Do dogs know other dogs are dogs?

It’s not the philosophical conundrum it appears. New research helps explain how Fido perceives his fellow pets

Do you see dogs everywhere?

 3415_1148228981856563_479399560376361517_nMy ears perk up to the jingle jangle of metal-on-metal, hopeful that it predicts a dog and his collar, disappointed when it turns out to be keys on a belt (boring).

A person walking down the street with their arm outstretched holds the promise of a leash with a dog on the other end (sometimes it’s a stroller holding a kid. Oh well).

From a distance, my eyes play a cruel trick on me, where shopping bags are dogs and dogs are shopping bags until I get close enough and one wins out (obviously I’m rooting for the dog).

But catch any part of a tail, and I know I’m in. You could say my motto is, “dog, until proven otherwise.”

How about dogs?

Does a dog know, merely by sight, that an approaching being is a fellow dog? Before you answer, remember this: Canis familiaris is the least uniform species on the planet. Members of this species come in a wide range of body shapes and sizes from itty bitty teeny weeny to absolutely ginormos. Adult members of this species appear as tight little packages, huge weightlifters, lean ballerinas, elongated hotdogs and everything in between.

Does a Pug look at an Afghan Hound and say to themselves, “Hello, dog!” or does a Pug look at an Afghan Hound and say, “WHAT IN THE WORLD ARE YOU?” and only after olfactory investigation (smelling) does the Pug realize, “Oh my goodness. How silly of me. You’re a dog. Sorry for the confusion my large, long-snouted compatriot.”

A number of researchers have essentially wondered what Pugs think of Afghan Hounds. Are dogs able to identify other dogs solely by appearance, they wondered? If olfactory cues are taken out of the equation, would a dog still know another dog when he sees one?

A team of researchers based in France took on this question, publishing their findings in Animal Cognition in 2013. Nine companion dogs joined as study subjects. They all had basic training and extensive experience with both dogs and people, and notably, the participants weren’t uniform in appearance — two were purebred (Border collie and Labrador), and the rest were mutts. Below are the study subjects in all their photographic glory (while they are all my favorites because they are dogs, I vote Cusco winner of Best Eyeliner and Best Ears, while Babel, Cyane and Sweet tie for Most Photogenic).


The experimental setup was simple enough: the nine subjects saw two screens, one on the right and one on the left with a divider between. In each trial, two images would appear simultaneously on both screens, and dogs were reinforced with a click and rewarded with a treat for approaching the “correct” screen — more on that in a moment. Here’s what the experimental layout looked like:


To find out if dogs could ID other dogs based on appearance alone, the researchers first had to create a common language with their dog subjects. They did this with the help of three training sessions where dogs received a treat only when they approached the screen that had a picture of a dog’s face. Importantly, the same dog picture was used throughout the training sessions. During the training phase, the other screen was either all black, all blue, or had a picture of a cow’s face. The dog subjects were not rewarded if they approached any of the other non-dog pictures. This created a common language: “You are rewarded for approaching this ‘dog’ image, nothing else.”

To proceed, the dogs had to approach the dog image 10 out of 12 times in two consecutive sessions, which is better than approaching ‘dog’ by chance. All nine dogs were able to do this. Common language secured!


Then came the test. Dogs were presented with a wide variety of never-before-seen dog faces paired against never-before-seen non-dog faces. As before, dogs had to approach the dog image and avoid the non-dog image to get a treat. This was no longer an easy feat as the dog images now captured dogs’ vast morphologic diversity in shape, color, size, head shape, ear position, you name it. On top of that, the dog images were now pared against a wide range of non-dog faces including human faces as well as domestic and wild mammals like cats, sheep, gerbils, cows, rabbits, reptiles, and birds, among others. Images were presented head-on (full face) or as a profile. Below are examples of faces dogs saw in the study:



The dogs prevailed! The nine subjects successfully identified “dog” from “non-dog” faces. Some dogs, like Babel, Bag, Cyane and Vodka, were able to do so quite quickly, taking few sessions to approach the required 10-out-of-12 dog images. Other dogs, like Bahia and Cusco, were slower on the pickup and took more sessions to identify “dog” from “non-dog” (dog subjects needed anywhere from 2 to 13 sessions to meet criteria). This is not to say, of course, that Bahia and Cusco don’t know a dog when they see one. The researchers highlight that a number of factors — like dog personality, learning styles and strategies, and motivation — can affect dog behavior and performance, particularly when it comes to this type of task.

Even so, the study suggests that despite their wackadoodle appearances, dogs can identify other dogs by sight alone. Dogs seem to have a sense of who (or at least which images) falls in the category of “dog” and who does not. Exactly which features dogs use when tuning into “dog,” though, the current study can’t say. They offer that as a natural next step in the research.

Autier-Dérian D, Deputte BL, Chalvet-Monfray K, Coulon M, Mounier L. 2013. Visual discrimination of species in dogs (Canis familiaris). Animal Cognition, 16, 637—651.

This article was originally published by Scientific American.

