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News: Karen B. London
Egyptian Dog Mummy Had Parasites
Those little pests are nothing new!

Mummified dogs are not a new archaeological discovery, but finding bloodsucking parasites on them is. Over 400 dog mummies unearthed from the El Deir excavation site in Egypt have been found, and one young dog among them was infested with a number of parasites that have been preserved.

There were over 60 ticks found on this poor dog and there was one louse, too. The scientists who found this dog suspect that a tick-born disease that kills red blood cells was probably responsible for the death of this dog at such a young age. Besides the ticks and the louse, remains of two types of fly larvae were found on it, suggesting that the dog’s body had time to attract carrion flies prior to being mummified.

Mummifying animals was common in ancient Egypt. It was done to provide food and companionship for people in the afterlife and to make sacrifices to the gods, yet nobody is sure of the reasons for the dog mummies at El Deir. It is unclear if they had specific human guardians or how they died. Perhaps they were purposely bred to be sacrificed as cats commonly were, but we just don’t know.

Scientists involved with this excavating project are exploring questions about the source of the dogs. They are also hoping to find more parasites on the dog mummies in order to investigate the origin and spread of diseases and to deepen our understanding of the role of parasites in the history of the species.

Evidence that ancient dogs suffered from ticks, lice and other ectoparasites is prevalent in ancient writings such as those of Aristotle, Homer and Pliny the Elder, but this is the first archaeological evidence that corroborates those texts. It’s certainly no surprise that dogs living a couple of thousand years ago faced the danger and nuisance of ticks and lice. It would be astounding if it were a recent development in the lives of canids, but it’s still interesting to have such concrete evidence.

News: Karen B. London
Dog Lifespans by State
Where are dogs living longest?

It is hard to decide which of the many wonderful qualities of dogs is the best one, but it’s easy for me to say what is the worst thing about dogs: They don’t live long enough. We all wish dogs lived longer and most of us are hungry for information about which factors may give us more time with our dogs. It’s possible that where our dogs live is one such factor.

A state-by-state analysis of dog lifespan shows Montana and South Dakota at the top with dogs living an average of 12.4 years. Other states with long-lived dogs include Oregon, Colorado and Florida where the dogs are typically living over 11 years. In contrast, Mississippi and Alabama have an average lifespan of just over 10 years.

These data come from Banfield Pet Hospital and only include those states in which they have facilities, which means that Wyoming, North Dakota, Maine, Vermont and West Virginia are not included. It also means that the data may only reflect the specific dogs seen in their practices rather than fully representing each state’s dogs.

However, there are a number of reasons that lifespans may vary from state to state. These include nutrition, exercise opportunities, rates of spaying and neutering and the types of disease prevalent in the area. The breeds and sizes of dogs that are most popular in those states may matter, too.

News: Guest Posts
Dog Drinking: An Acrobatic Tongue Act

If you live with a dog, then you are familiar with this sound.

Unlike barks, growls and howls — dog sounds that easily take center stage — a dog lapping up water is background, white noise. Dog drinking attracts little attention until you unexpectedly step in a puddle of slopped-over water while wearing socks.

A closer look reveals there is nothing commonplace about how dogs drink. Instead, to ingest liquids, the tongue seems to perform almost acrobatic feats. Slow-motion footage of dogs lapping up water shows that the tongue curls backward to create a spoon shape. The below video from of The Secret Life of Dogs, a Nat Geo WILD special that premiered Sunday, August 25, hints at the intricacies of how dogs drink.

 

From the above clip, it could appear that by curling the tongue backward and filling the spoon-shaped tongue with water, dogs drink by scooping, or spooning, liquids into their mouths. But a paper published by Crompton and Musinsky in Biology Letters in 2011, finds there is more to the story.

