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Good Dog: Studies & Research
Genes Underlying Social Behavior in Dogs
The same genomic regions affect human social behavior

The remarkable social abilities of dogs include the many ways that they are able to interact with humans. Dogs seek out humans for food, companionship, assistance and information. They have evolved these social skills throughout their recent evolutionary past because of the advantages of communicating and cooperating with people. Genetic changes in the domestic dog over thousands of years are the source of these behavioral changes, but there remains a lot of variation in both canine genetics and canine social behavior.

A recent study (Genomic Regions Associated With Interspecies Communication in Dogs Contain Genes Related to Human Social Disorders) investigated behavioral and genetic variation in hundreds of Beagles with similar upbringing and similar previous experiences with humans. Researchers studied the dogs’ social behavior by presenting them with an impossible task. Dogs were given a container that held three treats, but only two of them were accessible to the dog. The third treat was impossible for the dog to obtain. Using video, researchers quantified the time dogs spent looking at the people in the room with them, approaching them, and being in physical contact with them. Different dogs showed different tendencies to seek human interaction when they faced an unsolvable problem.

To investigate possible genetic sources of this behavioral variation, the scientists used a process called GWAS (Genome-Wide Association Study). Basically, this means that a large number of parts of the entire DNA of each dog were examined to discover potential genetic variants that were associated with the social behavior. This study shows a strong genetic aspect to differences in human-directed social behavior by dogs. Researchers found multiple sections of DNA that were associated with differences in social behavior. In some cases, specific alleles (gene variants) were strongly associated with the tendency to seek out humans for physical contact.

Interestingly, the genes associated with variation in dog behavior in this study have been found to be related to various behavioral issues and social behavior complexes in humans. Specifically, autism, bipolar disorder and aggression in adolescents with ADHD (Attention Deficit and Hyperactivity Disorder) are all variations in human behavior whose genetic contributions come at least in part from the same areas of DNA that influence human-directed social behavior in dogs. This suggests that dogs may be an appropriate and valuable model for studying these aspects of social behavior in people.

 

Good Dog: Studies & Research
Premature Graying in Dogs
New study shows links with anxiety, impulsiveness and fear

We know that premature gray hair in people is a result of a variety of influences. Many parents swear that their kids are making them go gray. Before and after pictures of U.S. Presidents show an astounding increase in gray hair in eight—or even four—years. Of course, genetics is also known to play a role, as is disease. A recent study called “Anxiety and impulsivity: Factors associated with premature graying in dogs” in the journal “Applied Animal Behavior Science” suggests that premature grayness in dogs may be correlated with a number of factors, including some with emotional associations.

Their results are based on a study of 400 dogs in the age range of 1-4 years who were recruited with flyers at veterinary clinics, dog shows and dog parks. Each dog was photographed from the front and from the side so that the degree of graying on their muzzle could be assessed. They were scored 0 = no gray, 1 = frontal gray, 2 = half gray and 3 = full gray. Additionally, their guardians filled out a 42-question survey. Data on anxious behaviors, impulsive behaviors, fears, size, age, sex, number of dogs and cats in the household, time spent unsupervised outdoors, whether they were spayed or neutered, medical issues and participation in organized sports or activities were collected.

Researchers found an association between graying on the muzzle and anxious behaviors, impulse behaviors, fear of loud noises, unfamiliar people and unfamiliar dogs. The extent of grayness was positively correlated with age, and female dogs were more gray than male dogs. There was no link found for premature grayness with size, being spayed or neutered, medical problems (which were rare in the sample), reactions to thunderstorms, fear of unfamiliar places, number of dogs or cats in the household, time spent outside unsupervised or being involved in organized activities.
 

Dogs were only included in the study if it was possible to determine how gray their muzzles were. (White dogs and those with merled coloring didn’t make the cut, causing 43 dogs to be excluded from the study.) The people who evaluated the photographs were not the same people who had any knowledge of the questionnaires, which prevents accidental bias in assessment of the degree of graying. The survey was designed so that guardians were unaware of the purpose of the study. (They were simply told it was a study involving dog lifestyle.) In addition to questions that assessed the factors of interest in the study, there were so-called distractor questions to prevent people from biasing their answers based on what they thought researchers were investigating. Distractor questions included “Does your dog have hind limb dew claws?”

