope).

As seen in the picture featuring the green and red apple, we can see how it is difficult for the dog to discriminate between these two colors.

They have a much better time though with detecting blue and yellow. So what does this mean for dog owners? Based on these findings, it means that we should choose toys that are blue or yellow, which is sort of not easy considering that many dog toys are orange and most Kongs are bright red.

This seems to prove us that the dog toy industry is more interested in selling toys that are more appealing to us rather than our dogs! So yes, whether you are choosing a Frisbee or a ball to play fetch, your choice of color is important if you want it to stick out. Choosing a red toy that is hard to distinguish from the green grass of the dog park can make life difficult for Rover.

“Overall, if we want dogs to distinguish between colors, the best colors to use are blue and yellow.” Dr. Sophia Yin, D.V.M, M.S

Colors and Dog Sports

And what about dog sports? In the obstacle jumping industry for horses, colors have been used wisely for quite some time, as horses, just like dogs, also have two-color, dichromatic vision. Therefore, to help horses judge the obstacles, jump rails are often painted a different color from the surrounding landscape.

Also, studies have found that there were less chances for horses to knock down a rail if it was painted in two or more contrasting colors. As dog agility shares many features with horse obstacle jumping, this explains why dog agility equipment colors are important. It’s therefore not a coincidence that those contact zones in dog agility are often painted yellow with contrasting shades of blue!

A Look Back

At this point, one may wonder, why do dogs see colors in less detail than humans? It likely must have something to do with our evolutionary past. There are various theories as to why we have full color vision, when many mammals do not.

One may assume that the dog’s ancestors must have relied more on movement than color to capture prey animals; whereas, primates relied more on color to attain food.

The Fruit Theory suggested that primates relied on the ability to see color for the detection of red and orange fruit against a mature leaf background, while the Young Leaf Theory suggested that it was a matter of seeing young leaves. This way primates would spend less time and energy picking unripe fruits.

Interestingly, neuroscientist Mark Changizi has a totally different theory.”Our vision was never well optimized for that. My hypothesis was that it was about sensing emotions or health on the skin of others.” Looks like more research is needed in this interesting field!

How Dogs See Rainbows

So how do dogs see rainbows? “Instead of seeing the rainbow as violet, blue, blue-green, green, yellow, orange and red, dogs would see it as dark blue, light blue, gray, light yellow, darker yellow (sort of brown), and very dark gray.

In other words, dogs see the colors of the world as basically yellow, blue and gray” further claims Stanley Coren.

References:

Color vision in the dog, Neitz J¹, Geist T, Jacobs GH, Vis Neurosci. 1989 Aug;3(2):119-25.
Dr Sophia Yin: Can Dogs See Color? And How Do We Know?,
Wikipedia: Evolution of Color Vision
Wikipedia: Evolution of color vision in primates
Wikipedia: Equine Vision
Psychology Today: Can Dogs See Colors? by Stanley Coren.

Photo credits:

Simulation of the normal (above) and dichromatic (below) perception of red and green apples, by Limbicsystem, Author: Alex Wade CC BY 2.5 (changes made to add details as to how pertains to dogs)

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Dogs Learn Words Courtesy of Fast Mapping

March 14, 2025January 7, 2016 by Adrienne Farricelli CPDT-KA

It’s Talent Thursday, and learning to associate words with certain items is certainly an impressive talent, especially when it comes to dogs! How many words can a dog learn? Rico, the border collie, has shown the ability to learn over 200. Juliane Kaminski from the Max Planck Institute for Evolutionary Anthropology along with colleagues, has studied this remarkable border collie. The results of the study clearly demonstrated that Rico was capable of getting 37 out of 40 items correctly! In order to properly study this dog, a scientific approach was needed to rule out other phenomena which could have explained this dog’s ability to discriminate words from one another.

Ruling Out the Clever Hans Effect

One phenomenon to rule out included the dog’s reliance on subtle cues sent from the owner. Dogs are very attentive to our body language, so it’s easy for them to select certain items simply because we are moving our heads in that direction or looking at the item. We may do this unintentionally, but dogs feed into these cues.