While dog tongues do assume a spoon-shaped position while drinking, much of that liquid falls out. Using high-speed and x-ray video recordings of a dog lapping up a colored liquid, instead of clear water, the researchers could see that the tip of the dog’s tongue was actually drawing a column of water up into the mouth, and this column of water is what dogs are drinking. This observation is difficult to make from slow-motion videos of dogs drinking clear liquids like water. By taking x-ray video of a dog drinking a dark liquid, in this case a mixture of milk and barium, Crompton and Musinsky could see that dogs draw up liquid by the tip of the tongue, and the tongue then traps previously lapped water onto the roof of the mouth so the dog can bring more water in without losing what it already has.

Ultimately, the researchers found that dogs use the same drinking technique as cats. This might be surprising because dogs make such a mess while drinking, and cats seem to emulate the daintiness of royalty, but dog tongues dive deeper into liquids thereby giving off more spray.

The researchers concluded that dogs and cats share the same basic mechanism for drinking: “adhesion of liquid to the tongue rather than ‘scooping’ by the tongue.” I’ll drink to that.

 

Additional Reading and References

Crompton and Musinsky. 2011. How Dogs Lap: Ingestion and Intraoral Transport in Canis familiaris. Biology Letters 7, 882–884.
Reis et al. 2010. How Cats Lap: Water Uptake by Felis catus. Science 330 1231–1234.
Young. Dogs Do Drink Like Cats After All. Not Exactly Rocket Science. May 24, 2011.

About the Author

Julie Hecht, MSc, is a canine behavioral researcher and science writer in New York City. She writes a behavior column for The Bark. She would really like to meet your dog. Follow on Dog Spies at Facebook and Twitter @DogSpies | DogSpies.com

This story was originally published by Scientific American. Reprinted with permission.

News: Guest Posts
What Do You Hear in These Dog Sounds?
All barks are not alike

AS YOU PROBABLY KNOW, your dog’s voice is not like a Bret Michaels concert, pumping out a shower of meaningless noise. Although your dog’s vocalizations might be unwelcome at times, those sounds carry way more information and meaning than any of the former frontman’s power ballads can ever hope to do. Well, maybe not as much as “Every Rose Has Its Thorn.”

In recent years, many studies have investigated the noises made by companion dogs. Now, you (yes, YOU!) can help researchers in a new study where participants listen to and rate different vocalizations. But first, what have we learned about dog vocalizations so far?

Time to Be All Ears

One major finding: dogs bark differently in different contexts, and it’s possible to tell the difference. Sophia Yin, DVM, MS, found that “disturbance barks” (e.g., barks in response to a stranger ringing the doorbell) sound different from “isolation barks” (when a dog is separated from an owner) as well as barks emitted during play. In each context, barks have specific acoustic parameters: where disturbance barks are “relatively low-pitched, harsh barks with little variation in pitch or loudness,” isolation barks are “higher pitched, more tonal and more frequency-modulated than the disturbance barks,” and play barks are “similar to the isolation barks except that they usually occurred in clusters rather than singly” (Yin, 2010 Blog Post). Instead of seeing barks as meaningless noise, pay attention. Banjo might be yipping because he’s alone, or he may have noticed that someone uninvited is climbing in through your second floor window.

Dog barks are full of information, but what about growls? Anna Taylor and colleagues at the University of Sussex studied growling and found that, unlike barks, many acoustic properties of growls recorded in a play and aggressive context did not differ. But aggressive growls were longer than play growls, and play growls had a shorter pause between growls.

While growls are thought to be associated with aggression, remember they can also appear during play, so consider growling in a larger context. Additionally, if you come across a situation where growling could be associated with aggression, don’t freak out. Jolanta Benal, CPDT-KA, CBCC-KA and author of The Dog Trainer on Quick and Dirty Tips, reminds: if you punish a dog for growling, you are essentially punishing a dog for giving a warning. Growling is a form of communication related to emotional or inner states in a particular context. If you want to decrease growling, think about what’s prompting the growling. The growling itself is not a problem.