This research adds to our understanding of premature graying in dogs, and what’s most exciting about that is the possibilities it opens for helping dogs. Being anxious or fearful and struggling with impulse control are hard on dogs, and any help dogs receive for these issues can be beneficial. If premature graying provides a tip-off to professionals that these issues may be present, intervention may be more likely to happen and to happen faster. If behaviorists, veterinarians, trainers and other dog professionals know that a gray muzzle in a young dog may indicate that the dog suffers with these issues, perhaps they will more thoroughly assess them, or refer them to other people for evaluation. It’s just another way that people can potentially make life better and easier for many dogs.

Do you have a dog who has gone prematurely gray? If so, do you think anxiety, impulsivity or fear is an issue for your dog?

Good Dog: Studies & Research
Does Your Dog Make You More Attractive?
Animal Attraction
Men with Dogs -- Does Your Dog Make You Attractive?

The saying, “Love me, love my dog” implies that your dog is a problem—something negative in the whole package of You. Could anything be more ridiculous? While it’s easy to assume that our dogs make us more lovable and even more desirable (I mean, really, how could it be otherwise?), is there any evidence for this point of view?

The answer is yes! Multiple scientific studies—extensions of research into dogs’ many social effects—have concluded that dogs enhance human attractiveness. Scientists have known for some time that people are more attentive to and socially engaged with those accompanied by a dog than those who are not. We also know that bystanders are more helpful toward people with dogs. Other studies have extended our understanding of the canine influence on human social activity by investigating more personal, intimate types of behavior in the areas of courtship, dating and romance.

Pick-up Lines

In one study, having a dog with him enhanced a man’s success when he asked women out. In this experiment, the man asked 240 women for their phone number— 120 times while accompanied by a dog and 120 times without one. He followed the exact same script whether the dog was with him or not.

The difference the dog made in his success rate was astounding. When he gave his pitch without a dog, 11 out of 120 women (9.2 percent) were sufficiently charmed to give him their number. When he was with a dog, 34 out of 120 (28.3 percent) complied with his request. With a dog, his success rate was three times as high. Never mind a wingman— if you want to meet someone, you need a wing-dog!

Studies have shown that people’s helpfulness and social interactions are prompted most strongly by light-colored dogs and puppies. An adult black dog was part of this experiment; researchers speculated that if the man had asked women for their phone numbers while accompanied by a light-colored puppy, his success might have been even higher. (Guéguen and Ciccotti 2008)

Why do dogs (of any kind) increase our appeal? To most dog lovers, explaining how dogs can make someone more attractive is pretty straightforward: people are more attractive if they have dogs because they have dogs! Quite simple —also quite circular. As it happens, there are a number of other, more satisfactory explanations.

Many people report that those with dogs seem safer, friendlier and more approachable; by being a conversation starter, the dog may also ease social awkwardness.

Interacting with companion animals can result in changes in our oxytocin and other hormone levels, and that may affect the opinion others have of us as well. Those who feel a rush of oxytocin in the presence of a dog may transfer the warm, fuzzy feelings to the person with the dog. So, dogs may make people attractive by prompting emotions that are extended to them by association.

This may not be good for our ego, but it can still be good for our love life!

Does This Dog Make Me Look Cute?

Another study surveyed 1,210 people on Match.com who owned pets—both cats and dogs—to learn if and how pets influenced their views about potential dates. One of the main findings was that dogs had a greater positive impact on the perceived level of attractiveness than did cats. (Gray et al. 2015)

Interestingly enough, there was also a gender component. The study concluded that dogs make men attractive to women to a greater degree than they make women attractive to men. Women were more likely to find someone attractive because they had a dog, and were also more likely to find a photo of a dog in an online dating profile a turn-on. Not surprisingly, more men than women ’fessed up to using a pet to attract a potential date. (I know of no studies investigating how dogs affect attractiveness between members of the same sex, but it would be intriguing to see what patterns emerge once that area has been explored.)

Compelling biological forces suggest the reasons for this gender difference, and there’s a large body of work on the subject. The basic theory is that, because women must commit a large amount of energy and effort to produce offspring (pregnancy and often greater caretaking responsibilities for the children), they need to be more selective about who they choose as a mate. Men, biologically speaking, are capable of producing lots of offspring with a minimum of, um, effort, so they can afford to be less discerning in their choices.

Of course, there are many exceptions, and in today’s world, the division of child-care responsibilities is often more equitable than in the past, but our evolutionary heritage still influences our behavior. Women are often attracted to men who have something to offer to potential offspring.

