When a dog needs something from its human, it needs only to raise its eyebrows. Faced with those big “puppy dog eyes”, the human has little choice but to yield. This canine trait and the power it has in human-dog dynamics is, of course, no accident. According to a new study, dogs have evolved muscles around the eyes that allow them to be more expressive; muscles which wolves, dogs’ closest living relatives, lack.
Researchers at Howard University compared the facial anatomies of six domestic dogs and four gray wolves, along with behavioral changes in nine wolves and 27 shelter dogs. The researchers discovered that all the dogs had a muscle that pulls the lateral corner of the eyelid toward the ears when contracted. This very thin muscle, called the levator anguli oculi medialis, doesn’t exist in wolves, which can only mean that it appeared as a byproduct of canine domestication. It happened relatively fast too, over tens of thousands of years.
“We show that, in only 33,000 y, domestication transformed the facial muscle anatomy of dogs specifically for facial communication with humans. Based on dissections of dog and wolf heads, we show that the levator anguli oculi medialis, a muscle responsible for raising the inner eyebrow intensely, is uniformly present in dogs but not in wolves,” the authors wrote in the journal PNAS.
In order to study how dogs use their extra eye muscle, the researchers exposed the participating canines to humans for a couple of minutes. Compared to wolves, the dogs raised their inner eyebrows more frequently and with greater intensity than wolves.
Red highlights the anatomical differences in ocular musculature between the two species. Credit: PNAS.
The extra muscle allows dogs to be more expressive, and the researchers believe that it appeared as a result of human preference for traits that facilitate eye contact between dogs and humans. In time, dogs that were more emotionally expressive were selected by humans and bred more often than less expressive dogs.
“We know that humans favor dogs that show paedomorphic (infant-like) anatomical features like a large forehead, large eyes, and so on; in studies asking people to select pictures presenting dog (or cat) faces, people prefer the faces that present paedomorphic features over others,” the authors said.
Video: eye muscle intensity in wolves.
Video: eye muscle intensity in shelter dog.
Studies have shown that when a dog makes “puppy dog eyes”, humans are more likely to desire to look after them. Shelter dogs who widen their eyes and raise their eyebrows more often are also more likely to be adopted compared to dogs that are less expressive. In other words, we’ve manipulated dogs to the point that they evolved features to our liking. But, the tables have since turned. It is now dogs who manipulate us instead, with their irresistible adorable eyes.
For decades, scientists thought that dogs view the world in plain black and white. However, relatively recent research into canine anatomy and behavior shows that man’s best friend actually sees things in color, albeit not as well as humans.
The notion that dogs have poor vision and can only see in shades of gray can be attributed to Will Judy, the former publisher of Dog Week magazine in the 1930s.
“It’s likely that all the external world appears to them as varying highlights of black and gray,” Judy wrote in a highly popular 1937 manual called “Training the Dog.”
This myth surprisingly persisted for decades until research in the 1960s examining the structure of the canine eye shed more light on the matter.
The human eye perceives color when certain wavelengths of light are reflected off objects and into the lens. The refracted light is then focused on the retina where photoreceptors called cones and rods interpret the message in order to be processed by the visual cortex in the brain. There are millions of these photoreceptors throughout the human retina.
Rods are responsible for our ability to see in low light levels, or scotopic vision, allowing us to perceive shapes and motion even in dim light or almost no light at all. Cones are made up of three different types of receptors (short, medium, and long-wavelength cones) that allow us to perceive color.
The most important difference between the cone and the rod is that the cone is more light-sensitive than the rod and requires much more light to enter it in order to send signals to the brain. This explains why we can’t see colors in the dark.
Initially, it was thought that dogs lack cones, which led to the conclusion that they can’t see color. Anatomical dissections, however, showed that dogs also have cones, but much fewer compared to humans. Additionally, humans and other primates are trichromatic, meaning they have three kinds of cones, whereas dogs are dichromatic, only having two types of cones. Dogs are missing red-green cones, so they can’t see these colors.
On the upside, dogs have more rods than humans, allowing them to see much better in the dark than us. Dogs are essentially domesticated wolves, nocturnal predators that need to have good eyesight in the dark to track and catch prey. The canine eye also has a larger lens and corneal surface, as well as a reflective membrane behind the retina, called the tapetum lucidum, which further enhances night vision. The tapetum reflects back the light that has already entered the eye, giving the dog’s eyes a boost. This is the reason why your pet’s eyes may sometimes appear to glow at night.
Although dogs aren’t as good as humans in the vision department, they more than make up for it with their noses and ears. Canines’ hearing is keener than ours and their sense of smell is about 1,000 times more sensitive than the human nose.
How dogs see colors
All of this is to say that dogs aren’t fully color blind. In fact, in many ways, dogs probably perceive color similarly to humans with various forms of red-green color blindness. Certain colors aren’t vivid and different hues of the same color are difficult to differentiate between.
That’s because for the two types of cones dogs have, one is for blue while the other absorbs wavelengths between a human’s version of red and green.
But how exactly do dogs see color? That’s impossible to tell without swapping eyes with them, but judging from their anatomy it’s likely they see best in shades of yellow, blue, and green. When these colors are combined, a dog’s brain will likely process these wavelengths in dark and light yellow, grayish yellows and browns, and dark blue and light blue. This may explain why dogs go nuts over chasing yellow tennis balls. They probably can see the tennis ball light up, especially against a green grass background which, to them, comes across as rather dull.
The people at Dog Vision took this information about the canine eye and used image processing to offer a momentary glimpse into how dogs see the world. The blurry images below are not a perfect reflection of how a dog truly perceives shapes and colors, but they do a good job at illustrating how different their eyes are from ours.
The reason why these images are blurry is that dogs tend to be nearsighted. A poodle, for example, is estimated to have 20/75 vision. However, dogs are much more sensitive to motion at a distance — anywhere from 10 to 20 times more sensitive than humans.
Owing to thousands of years of selective breeding, humans and dogs have co-evolved a special link. This is best seen in the interspecies communication between the two. Dogs can understand and follow human gestures, something that even the brainy chimps, our closest relatives, cannot do. In turn, humans can tell if their dogs are in need of food, water, a walk, or a gentle pet despite the lack of verbal communication.
Although dogs communicate with humans through a repertoire of vocalizations such as barks, growls, howls, whines and whimpers, screams, pants, and sighs, their primary mode of communication is by body language. These non-verbal cues include ear and eye position, body position and movement, facial expressions, and, last but not least, tail carriage and motion.
Why do dogs wag their tails: the unspoken language of canines
Concerning tail wagging, most people associate this motion with the dog being ‘happy’. While there is some truth to this notion, it is not entirely accurate and does not describe a dog’s true emotional state in all instances of tail motion. That being said, a dog’s tail position is instinctual and thus a pretty good gauge of your canine’s internal state — it’s just that they do it when they’re not happy as well.
Tail wagging develops between three and four weeks of age depending on the breed. When a dog is relaxed, the tail will rest in its natural position. However, this position can differ from breed to breed. For the vast majority of dogs, their relaxed tails hang down to their heels. However, a pug’s tail curls upward and, on the opposite end of the wagging spectrum, greyhounds have tails that rest slightly between their legs. You can use this tail position as a sort of reference from which you may attempt to infer your dog’s emotional communication.
According to the American Society for the Prevention of Cruelty to Animals, when a dog is anxious or overly submissive, it will hold its tail lower than its natural position. When scared or outright terrified, the tail will hang under its body. A slightly higher than usual tail position may indicate arousal and curiosity, while a vertical tail may reflect aggression.
Tail wagging typically indicates excitement. The more vigorous the wagging, the greater the excitement. In fact, the speed of the wag, depending on the tail’s position, is typically an indicator of enhanced emotional state, whether it’s positive or negative.