Many high-profile dog vocalization studies were developed by Péter Pongrácz, Csaba Molnár and Tamás Faragó of the Family Dog Project at Eötvös Loránd University in Budapest. In one notable study, dogs were placed in a room with a bone, and researchers played a recording of one of three growls from a different dog. Dogs responded to the “this is my food” growl by backing away from the bone, and dogs for the most part ignored the “go away stranger” and the play growl because those growls were not relevant to the bone. All growls are not the same, and dogs know it. So let’s try to get on the same page as them.

While we are learning about the noises coming from dogs’ mouths, we still have a way to go. I recently spoke with Monique Udell, an Assistant Professor at Oregon State University and a canine researcher, for an article on dog vocalizations for The Bark magazine (view article here). As Udell pointed out, “Vocal behavior in other species has received a lot of detailed attention. In birds, we’ve looked down to the note sequence and explored tiny variations. Vocalizations are such a prominent feature of dogs, and there is a lot to learn.”

Listen! You Can Help!

Now, back to what YOU can do to advance the science of vocalizations from the comfort of your couch. Tamás Faragó, now a postdoctoral researcher with the MTA-ELTE Comparative Ethology Research Group in Budapest, is exploring how humans perceive emotions in vocalizations. The study asks human subjects (like you!) to listen to and rate different vocalizations on a chart based on how aroused you think the vocalization is and whether you think it’s positive or negative. I promise you will not hear a single note of “Every Rose Has Its Thorn.” Okay, only if you want to. The whole survey takes about a half hour, and as you go along, you’ll you get the swing of it. Check out the details below to participate.

You Can Participate in a Study of the Emotional Content of Sounds

Participants: Anybody in any country

Time commitment: Approximately 30 minutes

Project type: Listen to and rate different sounds

Project needs: Computer with headphones or decent quality speakers

Survey website: http://www.inflab.bme.hu/~viktor/soundrating/index.html

So don’t just stand there. Listen!

Additional Reading

Hecht, J. Dog Speak: The Sounds of Dogs. The Bark Magazine.

Nova. The Meaning of Dog Barks.

Yin, S. Barking Dogs: Noise or Communication? Dr. Yin’s Animal Behavior and Medicine Blog. Monday, November 15th, 2010.

References

Taylor et al. 2009. Context-related variation in the vocal growling behaviour of the domestic dog (Canis familiaris). Ethology, 115, 905–915.

Faragó et al. 2010. ‘The bone is mine’: affective and referential aspects of dog growls. Animal Behaviour, 79, 917–925.

Yin and McCowan. 2004. Barking in domestic dogs: context specificity and individual identification. Animal Behaviour, 68, 343–355.

 

About the Author

Julie Hecht, MSc, is a canine behavioral researcher and science writer in New York City. She writes a behavior column for The Bark. She would really like to meet your dog. Follow on Dog Spies at Facebook and Twitter @DogSpies | DogSpies.com

This story was originally published by Scientific American. Reprinted with permission.

 

 

 

 

Wellness: Healthy Living
GI Involvement in Behaviorial Issues
Some Compulsive Disorders Point to the Gut
Dog looking away

Canine compulsive disorders (CCDs) take many forms and are generally considered to be behavioral issues. However, recent studies suggest that at least two of them—“excessive licking of surfaces” (ELS) and “fly-biting syndrome,” in which a dog appears to stare at something and suddenly snaps at it—may be related to underlying health issues. Both studies were conducted by researchers associated with the University of Montréal Veterinary Teaching Hospital.

The first set out to investigate surface-licking behaviors to see if there was a medical component: “The objectives of our prospective clinical study were to characterize ELS behavior in dogs and to examine the extent to which it may be a sign of an underlying gastrointestinal (GI) pathology as opposed to a primarily behavioral concern.”

Researchers looked at 19 dogs, 16 of whom exhibited this behavior daily. This group was compared with a control group of 10 healthy (i.e., non-ELS) dogs. Complete medical and behavioral histories were collected for all dogs. The medical evaluation revealed that 14 of the 19 ELS dogs had GI abnormalities; treatment of the underlying GI disorder resulted in significant improvement in a majority of dogs in the ELS group.