Having a pet may be a plus for several reasons. The expense of a pet may be a variation on finding a man in an expensive car attractive. If it demonstrates wealth, it could be appealing, since a lot of evolutionary research suggests that females prefer males with substantial resources to devote to offspring. The social skills observed when a man interacts with his dog may also add to his allure. Just like men with resources to share, those capable of emotional commitment and those with strong parenting skills are more likely to contribute to the successful raising of children. Dogs can enhance perceptions of all of these qualities.

Although the effects of having a dog were different for the two groups, the majority of men and women surveyed said that finding out that a date had adopted a pet made that person seem more attractive. (Cat guardians were less likely to feel this way than dog guardians.) As everyone in this study was a pet guardian, the increased attractiveness of someone with a pet may simply reflect our natural inclination to like people with whom we have things in common.

The youngest people in the survey— those in their 20s—were more likely than members of any other age group to express an attraction to someone because of a pet. They were also more likely to judge a date based on that person’s reactions to their own pet than were members of other age groups. Perhaps being a pet guardian makes these younger men and women seem more grown-up, mature or responsible, which could be a plus for younger people.

Another explanation for this strong age effect is the growing trend toward considering dogs to be members of the family. An increasing number of people describe their dogs (and cats) this way, and it’s possible that dogs influence mate choice by revealing a person’s emphasis on family. Compared with older people, who may be new to the concept or may never have fully embraced it, the youngest people in this study may have always placed this level of importance on their pets.

As it happens, Bark readers of all ages seem to be more likely than the general population to consider dogs as family members. In reply to a blog post asking about this, two-thirds of the answers used words that implied familial relationships: dogs were their babies, or they were their dogs’ moms and dads.

Dad or Cad?

Another study warns women to be aware of how dogs influence their views. Men can be attractive because they seem romantic, caring and interested in long-term attachments; in other words, they would make good dads. Another type of man is more of a cad—dangerous, exciting and into chasing women. Women are often attracted to cads for short-term relationships and to dads as long-term partners, but dogs can interfere with that classification.

Women taking part in this study were provided with descriptions of both cadlike and dad-like men. They said that overall, they preferred to marry the dads, but many expressed an interest in shortterm affairs with the cads. These same characters were then described to women with only one detail changed—they were now all dog guardians. Dogs made both dads and cads more attractive, but the difference was greater for the cads. In fact, if cads had dogs, they were even more appealing than dads with dogs.

Dogs appear to supply cads with the perfect combination of traits; attractive, exciting cads seem to have had their bad qualities erased by having a dog. The potential for manipulation is obvious: a man exploiting the shortterm cad-like strategy can block negative perceptions of his style by having a dog. As the authors of the research study write, “Thus, a cad with a dog is especially attractive to women, as they may believe they are getting the best of both worlds.” (Tifferet et al. 2013)

It’s wonderful to know that dogs can make men, and, to a lesser extent, women, more attractive. Now, if only scientists could find evidence that dog hair has the same powerful effect!

Good Dog: Studies & Research
Improving Your Dog’s Learning
Does playing after training sessions make a difference?

Many people know that going to sleep after studying helps consolidate the information and commit it to long term memory. (It works out beautifully if the subject was putting you to sleep anyway!) For dogs, a different approach may be worthwhile. Researchers conducted a study in dogs called “Playful activity post-learning improves training performance in Labrador Retriever dogs (Canis lupus familiaris)” and concluded that physiological arousal—in the form of play—following training has a positive effect on learning in dogs.

The subjects of the study were all Labrador Retrievers, which allowed the researchers to make sure that differences between breeds did not influence their results. The dogs were trained in a choice task between two objects that looked and smelled differently. Training took place in sessions of 10 trials with short breaks to walk around outside or rest in a waiting area in between each session. Dogs were considered successful at the choice task when they chose the right object eight or more times in two consecutive trials of 1O.

Once dogs reached this level of success, they either rested for 30 minutes in the presence of their guardian and one of the researchers, or they were active for 30 minutes. Specifically, that activity consisted of 10 minutes of walking on leash, then 10 minutes of off leash play (fetch with a ball or with a disc or tug, depending on the dog’s preference), then 10 more minutes of walking on leash. The dogs in each group (rest or activity) were monitored for salivary cortisol levels and heart rate to confirm that their states of physiological arousal were different. (They were.)