Dog’s internal state
No wag, tail hanging down near heels
This neutral position indicates relaxation.
Tail between legs or tucked
Big tail wag + body wiggle
Dog is extremely happy and ready to interact with human
Slightly up in the air
Vertical tail high in the air
Can indicate dominance and aggression. Best to give the dog space
Tail wagging to the right
Positive feelings like excitement or interest
Tail wagging to the left
Negative feelings like anxiety or aggression
This can mean that the dog is happy to see its owner or to be offered a treat. However, just like humans, dogs can get excited about all sorts of things — and they’re not always necessarily positive.
A 2013 study by researchers at the University of Trento in Italy found that dog tail wagging conveys a wealth of information to other dogs, particularly in the direction of the tail. Canines that see tails wagging to the right are more relaxed, whereas they become more stressed when they see tails wagging to the left. Previously, the same team of Italian researchers found that dogs wag their tails to the right when they see something they’d like to approach. When confronted with something they want to stay away from, such as another dog that exhibits an aggressive posture, canines will wag their tails to the left.
This directional tail wagging is mediated by the activation of the left or right side of the dog’s brain. Subsequent observations showed that dogs that saw other canines wagging their tails to the left had a higher heart rate and showed more signs of stress and anxiety. When they saw other dogs’ tails wagging to the right, they were more relaxed.
The direction refers to the dog’s left or right viewed from the rear as if you are facing in the direction the dog is viewing. That means that if you are facing the dog and drew an imaginary line down the middle of his back that positive, right-sided signal would appear as tail swings mostly curving to your left. Dogs will of course wag their tails in both directions, but pay close attention to which direction the tail is more biased towards.
The researchers don’t think that the dogs are consciously responding to the direction of tail wagging. Dogs may become more stressed when seeing a left tail wag because they’re interpreting that the canine they’re facing might be more likely to attack.
Previous research focusing on the approach-avoidance behavior of other animals found that the left hemisphere is associated with the processing of positive-approach emotions while the right hemisphere is associated with negative-avoidance emotions. The brain’s left hemisphere controls the right side of the body, and vice-versa, dogs have learned to read these unintentional cues in body language.
Canine tails beyond communication
Besides assisting in communication, a dog’s tail has a wide range of functions. When they’re swimming, the tail can act as a rudder in the water while outside it helps the dog keep balance when running, allowing them to make tighter turns without falling over.
Until not too long ago, many dog owners would dock the tails and crop the ears of their pets for cosmetic reasons. If a dog has a docked tail it’s often difficult to tell how they’re feeling.
Both practices are severely detrimental to a dog’s health and ability to communicate properly. In many places in Europe, such as the UK and Germany, these practices have been banned. Unfortunately, there are no such restrictions in the United States, although New York and Vermont have considered bills to make the docking and cropping illegal.
Bottom line: wagging doesn’t always indicate the dog is happy. Pay attention to the speed and direction of the wagging tail to get a better idea of what your dog is trying to communicate.
Dogs can understand and respond to human communication from a very early age and with virtually no training, unlike other domesticated species. You might not think much of it when you play fetch with your dog, but this simple act of communication and coordination is a pretty big deal from both a cognitive and evolutionary standpoint. This suggests that the strong bond between humans and dogs has led to co-evolved traits that have turned dogs increasingly social towards us. In a new study, researchers at Duke University argued in favor of this notion, after showing that wolf pups could not understand human gestures meant to help them find tasty treats, whereas dog puppies aced the test despite having no training.
“It was important to us to test puppies, not just adult dogs and wolves, because we wanted to see whether there is an innate species difference, which cannot be explained solely by learning over life experience,” Hannah Salomons, a doctoral student at Duke University, told ZME Science.
“The main finding of this study is that compared to wolf puppies, dog puppies have high levels of social skills that allow for cooperative communication, such as understanding that a human gesture is meant to help them find hidden food. The dog puppies were also far more attracted to humans, and would approach both strangers and familiar people more often than the wolf puppies. However, on non-social tasks, the dog and wolf puppies performed similarly,” she added.
The gestures of domestication
Dogs and wolves share close ancestors and researchers have been studying their similarities and differences for years, hoping to deconstruct the origins of canine domestication. Previously, scientists had compared dog and wolf social abilities, showing that dogs seem to have an innate ability to respond to human-given cues such as pointing gestures whereas wolves need special training.
The new research at Duke University is similar in scope to other studies, but with a much higher sample size of cute puppies and adorable pups. While other studies used at most 12 puppies of each species, this time the researchers worked with three dozen puppies per species, which offers much better confidence in the statistical significance of the findings. The wolf young were also genetically tested in order to confirm that the puppies were indeed wolves and not some dog hybrid, something no previous such study verified before.
The 37 wolf puppies were raised at the Wildlife Science Center in Minnesota where they were surrounded and cared for by humans almost round the clock. But despite the ubiquity of human interaction, the wolf pups were still very shy and would only come out of hiding when in the presence of caretakers they knew well. In contrast, the 44 puppies from Canine Companions for Independence spent most of their time in the company of their mothers and littermates and had minimal human contact when they were enrolled in this study.
“Being able to test such a large sample of wolf puppies was a huge undertaking, that took our team over six years to complete – only a few litters are born at Wildlife Science Center per season, and despite being raised by humans round-the-clock from just a few days old (which, I should note, is part of WSC’s typical husbandry practice, not done for the purpose of this study, and is a huge feat in and of itself), some of the wolf puppies are so shy around people that they never warm up to the experimenter enough to participate in the study. I have some great memories of sitting in the wolf pup enclosure for hours at a time, seeing them go from hiding when I first entered to frolicking and playing as they acclimated to my presence, and being rewarded with one pup dragging over a nice ripe piece of deer carcass (her favorite food) to sit next to me and gnaw on!” Salomons said.
In order to assess their communication skills, the young canids were pitted against each other in a series of tests. During one such task, the dog and wolf puppies had to find a treat hidden beneath one of two bowls. To help them out, the researchers pointed and gazed towards the correct location of the stashed food. In other tasks, a human planted a small wooden block beside the right spot to indicate where the food was hidden, a gesture that neither of the two types of pups had seen before.
The results spoke for themselves. Despite their lack of formal training, 17 out of 31 dog puppies consistently went to the right bowl, whereas none of the human-reared wolf pups performed better than a coin toss. Subsequent trials showed that the puppies were guided by human gestures rather than the odor of food.
Many of the puppies completed their trials on their first go, which suggests that this remarkable ability is hard-wired in the dogs’ brains. But that’s not to say that dogs are smarter than wolves. Chimps, our closest relatives along with bonobos, can’t read human gestures, although they’re much better than dogs at complex cognitive tasks.
All pups are good boys and girls
Evolution does not produce species that are ‘better’ or ‘worse’ than others but rather fosters species that are most adapted to their environment. Both canids have more or less the same cognitive abilities in terms of memory and motor impulse control. It’s just that puppies have much better people skills due to their close proximity to our species for thousands of years.
Emily Bray of the University of Arizona and colleagues showed in a 2021 study that puppies as young as eight weeks can understand instructions from humans, such as finger-pointing and gazing towards an object. This study found that 40% of the variation in a puppy’s ability to follow a human’s finger-pointing or gaze can be explained genetically, which makes sense in light of other findings. We know from previous research that breeds of dogs that were initially selected for cooperative work (like sheepdogs) are much better at following a person’s point than breeds selected for other kinds of work like guard dogs, hounds, or sled dogs).
This familiarity and strong bond with humans is perhaps best evidenced by how wolf and dog puppies differ in the way they respond to strangers. Tests showed that dog puppies were 30 times more likely to approach a stranger than the shy wolf pups.