The second study examined seven dogs with a history of daily fly-biting behavior. As the researchers noted, “Fly-biting dogs are generally referred to neurologists or behaviorists because the abnormalities are often interpreted as focal seizures or as obsessive-compulsive disorder (OCD).”

As in the ELS study, these dogs were given complete medical examinations and were filmed to determine if the behavior was perhaps more prevalent after eating. The video analyses revealed a significant finding: all of the dogs demonstrated head-raising and neck extension, which can be an indicator of esophageal discomfort, prior to fly-biting.

All of the dogs in this study were found to have a GI abnormality, and one was also diagnosed with Chiari malformation (a brain/skull disorder). The dogs were treated for their medical conditions, and four had complete resolutions of the fly-biting behavior. The authors of this study concluded, “The data indicate that fly-biting may be caused by an underlying medical disorder, GI disease being the most common.”

As Marty Goldstein, DVM, observed in a post related to this research, “These studies don’t mean that primary obsessive/compulsive behavioral issues don’t exist, because they do … [But] if you have a pet with obsessive/compulsive disorders, don’t jump to psychoactive medications before exploring the use of food-allergy testing, changes in diet, and digestive enzymes and probiotics that can repair a damaged GI tract.”

News: Karen B. London
The Animal Behavior Society Conference
Many presentations featured dogs

Last week, the Animal Behavior Society conference was held in Boulder, Colorado and was attended by hundreds of scientists. Besides being the 50th annual meeting, this conference was notable because of the strong representation by people who study dogs or work with them in other ways.

I first attended an Animal Behavior Society conference in 1994 and I remember no talks or posters about our best friends. Most talks were about insects, fish, and birds, all of which have long been subjects of study in the field of animal behavior. Studying dogs was not respected at that time and many people considered that research on the species was not applicable to science in general because dogs didn’t have a natural habitat other than living with people. I hadn’t started working with dogs professionally yet, and my talk on my graduate research was called “Nest Site Selection by a Member of a Wasp-Wasp Nesting Association.” Oh, how times have changed.

At this conference, dozens of people presented work, whether applied or basic, about dogs, including 21 Certified Applied Animal Behaviorists, or CAABs. (The certification is available to people with PhDs who work in applied animal behavior and have a number of other qualifications. There are currently about 50 of us CAABs.) This conference had more presentations about dogs than any previous ones. There were a number of interesting talks and posters about dogs including:

Differences in social and cognitive behavior between congenitally deaf and hearing dogs

The black dog syndrome: Factors influencing difficulty of canine adoptions

Social bonds between humans and their “best friends”

Improving enrichment for shelter dogs by changing human behavior

Are dogs exhibiting separation related problems more sensitive to social reinforcement?

Do puzzle toys have long-term benefits on canine cognitive functioning?

Inter-dog aggression in the home environment: A behavior modification case study

A comparison of the cognitive development of adolescent dogs

Successful treatment of canine human-directed resource guarding with multiple triggers

I loved attending talks about a variety of species, but seeing how much change there has been in the scientific community’s views about dogs over the last 20 years made this conference extra special.

 

News: Karen B. London
Disagreement About Dog Domestication
Conflict among scientists who study it

Research about canine genetics and the domestication of dogs is an exciting area of study with many players, so it should surprise nobody that there is disagreement within the field. Multiple groups of researchers from around the world have compared the genomes of dogs and wolves. While they generally agree about the genetic changes that have produced differences between dogs and wolves, their conclusions about the domestication of dogs vary wildly.

The disagreement concerns fundamental aspects of the evolution of dogs such as where, when and why dogs evolved from wolves. So, the location, the timing, and the reason for domestication that various groups propose are not even close.

One group suggests domestication occurred around 10,000 years ago in the Middle East and that it was the development of agriculture around that time that was the catalyst for domestication. Another group claims that it happened around 32,000 years ago in the south of China and related to scavenging alongside the people living there. A third group narrows the time frame for domestication to between 16,000 and 11,000 years ago, and believes that the wolf population from which dogs arose is extinct, making it hard to determine the location of domestication. This third group believes that dogs became domesticated near hunter-gatherers rather than in the presence of an agrarian society.