The following day, all of the dogs were tested again to see how many trials it took them to relearn the task. The difference between the two groups was remarkable. The dogs who walked and played after training took an average of 26 trials to relearn the task. The dogs who rested after training needed an average of 43 trials to reach that same level of success. The differences could be a result of chemical changes in the brain.

The brain is affected by chemicals that influence memory, whether those chemicals are naturally produced by the body or given as a drug. Various studies have shown that hormones and drugs that induce high arousal can have positive effects on memory if the brain is exposed to them after training.

The results of this study provide further evidence that arousal following training can be beneficial, since dogs in the active group were more highly physiologically aroused than dogs in the rest group. However, I’m not convinced that the data show that play itself is the key factor that caused the difference between the two groups in the study. Perhaps the walking part of the post-training activity played a role, and it may be that any form of exercise could be beneficial following training.

I hope researchers conduct studies in the future to investigate whether it is truly the play itself that improves learning in dogs. I would love to know if playing during training (as opposed to after) enhances dogs’ learning, whether because of physiological arousal, or simply because it might be easier to learn when having fun.

Whether play is the cause of the difference between the two groups or not, I’m definitely in favor of playing with dogs after training sessions. It provides a mental break for dogs after the hard work of training. Most dogs love training, and the fun of play prevents a negative feeling about the end of a session. Both training and play can strengthen relationships between people and dogs and doing them back-to-back may be especially powerful. I often play with dogs after a training session, and if that enhances their training because of positive effects on memory, that’s another bonus.

Do you play with your dog after training sessions?

Good Dog: Studies & Research
When a Child’s Pet Dies
New research explores how kids respond

The dogs of childhood are important beyond imagination. Kids describe them as their best friends and as their siblings. Many children view themselves as the primary recipient of their pets’ affections. Often, young people see little difference between the close connections they have with the human members of their family and those they share with the non-human ones. Because of most animals’ shorter lifespans, though, many kids must face the death of a dog, cat, or other pet. Their emotional response to the loss of a pet and what they say about the experience is the subject of the dissertation research and further study by Joshua J. Russell, PhD.

According to Russell’s research, children’s responses to the death of a pet are predictable in some ways. Kids had a much easier time dealing with the death of a pet if the animal reached an age where death was expected. Early deaths, especially unexpected ones, made it much harder for children to come to terms with the loss. Russell points out that kids have a strong sense of fairness related to whether their animals lives as long as they were “supposed to” or whether they died before that. Acceptance was easier for kids whose pets lived far into the normal lifespan for the species. Generally, kids understood that hamsters and fish don’t live very long, but many struggled to understand that our dogs, cats and rabbits will often die before we do. When a death happened because of an accident, it was especially difficult for kids to cope.

Many children who Russell interviewed felt that euthanasia was the right thing to do if a pet was suffering. Kids were split in their views about getting another pet after the death of another. Some felt that it was disloyal to the previous pets and their relationships with them. Others felt certain that they would feel better if they got a new pet and that the new relationship didn’t have anything to do with the old one.

It’s always difficult to deal with the grief of losing dogs, and it hurts my heart (a lot) to consider the pain that it causes children. It’s no fun to think about the way it feels for children to lose a pet because we can empathize all too well, no matter how old we are.

What do you remember about what is was like when a dog from your childhood died?

 

Wellness: Food & Nutrition
GMO: Are genetically modified crops safe in your dog food?
A vet speaks out on genetically modified pet food.

Most dogs now dine on some type of genetically modified (GM) food, often in the form of corn and soy in their kibble. As these ingredients increasingly enter the food supply, we have one more reason to wonder if our shopping choices might be harming our pets.

More animal feeding studies are needed, experts say, and a recent long-term, peer-reviewed report points out why. It found that a diet of GM corn and soy led to higher rates of severe stomach inflammation in pigs, which are physiologically similar to dogs.

Robert Silver, DVM, a Boulder, Colo., holistic vet, tackled the issue earlier this year when he presented his paper, “Genetically Modified Food and Its Impact on Pet Health” at the American Holistic Veterinary Medical Association conference in Kansas City, Mo. Why did he choose this controversial topic, one that few vets even acknowledge?

Silver—a pioneer in the field of holistic veterinary medical practice—says he was inspired by a seminar he attended in Boulder on GM foods and human health. The speakers included Don Huber, a Purdue University professor, and activist Jeffrey Smith, who discussed problems, including reproductive difficulties, that have occurred in livestock fed GM crops.