Previously, researchers in Austria and Hungary also assessed wolf and dog pups’ ability to follow human gestures. They found that dogs as young as four months of age understand pointing gestures to find hidden food even without intensive early socialization. Wolf pups, on the contrary, do not attend to this subtle pointing. Interestingly, this particular study found that wolves socialized at a comparable level to dogs are able to use simple human-given cues spontaneously if the human’s hand is close to the baited container (e.g. touching, proximal pointing). The wolves also responded to gestures pointing to objects at a distance if they received formal training. This isn’t that surprising considering how closely related the two species are, but the effects of domestication on people’s skills are quite striking.
“The evidence from this study along with many others makes it very clear that dog puppies can understand humans’ cooperative communicative gestures from a young age, without any explicit training or intensive human experience,” Salomons said.
“As for why other domesticated animals may not show the human-like cooperative communicative ability seen in dogs, this is likely to be constrained by the pre-existing social cognitive abilities of their wild predecessors. As wolves already had fairly complex social skills, as the domestication process progressed and an attraction to humans replaced fear, they were able to apply these skills in new ways and they began to emerge earlier in development. Other species, such as the wild predecessors of sheep or cattle, may not have had similar starting levels of social skills for the domestication process to shape. Even so, evidence is coming out that in other species, such as ferrets, domesticated populations do outperform wild populations at reading human gestures!”
According to Salomons, these findings show that domestication, by selecting for attraction to humans, altered dogs’ social development, resulting in the remarkable cooperative-communicative abilities we see today. Scientists aren’t exactly sure how all this happened, but perhaps it all started with a few wolves that were unusually friendly towards humans and that received food scraps in return for their non-aggressive behavior. Over time, wolves that were friendly towards humans had a better chance of reproducing and passing on their ‘tamed’ genes whereas wolves that were fearful and aggressive towards humans stayed to themselves. After hundreds of generations, this common ancestor speciated into Canis familiaris, the faithful canine we all love and cherish.
“This knowledge is important because understanding how dogs’ minds are wired can help us learn to communicate with them better and work together as a stronger team. Also, a similar process, known as self-domestication, may have occurred over the course of human evolution as well, so understanding its effects may shed light on the development of our own minds,” Salomonds concluded.
In the future, the researchers plan to perform a longitudinal study that charts the temperament and performance of individual puppies on social and non-social cognitive tasks to see how these different cognitive aspects develop and change over time and how they interact with one another.
Researchers have been studying dogs for decades or even centuries, but we’re constantly learning new things about them.
Dogs really are man’s best friend — and also our oldest friend
A 2020 DNA study found that dog domestication took place some 11,000 years ago, towards the end of the last Ice Age, indicating that our relationship with our furry friends goes back a long way.
A team of geneticists from 10 countries joined forces with archaeologists to sequence the genome of 27 ancient dogs, obtained from Europe, Siberia, and the Middle East. They found that, although the history of humans isn’t always perfectly intertwined with that of dogs, they were indeed the first domesticated animal, probably from wolves, and they’ve been by our side since the dawn of civilization.
Dogs also dream, but we’re not exactly sure what
A series of studies from the past two decades have shed new light on dog dreams, and as far as researchers can understand, not only do dogs dream, but they have complex dreams that help them be healthier and happier. A 2016 study found that dogs who sleep more are happier, while another recent, 2020 study found that sleep sleep may contribute to dogs’ memory consolidation.
Unfortunately, dogs also seem to have nightmares sometimes. But there’s some good news: the best way to ensure that a dog has happy dreams is to keep them happy during daytime — and happy dogs are truly what the world needs more of right now.
Both a wet nose or a dry nose can be normal
The old adage says that a wet nose is a healthy dog, but researchers from Eötvös Loránd University in Budapest, Hungary, have shown that that’s not necessarily the case: both wet and dry noses can be normal. For example, dogs’ noses are typically warm and dry when they sleep.
Researchers have previously speculated that dogs lick their nose and keep it wet either for heat regulation or to aid their keen sense of smell. In the new study, however, authors suggest that dogs and other cold-nosed animals employ heat detection in their hunting routines, in addition to their already keen sense of smell.
Chocolate really is poisonous for dogs
Unlike cats, which lack the ability to taste sweetness, dogs find chocolate just as appealing as humans. Well, as some humans, at least. But while the dark treat can be a euphoric delight for us, it can be poisonous to canines. The main problem is the chemical compound theobromine, found in dark chocolate and cocoa. Dogs can’t break down or metabolize theobromine, which means that it can act like poison for our furry companions.
Not all dogs get poisoned by chocolate and the dose makes the poison. Mild symptoms of chocolate toxicity occur when a canine consumes 20 mg of theobromine per kilogram of body weight. Cardiac symptoms occur at around 40 to 50 mg/kg and dangerous seizures occur at doses greater than 60 mg/kg. Raisins and grapes are also very toxic to some dogs, though researchers are not sure exactly why. Dogs should never be fed grapes or chocolate.
Cats and dogs don’t always fight like cats and dogs — and pheromones can help where they do
In the UK, 7% of households own both cats and dogs… and yet they live in peace and harmony most of the time. Many cats and dog owners report that their animals are comfortable in each other’s company, but this isn’t always the case. Conflicts between pets are one of the most common reasons why animals are returned to shelters, and a team of researchers wanted to see how these conflicts could be addressed.
A team of researchers in the UK found that soothing pheromones can not only decrease the number of aggressive interactions between cats and dogs, but can even increase the number of friendly interactions. Dog pheromones in particular led to the greatest increase in friendly interactions.
3 out of 4 dogs suffer from some form of anxiety
The life of a doggo isn’t always easy — even when you are the best boy or girl. A surprisingly high percentage of dogs actually suffer from anxiety of some sort, which can manifest through symptoms such as excessive barking, destructiveness, aggression, or fearfulness. The fact that so many dogs have anxiety came as a surprise to many dog owners, researchers noted.
The best thing to do to prevent and tackle anxiety in dogs is to keep them happy. This starts with picking the right breed (don’t pick a very active breed unless you can really dedicate time and effort to it), making sure that the dog has enough exercise, and give your dog attention. Most dogs hate spending time alone, and can get stressed out. Dogs also tend to mirror their owners’ stress levels — so keeping yourself happy also helps.
The ridiculous voice we use to talk to dogs? They love it
You know that high-pitched, exaggerated voice that some people use to talk to a dog? The emotional “who’s a good boyyyy”? Surprisingly enough dogs, actually like it. Just like how baby-talk can help adults bond with babies, “doggy-talk” can help humans bond with dogs, a recent study has shown.
Dogs were much more likely to want to interact and spend time with those who used dog-directed speech compared to the control group. Researchers only tested adult dogs, and they noted that it is maybe the combination of the acoustic properties and the dog-related content that dogs enjoy. So if you do the “doggy-talk”, make sure to mention walks, treats, dog, and of course, ‘good’.
Dogs can navigate using the Earth’s magnetic field
Stories of dogs who traveled immense distances to find their way back home are surprisingly common… so how do they do it? Their keen sense of smell can sure help sometimes, but that doesn’t work as well for very large distances. In a recent study, researchers have shown that dogs have an internal compass which they can use to orient themselves based on the Earth’s magnetic field.
This was previously suggested by researchers who found that dogs can sense the Earth’s magnetic field… while pooping. Dogs seem to prefer to poop in the north-south axis, and recent experiments confirmed that this doesn’t only happen when pooping, it actually happens a lot, and it helps dogs find their way with remarkable accuracy.
Dogs know they’re doing “puppy eyes” — and they use it to manipulate you
A 2020 study found that the infamous puppy dog eyes expression isn’t just a way for dogs to express sadness — sometimes, they use it as a clever ploy to receive attention and affection. Although the study was carried out on a small sample size, researchers are pretty confident that at least sometimes, dogs know what they are doing.