Much has been made about the discord among scientists studying the domestication of dogs, but it’s hardly surprising. The cutting edge of science is always marked by strongly held opposing views. In the best situations, the intense disagreement among people working in the same field is a crucial part of making progress. Competing hypotheses are critical for the advancement of science. As people challenge each other’s views, all are spurred to study the subject more deeply and design experiments to investigate that which has been called into question. From the ongoing work, the conflicts are eventually resolved as some ideas fall by the wayside and others gain increased support from new data and discoveries.

Sometimes the conflict is cordial and in other cases, it can be very bitter. At this point, the scientists studying dog domestication say that though there is a certain amount of rivalry, they get along and enjoy talking with each other. That may be harder to maintain as people move to the next phase of research into dog domestication and seek to sequence DNA samples from ancient dogs and wolves. The availability of archaeological bone samples is extremely limited so there will be a lot of competition among scientists for both funding to conduct the research and access to the material necessary to do so.

In other words, we can expect a lot of fights over bones in the near future.

News: Karen B. London
Disadvantages of Pet Store Puppies
Unfavorable behavior compared to other puppies

In a study of over 6000 puppies, researchers found that the behavior of puppies purchased from pet stores was less desirable than the behavior of puppies obtained form noncommercial breeders. Specifically, there were 12 areas in which pet store puppies’ behavior was unfavorable compared with puppies from noncommercial breeders and two areas in which their behavior was similar. There were no behavioral areas in which the pet store puppies’ behavior was preferable to the comparison group.

In a recent study called “Differences in behavioral characteristics between dogs obtained as puppies from pet stores and those obtained from noncommerical breeders" used guardian observations of their dogs to compare the behavior between the two study populations. Observations were quantified using the Canine Behavioral Assessment and Research Questionnaire, which uses ordinal scales to rate either the intensity or frequency of the dogs’ behavior

The biggest differences between the two groups of dogs related to aggression with dogs from pet stores being far more likely to be aggressive towards their guardians, to other dogs in the household, to strangers, and to unfamiliar dogs. Among their other unfavorable comparisons with dogs from noncommercial breeders were that they were more likely to have house soiling issues, to be fearful, to have touch sensitivity problems, to be harder to train, and to have issues with excitability.

As a person who has long opposed the selling of puppies in pet stores for humane reasons as well as behavioral, it is with open arms that I welcome this objective study about the undesirability of this practice. It’s heartbreaking for me to think of all the people I have seen professionally over the years who have been emotionally devastated by the serious behavioral issues they have faced with a dog from a pet store. Of course, there are people who have lucked out and obtained a wonderful dog from a pet store, and I am very happy for such dogs and their people. However, it’s important to remember that overall, buying a dog from a pet store does not put the odds in your favor.

The authors of this study sum their research up with this important point: “Obtaining dogs from pet stores versus noncommercial breeders represented a significant risk factor for the development of a wide range of undesirable behavioral characteristics. Until the causes of the unfavorable differences detected in this group of dogs can be specifically identified and remedied, the authors cannot recommend that puppies be obtained from pet stores."

News: Karen B. London
Dogs Attend to Color
It matters more than brightness

One of the most persistent errors about dogs is the claim that they are colorblind. It has been known for decades that dogs can see colors, but research into the details of how they use their color vision can still reveal new information. In a recent study called “Colour cues proved to be more informative for dogs than brightness”, researchers asked the simple question, “Do dogs attend to color or brightness when learning the cues that indicate the presence of food?

In the experiment, researchers trained dogs to make a choice between boxes concealing food. The boxes were each marked with a colored paper, and the dog had to learn which one indicated a piece of meat was inside. Dogs were trained to discriminate between either light yellow and dark blue or between dark yellow and light blue. Then the dogs were tested to see if the cue they used to make correct choices was the color of the paper or the brightness of the paper.