“I found this seminar mind-opening,” says Silver, the lone vet in attendance. “I had always believed the PR about GM foods—that they are going to feed the world and are a good outcome of our genetic technology.”

The Food and Drug Administration, which regulates the safety of GM crops consumed by humans and animals, considers most GM plants “substantially equivalent” to traditional plants and “generally recognized as safe.” Their regulation involves a voluntary consultation process with the developer before products are brought to market.

Smith, founder of the Institute for Responsible Technology, disagrees. On its website (responsibletechnology.org), he warns that “nearly all GM crops are described as ‘pesticide plants.’ They either tolerate doses of weed killer, such as Roundup, or produce an insecticide called Bt-toxin. In both cases, the added toxin—weed killer or bug killer—is found inside the corn or soybeans we consume.”

Silver says that while “allergies, GI problems, increased risk of cancer, neurodegenerative conditions” and other ills could all be, in part, related to GM foods, “there is no objective evidence of this yet” in dogs. “However, all vets will agree that there has been an uptick in [these diseases] in the past 10 to 20 years.” The advent of GM foods in the 1990s “fits into this timing of disease increases,” he says.

His presentation referred to studies that raise doubt about the safety of biotech crops, such as one reported in 1996 in the New England Journal of Medicine, which found that genes inserted into crops can carry with them allergenic properties.

Silver says that genetic modification introduces foreign proteins that may encourage allergies, and the widely planted Bt corn, which makes its own insecticide, “could possibly cause leaky gut, the gateway to chronic disease.” Corn is a major component of most commercial pet foods. “The big problem with commercial foods is that they are manufactured at high temperatures and pressures,” which alters them and makes them “potentially more allergenic.” And commercial foods contain industrial ingredients that are “more likely to contain GM and herbicide contaminants.”

A study published last year found that GM crops engineered to withstand the toxic herbicide Roundup must now be doused with even more herbicide, since weeds have also developed resistance to it. Residues of these chemicals on crops can find their way into pet food.

A 2013 study published in the science journal Entropy reports that the heavy use of Roundup could be linked to Parkinson’s, autism, infertility and cancers. It goes on to report that residues of Roundup in food can interact with, and enhance, the damaging effects of other environmental toxins. “Negative impact on the body is insidious and manifests slowly over time as inflammation damages cellular systems throughout the body,” the study’s researchers say.

According to Silver, heightened sensitivity to dietary ingredients “is probably what we are seeing with GM foods. It is of concern that this may be driving the increase in GI problems in pets.” Although gluten probably does account for some problems with grain consumption, “I think that grain-free diets, if they are also soy free and contain protein from animals not fed GM crops, can help many dogs, due to being GM free—and not due to some allergy or gluten issue.”

To a holistic doctor, food is medicine, and Silver strongly recommends home meal preparation from individually sourced ingredients to avoid feeding GM ingredients, especially to pets who have other health problems. “I am truly a holistic practitioner in that I believe an ounce of prevention is worth a pound of cure.”

References
Carman, J., et al. 2013. A long-term toxicology study on pigs fed combined genetically modified (GM) soy and GM maize diet. Journal of Organic Systems 8 (1): 38–54.

Benbrook, C.M. 2012. Impacts of genetically engineered crops on pesticide use in the U.S.—the first 16 years. Environmental Sciences Europe 24: 24.

Ordlee, J., et al. 1996. Identification of a Brazil-nut allergen in transgenic soybeans. The New England Journal of Medicine 334: 688–692.

Samsel, A., and S. Seneff. 2013. Glyphosate’s suppression of cytochrome P450 enzymes and amino acid biosynthesis by the gut microbiome: Pathways to modern diseases. Entropy 15 (4): 1416–1463.

Good Dog: Studies & Research
Genome of Sardinian Sheepdog Provides Insight into Human Migration Patterns
Photo by Stefano Marelli

The discovery of one of the last pure landrace dog breeds, the Sardinian Sheepdog (Cane Fonnese, Fonne's Dog) was celebrated by scientists in the October 11, 2016 issue of the journal Genetics.

The study revealed that the large flock guardian dog travelled the same ancient migration routes as the Sardinian people. And like their people the dog's genetic signature remains distinctly isolated.

A landrace is a regional type of domestic animal that over a long period of time has adapted to its purpose and environment through unregulated selection for behavior. Landrace dogs were common up through the early 1800s, but most disappeared as a consequence of cross breeding with dogs introduced by travelers.