It’s possible that dogs picked up this communication trick as they were domesticated, researchers believe. It could also be a way for dogs to mimic humans, in an attempt to make us feel more empathetic to dogs, and maybe giving them what they want. The second theory is that it’s a way to make themselves cuter, and again, maybe just getting that extra treat.
Dogs (and wolves) have a sense of fairness
Although dogs can be a bit sneaky sometimes, they also have an innate sense of fairness. As many dog owners can attest, dogs recognize when they are treated fairly or unfairly, and this appears to predate domestication — indicating that it’s not something they acquired during their cohabitation with humans.
A research from 2017 found that both dogs and wolves share the same reaction, and more dominant individuals have an even stronger sense of fairness. “These results suggest that the inequity response found in pack-living dogs and wolves is comparable to that observed in non-human primates,” the study notes.
Dogs can make you seem more attractive
A surprising statistic notes that 22% of men (but only 6% of women) with pets used their pet to attract potential dates. The even more surprising thing is that it kind of works. Dogs seem to be the ‘sexiest pets’ out there, and they can help men get dates both in real life, and online.
Several studies have suggested that dogs really do make men seem more attractive. In 2008, two French social psychologists had one young man named Antoine approach 240 randomly selected women and he was 3 times more successful when he was accompanied by a dog than when he was alone. But please, please, don’t get a dog just to help with dates — a dog is a serious commitment that deserves a lot of attention and care.
Dogs can tell when you’re happy or upset
While this has been suggested several times in the past (mostly anecdotally, by dog owners), the first tangible evidence came in 2015. A study had dogs look at images representing human emotions and were remarkably capable of telling when humans (not just their human) was happy or sad.
“Our study demonstrates that dogs can distinguish angry and happy expressions in humans, they can tell that these two expressions have different meanings, and they can do this not only for people they know well, but even for faces they have never seen before,” said one study author.
Dogs can accurately diagnose a number of diseases, including COVID-19 and some types of cancer
For years, researchers have suspected that dogs’ sniffing abilities could be used for something more than tracking drugs and explosives, but in the past few years, we’ve seen a surge in this type of research. As it turns out, when you train dogs (specifically breeds with the most sensitive noses), they become capable of detecting diseases.
The mental state of our pets is a subject of heated scientific debate. Understandably, dogs or cats can’t really explain what’s going on, but researchers have done their best to figure out whether dogs can experience things like anxiety and depression. The verdict is still not 100% out, but the strength of evidence seems to suggest that the answer is ‘yes’, dogs can get depressed, they’re sometimes prescribed even special antidepressants.
Research into dog psychology is still ongoing Remember, dogs sometimes mirror the stress and emotional states of their owners — so one of the things you can do to improve your dogs’ mental health is to take care of your own mental health. Luckily enough, dogs have also been shown to help with that.
Breed is not the main determinant of aggression
Although acts of dog aggression towards humans remain rare, some breeds have an undeserved bad reputation. For instance, a 2008 study found that some of the most aggressive breeds towards humans are Chihuahuas and Jack Russell Terriers, but the aggressiveness differs towards humans they know, humans they don’t know, and other dogs.
Overall though, studies are increasingly showing that when it comes to aggressiveness, breed is not a major determinant. Instead, researchers suggest, we should focus on other factors that influence the risk of aggression. A dog that is loved and cared for has a much lower risk of being aggressive than one who is neglected or even worse.
Owning a dog will make you healthier
Okay, I cheated a bit here. All the entries on this list are new facts we’ve only learned about dogs recently. This has been discussed for decades and is essentially a well-known fact at this point. But I do have one reason for introducing this here: modern science has confirmed it.
The key difference here is physical activity. While walking is often regarded as an easy and accessible way to be active, it still counts, and it’s still useful. Dog owners are, on average, more active, which means they’re healthier. But once again, this is a reminder that owning a dog is an every-day responsibility: you can’t skip out on walks just because you don’t feel like it!
So there you have it, just some of the dog facts we’ve learned recently, thanks to modern science. Although we’ve been together for thousands of years, our relationship with dogs remains as complex and charming as ever.
Undoubtedly, more studies will reveal even more facts about our beloved companions. Did we miss anything that should be here? Be sure to share it in the comment section.
Most dog owners will tell you that their pets are awesome. They love their dogs, and their dogs seem to love them back. But do dogs genuinely feel love or any kind of positive emotion similar to how a human does for that matter? This is a question that has eluded scientists for a long time.
It’s easy to put a dog’s tremendous enthusiasm whenever their owner comes home as just as a form of attachment, viewing the human as a walking, breathing food dispenser and nothing more.
But a breakthrough research might change the way people view dogs forever. According to neuroscientist Gregory Berns, “dogs are people, too.”
He reached this conclusion after performing MRI scans on over a dozen dogs, finding the same brain region responsible for positive emotions in humans is activated in dogs as well.
To infer animal sentience and other neurological traits, scientists rely on animal behaviorism. You can’t ask a dog how it feels, or what it’s thinking. As such, it’s been considered an extremely challenging area of research. By using brain scans, however, one can bypass having to directly ‘speak’ to an animal. Instead, you let the brain do all the talking.
But this doesn’t mean performing MRI on animals is straightforward. The machines are racketing, claustrophobic, and generally unpleasant even for humans. For them to work you have to stay completely still. You can imagine how difficult it is to get a hyper labrador to stay put while all kinds of machinery are diverting its attention. Typically, veterinarians perform anesthesia on dogs whose brain scans they need to perform, but this renders any kind of emotion monitoring useless.
Dog emotions, not too different from ours
Berns tackled this issue by training dogs using painstaking reward exercises to stay still when inside the operating MRI, and in doing so he has performed the first wake dog MRIs, as reported in PLOS ONE. Inside the scanner, the dogs’ brain activity was measured for a two-hand signal (which they learned to associate with food), as well as for scents of familiar and unfamiliar dogs and humans.
Both the human and dog brains are strikingly similar in function and structure in one key region: the caudate nucleus. Located between the brainstem and the cortex, the dopamine-rich caudate plays a key role in the anticipation of things we enjoy, like food, love, and money — things that are associated with positive emotions.
“Many of the same things that activate the human caudate [part of the brain], which are associated with positive emotions, also activate the dog caudate. Neuroscientists call this a functional homology, and it may be an indication of canine emotions,” Berns wrote in an article for the NY Times.
Berns with one of the dogs from his research. Credit: Gregory Berns.
In response to hand signals indicating food, as well as smells of familiar humans, the canine caudate activity increased. And in preliminary tests, it activated to the return of an owner who had momentarily stepped out of view. Neuroscientists call this a functional homology, and it may be an indication of canine emotions.
“The ability to experience positive emotions, like love and attachment, would mean that dogs have a level of sentience comparable to that of a human child. And this ability suggests a rethinking of how we treat dogs,” Berns said.
“DOGS have long been considered property. Though the Animal Welfare Act of 1966 and state laws raised the bar for the treatment of animals, they solidified the view that animals are things — objects that can be disposed of as long as reasonable care is taken to minimize their suffering.”
“But now, by using the M.R.I. to push away the limitations of behaviorism, we can no longer hide from the evidence. Dogs, and probably many other animals (especially our closest primate relatives), seem to have emotions just like us. And this means we must reconsider their treatment as property.”
So, do dogs truly love us? We can’t be sure, but next time you see your dog wag his tail you can be sure he’s happy, scientific proof included.
Several studies have suggested that with training, dogs could be used to sniff out infections. Now, it’s finally being put to practice — and it only takes seconds.
Land in Helsinki, Finland, and you’ll be asked to dab your skin with a napkin. As you wait for a few minutes, the napkin will be sent to a separate booth where it will be tested. Except this testing equipment isn’t what you’d imagine — it has 4 paws and it’s fluffy.