For example, a dog who had learned to choose the box marked by a dark yellow piece of paper was tested with a choice between a box marked by light yellow or a box marked by dark blue. The experimenters were asking whether the dog had learned that “dark” indicates the presence of meat or whether “yellow” does. They found that dogs were making choices based on color, not brightness, in the majority of cases. It was a small sample size of only 8 dogs, but it suggests that dogs not only see color, which has long been known, but that they pay attention to it more than to the depth of color.

It is not surprising that if dogs have the ability to see color that they would use that color functionally in various situations. Asking whether dogs distinguish dark from light when the opportunity to distinguish by color is also present may be an important preliminary step in understanding what dogs attend to. However, I would be even more interested to know whether dogs favor color over shape, color over size or even color over various sounds to make their choices, as all of these seem more biologically relevant to dogs seeking food than brightness does.

News: Editors
Dogs are asked to "Do it"!
And imitate novel human actions and store them in memory

Researchers have shown that dogs can indeed not only mimic human actions, but can retain actions in their memory. According to a new study by Claudia Fugazza and Adám Miklósi, from Eötvös Loránd University in Hungary, this deferred imitation provides the first evidence of dogs' cognitive ability to both encode and recall actions. The research is published in Springer's journal Animal Cognition.

In order to test if dogs possess the cognitive ability of deferred imitation, Fugazza and Miklósi worked with eight pet dogs who had been trained in the “Do as I do method” by their guardians. While dogs are good at relying on human communication cues and learn by watching humans (and other dogs), what this study set out to test was if dogs can perform imitatively not directly after seeing a human do it, but some time after seeing the action.

So they made the dogs wait for short intervals before they were allowed to copy the observed human action. An example of the action done by the human and then performed by the dog was ringing a bell or walking around an object like a bucket.

“The researchers observed whether the dogs were able to imitate human actions after delays ranging from 40 seconds to 10 minutes, during which time the dogs were distracted by being encouraged to take part in other activities. The researchers were looking for evidence of the dogs' ability to encode and recall the demonstrated action after an interval.”

Fugazza described how one of the tests was carried out: “The owner, Valentina, made her dog, Adila, stay and pay attention to her, always in the same starting position. Three randomly chosen objects were set down, each at the same distance from Adila. When Adila was in position, Valentina demonstrated an object-related action, like ringing a bell with her hand.

“Then Valentina and Adila took a break and went behind a screen that was used to hide the objects, so that Adila could not keep her mind on the demonstration by looking at the object. During the break, Valentina and Adila either played with a ball or practiced a different training activity, for example, Valentina asked Adila to lie down. Or they both relaxed on the lawn and Adila was free to do whatever she wanted—sniff around, bark at people passing by, and so on.

“When the break was over, Valentina walked with her dog back to the original starting position and gave the command 'Do it!'. In a control condition, the ‘Do it!’ command was given by someone other than the owner, who did not know what action had previously been demonstrated by the owner. After the 'Do it!' command, Adila typically performed the action that was previously demonstrated.”

It is remarkable that the dogs were able to do this. But the length of time varied—with an action familiar to the dog, delays were as long as ten minutes. If the action/task was novel and the the dogs had not be exposed to it before, they were still able to perform it after a delay of one minute.

“The authors conclude: "The ability to encode and recall an action after a delay implies that the dogs have a mental representation of the human demonstration. In addition, the ability to imitate a novel action after a delay without previous practice suggests the presence of a specific type of long-term memory in dogs. This would be so-called ‘declarative memory,’ which refers to memories which can be consciously recalled, such as facts or knowledge."

To view more demonstration on the "Do as I do" method, see this, and the following demonstrations.

 

 

Reference

Fugazza C & Miklósi A (2013). Deferred imitation and declarative memory in domestic dogs. Animal Cognition; DOI 10.1007/s10071-013-0656-5

 

 

 

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