The Sardinian Sheepdog is a breed because it's been created within an isolated population of animals. Sardinian shepherds allowed only their best working dogs to reproduce.

What's appealing to scientists is that the dog remains uncontaminated by modern artificial breeding practices, resulting in a robust genome. Sardinian dogs don't all look the same, but all have in common a high drive to guard sheep.

Sardinia is the second largest island in the Mediterranean Sea, just south of Corsica. The island was populated in multiple waves of people as far back as the upper paleolithic.

The study also revealed that the Sardinain Sheepdog originated from sight hounds developed in the near and middle east as well as large mastiff-like sheep guarding dogs from an area around Hungary.

Their genomic map mirrors human migration. Just like their dogs, the people of Sardinia derive from Hungary and the middle east.

Science Daily offers a reader-friendly description of the significance of the study: "Just as Sardinian people have long provided a wealth of genetic insights to scientists, the canine natives are an example of an isolated population that could prove a powerful resource for finding genes that influence health and behavior."

Read more about Cane Fonnese, landrace animals, and Sardinia.

Good Dog: Studies & Research
Studying Our Relationships with Dogs
How to approach future research

“Yes, that’s just how it is with my dog, too!”

“Everybody knew that before reading about it.”

“I figured I wasn’t the only one who felt that way about my dog.”

“Obviously.”

These are common responses to stories about the many research papers investigating the relationship between people and dogs. Most of us read the latest scientific findings with a great sense of happiness and validation. Our relationship with dogs is very much like our relationship with our children? Yep. Our dogs consider their guardians to be extra special and emotionally important? Whew, thought so. Our attachment to our dogs provides us with many benefits? Duh. Being a helicopter parent does not cause the damage to fur kids that it can to human kids? Yay!  Gazing into our dog’s eyes can enhance the feelings of true love between us? Awww.

It’s exciting that there has now been enough research into attachment between people and dogs and the bonds they have for one another to prompt a review paper to suggest where to go from here. The recently published “Measuring dog-owner relationships: Crossing boundaries between animal behaviour and human psychology ” summarizes what we know and discusses what should be studied next as well as how. That means we can all happily anticipate more revelations that will further confirm the many details about what we know: Humans and dogs are close in wonderful ways that benefit us both. In the introduction to the paper, the authors say, “In this review, we propose that the next step in anthrozoology [study of interactions between humans and other animals] research is to use all the potential information within attachment theory, to reveal whether or not different types of relationship styles exist among different dog-owner dyads and how they might be identified. Furthermore, we give suggestions for which factors may contribute to the development of different attachment styles in dogs, hence deserving more attention in future studies of the dog- human relationship.” What this means is that there is a wealth of information about relationships between humans and the styles of connection that people have with one another that can be used to inform future research on the ways that dogs and people forms bonds to one another.

Some suggestions that these authors have are to focus on both dogs and people simultaneously rather than just one side of the relationship. They also recommend investigating physiological as well as behavioral responses to situations (such as separation and reunions) that are often the focus of attachment studies. They encourage addressing both the attachment style of individual dogs and the caregiving style of individual people to help pairs avoid any conflicts that have plagued them in the past and to help them form the best, most positive relationships in the future.

What are you most interested in knowing about the science of your relationship with your dog?

Good Dog: Studies & Research
Do Dogs Ignore Bad Advice?
A study investigating this question is problematic

Dogs are inclined to follow our lead in many ways, but they don’t go overboard if it does not serve their interests, say the authors of a new study. If people give dogs bad advice, they figure out that it is worth ignoring, according to a new study in the journal Developmental Science. Let’s look into how they arrived at this claim, which I don’t think is supported by the data.

The researchers were investigating whether dogs (and dingoes) would imitate the way people showed them how to get food out of a puzzle box even when there was an easier way to do it. Only one step was required to reach the food, and that was lifting the lid to a box. As part of the experiment, humans added an extra, unnecessary action to the process by pulling a lever that did nothing, and then lifting the lid of the box.

Both the dogs and the dingoes quickly learned to skip the step with the useless lever and just open the box to get to the treat inside. In other words, it looked like they ignored the useless instructions from the humans. This behavior differs from human children, who tend to perform all the steps they have been shown even when some of them are unnecessary. That behavior is called “overimitation” and the uncritical copying of the behavior they observe may allow kids to minimize the amount of trial-and-error learning they must do.