After being presented with the napkin and other control scents, the dog starts sniffing and indicates when it has detected the virus (either by pawing, yelping, or just lying down). If this happens, the passenger will then be asked to take a free PCR test using a nasal swab.
However, the dog test might be even more accurate than the PCR itself. Dogs are able to identify COVID-19 from only 100 molecules, whereas the test equipment needs 18,000,000, says Helsinki airport. According to the researchers who oversaw the dogs’ training, the success rate is close to 100%, and they can identify the virus several days before any symptom has manifested.
It’s not the first time dogs have been suggested as a detection mechanism for COVID-19, and, in fact, our canine friends have shown remarkable prowess at detecting a range of diseases, from cancer to diabetes.
“As far as we know no other airport has attempted to use canine scent detection on such a large scale against COVID-19. We are pleased with the city of Vantaa’s initiative. This might be an additional step forward on the way to beating COVID-19,” says Airport Director Ulla Lettijeff from Finavia. Vantaa is the small city at the edge of Helsinki where the airport lies.
The dogs have been trained at Wise Nose, a Finnish organization specialized in training animals for scent detection. As far as we could find, there is no published peer-reviewed study of the Finnish dogs, but according to statements from officials, the results have been robust enough to deploy the dogs. Based on what is publicly available, the dogs’ results are comparable or superior to existing PCR tests.
At the moment, Wise Nose is training 16 dogs for the project, with four of them — ET, Kossi, Miina, and Valo — already working in shifts of two. The whole project is set to last 4 months (in the first stage) and cost €300,000 ($349,000 USD), substantially cheaper than other tests.
In the future, dogs may play an even bigger role in COVID-19 detection, but proper legislation must first be passed to allow this.
A similar but smaller trial has begun at the Dubai airport. Australia, France, Germany, and Britain are working on similar projects.
Dog navigation has been a black box for researchers. The way they find their way from place to place, often across great distances, has been a hard to crack mystery. Their keen sense of smell can sure help sometimes, but smell alone doesn’t explain how dogs can navigate over great distances.
In a new study, researchers describe one potential mechanism that helps dogs find their way: their internal compass.
The idea that dogs orient themselves using the Earth’s magnetic field is not new. Curiously, previous studies have shown that dogs tend to align themselves on the north-south axis when they poop or urinate. As funny as this sounds, it’s indicative of an intriguing underlying mechanism: somehow, dogs sense the Earth’s magnetic field, and align themselves to it under certain conditions.
So the next question is — can they use this for navigation?
To analyze this, PhD student Kateřina Benediktová from the Czech University of Life Sciences Prague carried out two experiments using 4 and 27 dogs, respectively, to see how they find their way.
Both experiments had the same format: Benediktova and colleagues attached GPS sensors to dogs, took them out to a natural environment, and let them run about. In all cases, dogs went and did their thing and then returned to their owner.
However, when researchers analyzed the path dogs took to return, a few interesting patterns emerged.
First of all, some of the dogs went and returned on the same path. This is where their exceptional sense of smell comes into play as it helps them find their way back. This type of behavior was called tracking, because dogs tracked their own path.
But in the second type of behavior, dogs left on one path and returned on another. This behavior is called scouting, because they scout a different path. Sometimes, the dogs used a combination of both.
It gets even more interesting: most of the scouting dogs also engaged in an odd behavior: they would sometimes run 20 meters on the north-south line, before returning to their starting point. The study authors believe this helped them find their bearings, much like a person would align the compass on north-south for easier orientation — and dogs that did it were more efficient in their return. In 170 of the 223 documented dog trips, dogs practiced this behavior.
It’s always hard to demonstrate whether animals are orienting themselves using magnetism alone. To be 100% sure of this, you’d basically have to make sure the animal isn’t using any of its other senses, which is not easy to do. However, the fact that such a similar behavior was observed in so many different dogs seems to be strong evidence, and it’s the closest you can get to a smoking gun. No other factors (such as wind, location, or the dog’s gender) seemed to make a difference in improving navigational efficiency, further supporting the idea that the dogs were able to use the Earth’s magnetic field to navigate.
If this is the case, it would probably indicate an old navigation method, from when dogs were still a wild species.
Many biologists believe that not just dogs, but all animals that range over long distances can orient themselves using the Earth’s magnetic field. It’s even suspected that humans can do it, but we’re not nearly as good at it as other species.
Honey bees have the ability to detect the Earth’s magnetic field using iron granules in their abdomen. Frogs, snails, and even some bacteria can do it, and this is still actively researched in a number of mammals, including mice and foxes. It’s pretty neat to see that dogs can do it too.
New research at the University of Copenhagen (UoC) finds that sled dogs are a much older lineage than previously believed. Their ancestors, the team reports, worked and lived with humans in the Arctic for almost 10 millennia.
Man’s best friend is almost ubiquitous in society today as pets, service, and working animals. We know their origin story in large strokes — dogs evolved from domesticated wolves — but the exact details of this process are still unclear.
The team at the UoC’s Faculty of Health and Medical Sciences, in collaboration with researchers from Greenland and Barcelona, analyzed the genomes of ancient and modern sledge dog species to better determine their history. Such dogs evolved much earlier than assumed, they explain.
“We have extracted DNA from a 9,500-year-old dog from the Siberian island of Zhokhov, which the dog is named after,” says co-lead author Mikkel Sinding, a Ph.D. student at the Globe Institute in Barcelona.
“Based on that DNA we have sequenced the oldest complete dog genome to date, and the results show an extremely early diversification of dogs into types of sled dogs.”
Modern breeds such as the Siberian Husky, the Alaskan Malamute, and the Greenland sled dog share an important amount of genes with the Zhokhov dog. This suggests the sled dog lineage is at least as old as it and remained quite isolated from other populations of wolves and dogs for the most part.
As part of their study, the team also sequenced the genomes of a 33,000-year-old Siberian wolf and ten modern Greenlandic sled dogs. These were there compared to genetic data from modern dogs and wolves across the globe.
“We can see that the modern sledge dogs have most of their genomes in common with Zhokhov. So, they are more closely related to this ancient dog than to other dogs and wolves,” says Sinding.
“But not just that — we can see traces of crossbreeding with wolves such as the 33,000-year-old Siberian wolf — but not with modern wolves. It further emphasises that the origin of the modern sledge dog goes back much further than we had thought.”
Historical population data also shows that Greenland sled dogs were stable in numbers up to around 850 years ago when they went through a “bottleneck”. This coincides with the Inuits colonizing Greenland, the authors explain. This points to the lineage being isolated in the area before and after humans entered their ecosystem.
While modern sledge dogs share more of the genetic makeup of the Zhokhov dog than other modern breeds, we still don’t know when this split in lineages took place, or why. However, Greenland sledge dogs are the most genetically-remote from other modern dog species.
Some of the genetic differences between these two groups include genetic adaptations for a starch- and sugar-rich diet that the sledge dogs lack. Instead, their genetics favor diets with a lot of fat, similar to that of Arctic natives or polar bears.
“This emphasises that sledge dogs and Arctic people have worked and adapted together for more than 9,500 years. We can also see that they have adaptations that are probably linked to improved oxygen uptake, which makes sense in relation to sledding and give the sledding tradition ancient roots,” concludes Associate Professor Shyam Gopalakrishnan, the other co-lead author.
The paper “Arctic-adapted dogs emerged at the Pleistocene–Holocene transition” has been published in the journal Science.
Many mammals, including canines, have whiskers. Some dog owners think these whiskers are just longer unruly hairs that can be groomed and even snipped off entirely — but this would be a huge mistake. The whiskers, technically known as “vibrissae”, serve important specialized functions that help dogs sense the world around them and coordinate their movement.