Many years ago, a horse going by the name of Clever Hans, was found to be capable of resolving arithmetic calculations. The horse was asked to solve a math problem and he would tap his hoof to give the answer. After an investigation conducted in 1907, psychologist Oskar Pfungst proved that the horse wasn’t actually counting, but was actually responding to involuntary, subtle cues sent out by his trainer! Turns out the horse was quite sensitive to the building tension of his trainer when he was asked to solve a math problem and the release of tension when he got to the correct number. This release of tension therefore informed the horse that it was time to stop tapping his hoof. Because of this phenomenon, now, people studying animal cognition refer to it as “The Clever Hans effect.”

Out of Sight

So in the study of Rico, the border collie who knew 200 words, it was important to rule out the Clever Hans effect. This was done by asking the dog to fetch the toy by its name with the owner in another room. This prevented the dog from reading the owner’s cues (such as looking at a particular item) and would have proven that this dog was actually capable of fetching the correct toy because he really associated the word with that particular toy. The results revealed that Rico was actually, capable of understanding words and his vocabulary proved to be quite broad when compared to the vocabulary of parrots, apes, sea lions and dolphins!

Proof of Fast Mapping

So if Rico wasn’t relying on any subtle cues sent by his owner, how was he capable of learning so many words? Turns out, he was utilizing the same mechanism humans use known as “fast mapping.” Fast mapping is a mental process where concepts are learned based on a single exposure. Children during the language acquisition phase, learn many words each day by relying on this mechanism.

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To prove that Rico was capable of learning based on a single exposure, a novel item was introduced among familiar ones in a single exposure. Rico was then asked to retrieve the new object by using the novel word. So Rico went off to select the toy, and possibly, through a process of elimination, determined that the novel word must have been used to refer to the novel toy.

Referent Selection and Retention

In order to learn through fast mapping, two conditions needs met: referent selection and referent retention. In referent selection, the dog must associate a word with a particular item; whereas, in referent retention, the dog must be able to store the word in his memory for later use. After learning a new word after only one exposure, Rico was tested a month later to see if he retained the understanding of that word. Surprisingly, Rico was able to correctly retrieve the item as much as 50 percent of the time, a success rate that matches that of a 3-year-old child!

Rico’s behavior was quite remarkable indeed. Further proof of understanding words was proved by other dogs with an even more vast knowledge of words. Betsy, another border collie, showed she was capable of understanding over 340 words, but as of 2010, Chaser, another border collie beats all with a vocabulary of an astounding 1022 words! Yes, you read right, that’s 1022 words!

This can make us wonder if border collies have superior cognitive abilities when it comes to understanding the meaning of words. If we think of it, this breed was selectively bred to herd and throughout the years has shown a remarkable ability to understand voice commands and whistles, so perhaps, there may be a genetic predisposition at play. Yet, with the right training, any dog regardless of breed can learn the meaning of words if you know how to teach them.

Words From Rover’s Perspective

As much as the behaviors of Rico, Betsy and Chaser are impressive, they are still a far cry from the way humans perceive words. Humans have the cognitive ability to perceive abstract concepts such as the words love, friendship and sincerity. Dogs on the other other hand, are more down to earth, and mainly learn words that are under the form of objects or actions.

Even though your dog may seem to understand a sentence such as ” do you want to go out?” and gets all excited when he hears that as it’s always followed by you walking by the door and opening it, he may not understand more complex concepts or phrases such “you can’t have the cookie now” as the word “now” or “can’t” isn’t understood, but since the word cookie may be, likely your dog may get all excited and then feel frustrated when he doesn’t get the cookie.

Your dog may not know an impressive number of words compared to Rico, Betsy or Chaser, yet consider that many dogs respond to cues present in their environment which often speak for themselves. For instance, the noise of the leash becomes synonymous with walk, the noise of the food bag becomes synonymous with dinner, when you wear your shoes, your dog knows that means you’re heading out, when you grab the car keys it likely (and hopefully!) means car ride and when your dog hears your keys making contact with the key hole it means you are returning home. So now that you know that dogs respond best to concrete concepts such as the names of objects or action words, it’s time to put your dog to test and enroll him in a program that extends his vocabulary!

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