Science Post: Variety of Genetic Risk Behind Bone Cancer in Dogs

Dec. 12, 2013 — Osteosarcoma, a type of bone cancer, is a rare but very aggressive form of cancer that primarily affects teenagers. Among some large-sized dog breeds the disease is much more common, but otherwise osteosarcoma in humans and dogs is very similar. In the current study, the researchers compared the genome of sick and healthy dogs from three different breeds to find inherited risk factors for the disease.

“The key is that we find many different risk factors within each breed. We already knew that greyhounds, Rottweilers and Irish wolfhounds are at increased risk of developing bone cancer and our results explain much of the increased risk,” said Emma Ivansson, scientist at SciLifeLab and Uppsala University.

The study demonstrated that each breed has its own risk genes, but these genes converge in common disease mechanisms. Some genes are known cancer genes in humans, while others are completely new discoveries. The researchers also studied one of the risk factors in more detail and found a new regulatory signal that leads to increased gene expression in bone cancer cells from humans.

“Our results show that the pathways involved in bone formation and growth are important for the disease. Because of the great similarities between bone cancer in dogs and humans, we believe that our findings may contribute to an increased understanding of how bone cancer develops in humans,” said Kerstin Lindblad-Toh, professor at Uppsala University and Co-Director of the SciLifeLab and Director of Vertebrate Genome Biology at the Broad Institute.

The researchers are continuing to study the identified risk factors to understand more about how they affect tumor development and to see whether different risk factors respond to different types of treatment.

Story Source:

The above story is based on materials provided by Uppsala University. The original article was written by Anneli Waara.

The truth is, there is no evidence that supports the label “hypoallergenic” with respect to dogs

I hear this all the time, “Oh, I got this “….” (insert doodle, poodle, etc) because it’s hypoallergenic and doesn’t shed!
Well, They’re in for a shock. There’s actually no such thing as I hypoallergenic dog, and I would question the breeder who sold it to you, under the premise that it was.  This is one of those scenarios, I find myself struggling to smile and walk away, as I don’t want to be the one to burst this new puppy owners bubble!

A study from Detroit’s Henry Ford Hospital has found that poodles, Portuguese waters dogs (like the Obama’s pet, Bo), and other supposedly hypoallergenic dogs produce no fewer allergens than their shedding counterparts.

Researchers focused on 173 homes, each with one dog and a newborn baby. Sixty different breeds were represented in the sample, including 11 supposedly hypoallergenic ones. When scientists analyzed dust samples from the floors of the homes’ nurseries, they did not find any significant difference in the allergen levels in the homes with hypoallergenic dogs versus those with standard, shedding pups. “The idea that you can buy a certain breed of dog and think it will cause less allergy problems for a person already dog-allergic is not borne out by our study,” says Christine Cole Johnson, Ph.D., the study’s lead author.

An adorable little Havanese, a breed that is often marketed as ‘hypo-allergenic’.

The allergenicity of “hypoallergenic” dogs

It’s a primitive social urge in humans to interact with dogs. So much so that many people found to be clinically sensitive to dogs will own them anyway. In this context, it is not surprising that the search for dogs that elicit a minimal allergic response would claim so much energy, but are there such things as “hypoallergenic” dogs? Vredegoor et al. look at that question in this month’s issue (J Allergy Clin Immunol 2012;130:904-909.e7).
The authors examine levels of the primary dog allergen, Can f 1, in samples from dog fur and skin, and settled and airborne dust from “hypoallergenic” dogs (Labradoodles, Poodles, Spanish water dogs, and Airedale terriers), normal allergenic dogs (Labrador retrievers), and a variety of breeds and mixed breeds that made up the control group. Their results are paradoxical and even ironic.
Poodles and Labradoodles had the highest levels of Can f 1 in their coat and skin; Labrador retrievers had the lowest. Hair and dander shedding was highest from Airedale terriers. Vredegoor et al. report that environmental levels of Can f 1 were not significantly different between “hypoallergenic” dogs and their allergenic counterparts, though homes with covered floors had overall lower environmental levels than homes with exposed floors. The authors note that other identified canine allergens, such as Can f 2 and 3, were not screened due to lack of available methods for analyzing large sample sizes.
The authors also collected information from owners by administering questionnaires. Dog-allergic owners reported much fewer symptoms with the breeds thought to be hypoallergenic and did not report having different house-cleaning practices than non-allergic owners. It was noted that recent swimming by the dogs had an overall effect of lowering allergen levels and Vredegoor et al. speculated that this could contribute to the lower levels found in Labrador retrievers, which are frequent swimmers.
Vredegoor et al. conclude that there is no evidence that supports the label “hypoallergenic” with respect to dogs, so we asked the authors to comment on a possible explanation for the number of dog-allergic owners who reported experiencing fewer symptoms with certain dogs: Senior author Esmeralda J.M. Seegers-Krop replies, “We believe the health effects can be a kind of placebo effect in these people. It has been seen in cat allergic people as well (they report not to be allergic to their own cat but only to other cats).”

More reading on the topic:

NYTimes – The Myth of the Allergy-Free Dog

Time Magazine – Poodles, Labradoodles and Portguese Water Dogs: Cute But Not as hypoallergenic as Advertised, Study Finds 

Dr. Karen Becker: The Allergy-Free Dog: Real or a Myth

Portuguese Water Dogs may be considered a lower-dander dog, but they still produce no fewer allergens than their shedding counterparts.