Humans sense touch through millions of sensory receptors that line the skin and deeper tissue. Unlike humans, the follicles of the coarse hairs protruding from a dog’s muzzle, jaw and above its eyes are also packed with nerves that relay sensory information.
Essentially, these whiskers allow dogs to sense objects and the world around them as humans do with fingers.
What are a canine’s whiskers good for
The tactile sensation is made possible thanks to Merkel cells, which are specialized skin receptors associated with nerve terminals. A dog’s mouth and snout are very rich in Merkel cells, according to a study published in the journal Veterinary Science.
According to researchers, these tactile hairs serve a variety of functions. For instance, the whiskers allow dogs to gather information from subtle changes in air currents about size, shape, and speed of nearby objects. Ultimately, this allows canines to see their surroundings better, even in dark. It’s well known that vision isn’t a dog’s strong point, so their vibrissae greatly assist them — especially when dealing with close objects (dogs are farsighted). Whiskers beneath the chin allow dogs to “see” objects obstructed by their snouts.
Whisker’s positioned immediately above the eyes are particularly important for vision. When an object or strong airflow causes these whiskers to flex, dogs will reflexively blink in order to protect their eyes.
It’s not clear whether dogs use their whiskers for food acquisition. However, if they’re anything like rats, seals, and walruses — all related species that have been shown to use their whiskers to find food — dogs might very well use their sensing hairs for this purpose, too.
A dog’s whiskers can also serve an important role in communication with other canines or other species. Like many other mammals, when a dog is threatened it will automatically flare its whiskers, pointing them in a forward direction. This signals to predators and other aggressive animals that the dog is ready to defend itself and respond with violence.
Dogs may use their whiskers to also disperse pheromones, keep their head upright when swimming, and monitor their environment.
About 40% of a canine’s visual cortex (the part of the brain responsible for processing vision) is devoted to mapping information from whiskers. They’re that important!
What you need to know about your dog’s whiskers
Although they might look similar, vibrissae are distinct from body hair. The main difference is that a dog’s whiskers are directed by the nervous system and contain nerves.
Unlike cats, which have four rows of whiskers on either side of a cat’s face, the placement of a dog’s whiskers is less predictable. Some have a multitude of vibrissae, others may have few or even none. You should find them above the eyes, on both sides of the muzzle, above the upper lip (pointing down) and beneath the dog’s chin.
According to scientists, there are no breed-specific differences in canine whiskers. An exception may involve hairless breeds, which have no whiskers at all.
That being said, you should never trim your dog’s whiskers. Some pet owners believe their dogs’ whiskers should be groomed and snip them for aesthetic purposes.
This practice won’t hurt the dog, because there are no pain receptors found in whiskers. However, given the multitude of functions they serve, a whisker-less dog will become confused, disorientated, and less able to navigate its spatial surroundings. If you cut your dog’s whiskers in the past out of ignorance, know at least that they will grow back naturally.
In summary, dogs use their whiskers as a sort of radar to detect objects that they cannot properly see with their own eyes.
Two recently published studies have associated dog ownership with reduced all-cause mortality. The protective effect of canine ownership is especially pronounced in the case of cardiovascular disease. The researchers found that, compared to non-owners, dog owners experienced a 24% reduced risk of all-cause mortality and a 65% reduced risk of mortality after suffering a heart attack.
In the past, studies have shown that having a dog alleviates the symptoms of social isolation. Solitary people typically don’t exercise, but having a dog forces people to go outside and have a walk at least once per day. Having a canine around also seems to lower blood pressure, which might explain the better cardiovascular outcomes.
In the first study, researchers compared the health outcomes of dog owners and non-owners after a heart attack or stroke using data from the Swedish National Patient Register. The participants involved in the study were aged 40 to 85 and experienced a heart attack or ischemic stroke between 2001 and 2012.
The studies found that the participants who owned a dog had a 33% lower risk of death from a heart attack if they lived alone and 15% lower if they lived with a partner or child. The risk of death for stroke patients living alone was 27% and 12% for those living with other people in the household, as reported in the journal Circulation: Cardiovascular Quality and Outcomes.
The Swedish researchers claim that the lower risk of death can be explained by increased physical activity and lower levels of depression and loneliness.
“We know that social isolation is a strong risk factor for worse health outcomes and premature death. Previous studies have indicated that dog owners experience less social isolation and have more interaction with other people,” said Tove Fall, D. V. M., professor at Uppsala University in Sweden. “Furthermore, keeping a dog is a good motivation for physical activity, which is an important factor in rehabilitation and mental health.”
In the future, the researchers would like to explore this link even further in order to tease out the causal relationships. It might be possible, for instance, that doctors might someday prescribe ownership of a dog to certain vulnerable patients, based on a new evidence-based policy.
A second study, this time a meta-analysis (a study of studies), involved 3.8 million people pooled from 10 separate studies. Compared to non-owners, people with dogs had a 24% reduced risk of all-cause mortality, a 65% reduced risk of dying from a heart attack, a 31% reduced risk of mortality due to cardiovascular-related medical conditions.
“Having a dog was associated with increased physical exercise, lower blood pressure levels and better cholesterol profile in previous reports,” said Caroline Kramer, M.D. Ph.D., Assistant Professor of Medicine at the University of Toronto. “As such, the findings that people who owned dogs lived longer and their risk for cardiovascular death was also lower are somewhat expected.”
“Our findings suggest that having a dog is associated with longer life. Our analyses did not account for confounders such as better fitness or an overall healthier lifestyle that could be associated with dog ownership. The results, however, were very positive,” Dr. Kramer added.
“The next step on this topic would be an interventional study to evaluate cardiovascular outcomes after adopting a dog and the social and psychological benefits of dog ownership. As a dog owner myself, I can say that adopting Romeo (the author’s miniature Schnauzer) has increased my steps and physical activity each day, and he has filled my daily routine with joy and unconditional love.”
Rabies is a virus that is usually spread by a bite or scratch from an infected animal. The virus attacks the central nervous system and can cause inflammation in the brain, eventually leading to death. In principle, no human today should die from rabies, and yet rabies is responsible for an estimated 59,000 human deaths and over 3.7 million disability-adjusted life years (DALYs) lost every year.
That total is not as high as the death toll from tuberculosis, HIV/AIDS, and malaria; but, unlike those diseases, rabies seems able to infect all and every mammal species we know of. Dogs, the predominant host in most regions, can become infected from any rabid wild animal, and then infect humans.
The World Health Organization has made it a goal to eliminate human rabies deaths due to dog bites by the year 2030. An increase in dog rabies vaccination rates decreases dog rabies cases, human exposure, and human deaths, according to a new article in PLOS Neglected Tropical Diseases.
Implementing the goal of rabies elimination requires understanding the complex interaction between dog rabies vaccinations and human risk and response. Between 1995 and 2005, there was a rapid decline in dog and human rabies cases in seven Latin American countries following investments in both dog vaccination programs and human post-exposure prophylaxis (PEP) use.
New research by investigators from the School of Economic Sciences and the Paul G. Allen School for Global Animal Health at Washington State University, analyzed data from those seven countries — Brazil, Colombia, Peru, Venezuela, Nicaragua, Dominican Republic and Mexico. The data, compiled from reports published by the Reunión de Directores de los Programas de Rabia de las Américas (REDIPRA) from 1995 through 2006, included rates of dog vaccinations, dog rabies cases, reported human exposures, human PEP use, and human rabies cases.
The researchers found that a 10% increase in dog rabies vaccination rates decreases cases of dog rabies 2.3%. They add that this leads to a decline in how often humans are exposed to cases of rabies. At the same time, however, the reported number of cases of rabies stays constant or even increases — as more people report exposure to the same infected animal “which may result from higher rabies awareness due to anti-rabies campaigns,” the team notes.