The dogs and the dingoes observed humans opening the box, and were then repeatedly given the opportunity to open the puzzle box. Over time, as they gained experience with it, they were less likely to use the lever. The experimenters consider this evidence that both species learned that pulling the lever was an unnecessary step for opening the box, even though they saw humans doing it. I agree that the data support the idea that they learned that the lever is irrelevant. I just don’t think that observing the humans pull the lever made any difference, and that’s because this study does not find any evidence that dogs imitated the humans at all.

In addition to the experiment in which subjects observed humans pulling the irrelevant lever, there were also a series of trials (with a different set of dogs and dingoes) in which they were presented with the puzzle box without any opportunity to observe a human opening it. In that experiment, the dogs and dingoes were solving the puzzle without having seen anyone else open it, so they were doing it completely on their own. The authors write that, “dogs were equally likely to use the irrelevant lever, regardless of whether they witnessed a demonstration (in Experiment 1) or not (in Experiment 2).

They point out that there was no evidence that dogs were more likely to copy the humans’ actions than the dingoes were, but what’s just as important is that there was no evidence that the dogs were copying humans at all. Therefore, I don’t think that their conclusions about dogs and overimitation hold water. They would first need to show that dogs copy any human behavior, which they do not do, in order to then test whether dogs copy irrelevant human behavior.

There was one interesting conclusion from this study, though it has nothing to do with imitation, social learning, or human influence on dogs’ actions. Evidence from this study, as well as previous research, indicate that dingoes solve problems more quickly and with greater success than dogs. In Experiment 3 in this research paper, a different puzzle box was used. Pulling the lever was an essential step in opening this particular puzzle box. In this experiment, both dogs and dingoes did pull the lever in order to access the treat inside. When compared to the rates of pulling the lever when it was pointless, dingoes showed a greater change in their behavior. That is, they were more likely than dogs to pull the lever only when it was relevant, unlike dogs, who pulled it quite often even when it was not an essential part of the box-opening task.

Questions about the possibility of overimitation in dogs are extremely interesting, and I want very much to know more about this behavior, which I don’t think was adequately addressed by this study.

Good Dog: Studies & Research
Young Dogs, Old Dogs and New Tricks
The role of age in learning, memory and logical thinking

Old dogs CAN learn new tricks, but the way that they learn may be different than when they were younger. So concludes a recent study called “Aging effects on discrimination learning, logical reasoning and memory in pet dogs”. The study was conducted on 95 pet Border Collies who ranged in age from 5 months to over 13 years old. Researchers purposely chose dogs of the same breed in order to minimize any differences in performance that were unrelated to age.

Starting out with a spoiler, older dogs did worse than younger dogs on one of the tests, they did better on a second test, and there was no effect of age in the third test.

For the first test, dogs were trained to associate four images on a touch screen with a positive experience—receiving a treat. So, if the dogs touched these images on the screen, they received a treat. Another four images were associated with a time out, meaning that touching any one of them resulted in no opportunities to touch images for a brief period of time. After being taught these associations, dogs were tested with a pair of images that always included one randomly selected “treat” image and one randomly selected “time out” image. Sessions consisted of 30 tests with a pair of images. Dogs were considered to have mastered this task when they chose the right image 20 out of 30 times for four out of five sessions in a row. There was a linear relationship between age and the number of sessions it took dogs to learn this task, meaning that younger dogs learned it faster than older dogs.

In the second test, dogs were again shown a pair of images on the touchscreen, but only one of those images was one that the dog had seen before. In each case, the familiar image was one that the dog had learned had a negative association because it led to a time out if touched. The dogs could therefore make an inference that the unfamiliar image was the correct choice and would lead to a treat if touched. (These trials were interspersed in sessions that included pairs of images just as in the first test in which both images were familiar to the dogs.) In this experiment, the older dogs were, the more likely they were to choose the correct image, meaning that older dogs were better at solving this puzzle than younger dogs.

The final test in this experiment looked at long-term memory. Dogs were tested at least 6 months after the other parts of the study were completed to determine how well they retained what they had learned. When presented with pairs of images just as they had been in test one, over 90 percent of the dogs performed better than chance level (at least 22 correct out of 32) and there was no effect of age on the success rate.

This study shows that there are differences in cognitive abilities between older and younger dogs, but not that dogs of certain ages have better abilities than dogs of other ages. The way that age affects performance depends on the specific task dogs are asked to do.

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