While human exposures decline as dog rabies cases decline, exposures per dog rabies case increase, likely due to increased awareness. In addition, a 10% increase in dog vaccination leads to a 2.8% decrease in PEP use, and each 10% increase in PEP use decreases human deaths by 7%. Overall, a 10% increase in dog vaccination reduces human deaths by 12.4%.
“The findings highlight the critical importance of mass dog vaccination, heightened public awareness, treatment access, and the use of clinical algorithms to reduce both false negatives leading to death and false positives leading to costly unnecessary PEP prescriptions,” the researchers say.
World Rabies Day, observed on September 28 every year, aims to raise awareness about rabies prevention as well as highlight progress in defeating this horrifying disease. The day also marks the death anniversary of Louis Pasteur, the French chemist and microbiologist, who developed the first rabies vaccine.
Humans and dogs share a special relationship. For better or worse, dogs have become entirely reliant on their human masters, who’ve not only shaped the canine species but also countless breeds. A new study shows how vastly different the brains of man’s best friend can be from breed to breed.
If you love dogs, you might be aware that Labrador retrievers are friendly, Dalmatians are hyper, and Australian shepherds are smart. These are no accidents — these characteristics, or phenotypes, have been selected by dog breeders over the centuries, or are the unintended result of chasing some other particular characteristic.
For instance, Dalmatians were originally meant to service humans as coach dogs due to their comfort around horses. In time, Dalmatians grew into a breed known for its endurance, being able to run alongside a horse-drawn carriage for days. However, in a modern home, a Dalmatian’s excess of energy can lead to less desirable behaviors, such as chewing shoes and destroying the furniture.
Erin Hecht and colleagues wanted to investigate what were some of the effects of this selective pressure on the brains of dogs. With this in mind, they performed magnetic resonance imaging scans on 33 dog breeds.
The results suggest that there’s a wide variation in brain structure that couldn’t be accounted for simply by body size or head shape.
Some brain areas exhibited more variation across breeds. The researchers were able to generate the maps of six brain networks with functions ranging from social bonding to movement. Each network was associated with at least one behavioral characteristic.
These neuroanatomical variations are fascinating, offering a unique glimpse into the evolutionary relationship between brain structure and animal behavior.
Dog owners are more likely to exercise and they’re also more likely to have better heart health, a new study shows.
A heart’s best friend
Humans have co-evolved with dogs for tens of thousands of years. Over the course of our common history, both we and our canine friends have changed quite a bit — and our relationship has also shifted. Most often, dog owners nowadays walk their pets a couple of times a day, which means they are more physically active and, consequently, have better health.
This idea has been confirmed in a new study.
The study traced health metrics from 1,700 people participating in the Kardiozive Brno 2030 study, which followed 1% of the population in the city of Brno, Czech Republic. The study analyzed various measures related to cardiovascular health: body mass index, diet, physical activity, smoking status, blood pressure, blood glucose, and total cholesterol. The study also compared pet ownership with the measured health metrics.
All pet ownership was linked to better cardiovascular health, but the results were most noticeable for dog owners.
Study co-author Andrea Maugeri, a researcher with the International Clinical Research Center at St. Anne’s University Hospital in Brno and Italy’s University of Catania, commented in a statement:
“In general, people who owned any pet were more likely to report more physical activity, better diet and blood sugar at ideal level.”
As more and more people are suffering from cardiovascular diseases, pet ownership can be an important and beneficial intervention.
Surprisingly, the data also found that dog owners are more likely to be smokers, which overshadows the positive effects associated with dog ownership — although this might be skewed by cultural factors, as smoking is quite prevalent in the Czech Republic.
This isn’t the first study to conclude that dog ownership improves cardiovascular and mental health. A landmark study from Sweden analyzed the effects of dog ownership on a nationwide cohort of 3,432,153 individuals, with 12 years of follow-up. The benefits were especially impressive for single-person households, where dog ownership was associated with lower risks of both all-cause mortality and CVD mortality (33% and 36% reductions, respectively). People living in multiple-person households also benefited from dog ownership with significantly lower risks of all-cause mortality and CVD mortality (11% and 15% reductions, respectively).
However, there’s an important question here: do dogs make owners healthier, or are healthier people more likely to adopt a dog in the first place? The answer to that question isn’t entirely clear, but the evidence seems to support the former, says Jose Medina-Inojosa, M.D., one of the study authors. Furthermore, one recent study published last year in the journalBMC Psychiatry looking at 17 existing papers concluded that having a pet could ease symptoms of mental illness.
In other words, if you’re on the fence about adopting a furry friend, you can add “improving health” to the list of advantages.
A commercial breeding facility for small dogs in Marion County, Iowa, has been quarantined by state officials. According to veterinarians, the facility in southeast Iowa is the source of several cases of canine brucellosis — a dangerous disease that causes infertility problems and is transmissible to humans.
The Iowa Department of Agriculture and Land Stewardship has notified the owners of exposed dogs and has instated a 30-day quarantine on both the animals and the breeding facilities until the animals undergo thorough testing. It’s not clear at this moment how many dogs have been infected, although AHeinz57 Pet Rescue & Transport, Inc., which is based in De Soto, Iowa, said it has quarantined about 32 dogs from a breeder in relation to the disease.
“We are in the process of notifying the individuals who have custody of the exposed dogs,” the department explained in a press release. “Both the animals and the facilities are quarantined while the dogs undergo clinical testing.”
Canine brucellosis is a highly contagious disease that affects the reproductive tract of dogs, causing infertility, stillbirths, and spontaneous abortions. Although it happens very rarely, sometimes the disease can pass to humans causing flu-like symptoms such as fever, joint pain, headaches, and sweats.
If a pregnant woman is infected with the disease, perhaps due to contact with her pet dog, it can cause a miscarriage or force the woman to give birth prematurely.
There is no cure for canine brucellosis. What’s more, infected dogs may appear to be healthy, despite carrying the disease. This is why it’s standard procedure for dogs who are tested positive to be put down.
According to the state department, citizens shouldn’t panic as most pet owners are not at risk. The people most vulnerable to the disease are dog breeders, veterinary staff, and anyone who comes in contact with tissue and fluids during a canine birth.
As if dogs weren’t precious enough, they also help with our fitness — new research shows that dog owners are 400% more likely to meet recommended physical activity guidelines.
Dog owners were found to walk their dogs for a median 7.0 times per week (range 0–32), covering a median total of 220.0mins per week.
The fact that dog owners tend to do more exercise shouldn’t really surprise anyone — whether you like it or not, you have to go walk the dog. However, previous research mostly focused on a single household member, and it’s not exactly clear whether time spent dog walking replaces other physical activity. In the latest study, researchers analyzed just what kind of a difference having a dog really makes — fitness-wise.
Carri Westgarth and colleagues from the University of Liverpool assessed the self-reported physical activity of 385 households in the, UK (191 dog owning adults, 455 non-dog owning adults and 46 children). Researchers also tracked 28 adults with an accelerometer, to have a confirmation for the total physical activity.
They found that dog owners walk more frequently and for longer periods than non-dog owners — and this activity doesn’t replace other physical activities. In other words, it’s simply extra physical activity. Researchers were able to confirm the health-enhancing potential of dog ownership.
“Evidence suggests dog ownership is associated with lower risk of death, and a lower risk of cardiovascular conditions at least in single-person households, where the participant may be more highly obligated to dog walk,” the study reads.
For many people, this could be the difference between healthy and unhealthy levels of exercise. Researchers recommend doing at least 150 minutes of moderate-to-vigorous physical activity per week. However, less than 50% of adults in the USA actually achieve this. England fares a bit better, but still, only 66% of men and 58% of women achieve this bare minimum goal. This study found that dog owners were four times more likely to achieve this goal. Furthermore, the benefits extend to all household members involved in dog-walking.
The results are so positive that researchers actually call for policy to support more dog ownership, considering the health benefits associated with it.
“Dog ownership is associated with more recreational walking and considerably greater odds of meeting physical activity guidelines. Policies regarding public spaces and housing should support dog ownership due to physical activity benefts,” the team writes.
So if you’re struggling to lose weight or be physically active, there’s a woofing solution to that.
The study “Dog owners are more likely to meet physical activity guidelines than people without a dog: An investigation of the association between dog ownership and physical activity levels in a UK community” has been published in Scientific Reports.
Dogs are not only man’s best friend, but they’re also amazing sniffers. Their ability to detect explosives or illegal substances has long been understood but we’re just scratching the surface. Recent studies have shown that dogs are able to detect several types of cancer, malaria, and even so-called superbugs. Researchers are now trying to find new ways to replicate these abilities in sensors and robots.
“We turned to animals to understand what nature has already figured out,” said Thomas Spencer, a doctoral candidate in David Hu’s lab at Georgia Tech. “We are applying the underlying principles that we learned about these mechanisms to design a better sensor.”
An electronic nose
Spencer and colleagues work on designing the electronic equivalent of a nose — and they started out with a cheese smelling competition — how else? At the current stage, the team focused on how to best drive the odor to the sensor, a natural process in the biological world, but one that’s quite tricky to replicate electronically.
Dogs aren’t the only creatures with amazing sniffing abilities, and researchers wanted to see which animals fare best in this regard. To this aim, they traveled to the Atlanta Zoo to compare the way different animals sniff, from mice to elephants.
“We wanted to measure the sniffing frequency of animals when they are trying to identify a new source of food or something that interests them,” Spencer said.
Unsurprisingly, they found that sniffing speed decreases with body size — in other words, small creatures like mice sniff much faster than large creatures like elephants.
In order to figure this out, the team used wind tunnel experiments to map how the odor particles moved through the air. The team gathered sensor information in real time, analyzing how chemical compounds shift around during the sniffing process and then developed computer simulations to refine the observations.
“These findings are important because it gives us insight into the physics of sniffing,” said Hu, an associate professor of mechanical engineering and biology at Georgia Tech. “This information will affect how we scale up sniffing machines.”
Kelly the elephant searching for food above eye level using her trunk. Image credits: Thomas Spencer.
Using these insights, they were able to design an electronic nose that distinguishes from different types of cheese — still a far cry from what dogs can do, but a great step in the right direction.
So far, results are only preliminary and have not been published in a peer-reviewed journal. The study will be presented at American Physical Society’s Division of Fluid Dynamics 71st Annual Meeting.
“This is still a fairly new study,” Spencer said. “Our hope is to get a snippet of that ability and replicate it for ourselves.”
Dogs have showcased their amazing sniffing abilities once again — this time, by identifying malaria cases on the spot and aiding or potentially replacing more expensive and time-consuming tests.
Freya, a Springer Spaniel, is among the dogs who have been trained to sniff out the scent of malaria. Freya’s highly sensitive nose could help provide the first non-invasive test for malaria. Sniffer dogs could potentially be deployed at ports of entry to identify passengers carrying malaria to prevent the spread of the disease across borders and to ensure people receive timely antimalarial treatment. Image credits: Medical Detection Dogs.
The fight against malaria took massive strides from 2000 to 2015, when fatalities were reduced by more than 60 percent, saving almost 7 million lives and preventing more than 1 billion malaria cases. But things have somewhat stagnated.
This is where man’s best friend steps in.
There are several tests for malaria, generally consisting of a blood test. Now, researchers have shown that a simple dog sniff could work equally well, simplifying things and offering a low-cost alternative. It’s also the first non-invasive diagnosis available for malaria.
“People with malaria parasites generate distinct odors on their skin and our study found dogs, which have an incredibly sensitive sense of smell, can be trained to detect these odors even when it’s just on an article of clothing worn by an infected person,” said Steven Lindsay, a public health entomologist at in the Department of Biosciences at Durham University in the United Kingdom and the lead investigator on the study.
The test worked by having dogs sniff children’s’ socks, and was generally effective, though not flawless. Overall, 175 sock samples were from 30 malaria-positive children and 145 from uninfected children (as verified with conventional tests). The dogs were successful in identifying 70% of the malaria-infected samples and 90% of the samples without malaria parasites.
Lindsay also adds that the dogs’ accuracy rate was slightly lowered because some children were carrying different types of malaria parasites. The accuracy rate could also be improved if the dogs are trained with fresh samples, instead of samples which were frozen over the duration of the training course (as was the case now).
Overall, with a bit more finessed training, the dogs could ultimately reach a level comparable to existing medical tests.
“While our findings are at an early stage, in principle we have shown that dogs could be trained to detect malaria infected people by their odour with a credible degree of accuracy,” says Professor Steve Lindsay, lead author. “This could provide a non-invasive way of screening for the disease at ports of entry in a similar way to how sniffer dogs are routinely used to detect fruit and vegetables or drugs at airports.”
“This could help prevent the spread of malaria to countries that have been declared malaria free and also ensure that people, many of whom might be unaware that they are infected with the malaria parasite, receive antimalarial drug treatment for the disease.”
Even if the dogs are a bit less accurate than medical tests, Lindsay said detection dogs could be used for narrowing the focus of clinical testing and treatment efforts. Detection dogs would operate best at ports of entry into countries which eliminated malaria or are close to elimination, as a sort of safety barrier. In the fight against malaria, we need all the help we can get.
Malaria is still one of the most dangerous diseases in the world. According to the World Malaria Report 2016, there were 212 million cases of malaria globally in 2015 and 429,000 malaria deaths. These figures have remained somewhat constant in the past few years.
The findings will be presented at the 67th American Society of Tropical Medicine and Hygiene (ASTMH) Annual Meeting. The research was funded by the Bill & Melinda Gates Foundation.
A dog named Monty is the newest hot topic among archaeologists in the Czech Republic.
The items Monty unearthed. Image credits Hradec Králové Region.
Back in March, Monty was out on a walk in the Orlické Mountains (northeastern Bohemia) with his owner, Mr. Frankota, when he made a stunning discovery: a cache of Bronze Age artifacts. The objects unearthed by the pet are in a “surprisingly” good state, archeologists report.
Frankota recounts that Monty rushed off during their walk and started digging frantically. He walked over to check what got his dog so excited and was surprised to see a collection of bronze objects. The stash — which has been donated to the Hradec Králové Region local government — contained 13 sickle blades, 3 axe blades, and two spearheads.
All items were fashioned out of bronze. The wealth of objects, as well as the excellent condition they were buried in, points to a ritual deposit, archeologists believe.
“What particularly surprised us was that the objects were whole, because the culture that lived here at the time normally just buried fragments, often melted as well. These objects are beautiful, but the fact that they are complete and in good condition is of much more value to us.”
Beková was part of the team that examined the artifacts after Frankota delivered them to local authorities. They were likely produced by the Urnfield culture, a late Bronze Age Indo-European people that lived in the area. Their name stems from the group’s mortuary practices: they would cremate their dead and bury them in urns in fields.
As of now, the team cannot say for sure how or why the items were buried in the area.
The discovery has local archeologists excited — and rightly so. It’s the largest single finding in the region. They’re currently combing the region with metal detects but, so far, their search proved unfruitful. Still, they’re not about to give up just yet.
“There were some considerable changes to the surrounding terrain over the centuries, so it is possible that the deeper layers are still hiding some secrets,” Sylvie Velčovská from the local regional council.
The artifacts are currently on display as part of the exhibition Journey to the Beginning of Time at the Museum and Gallery of Orlické Mountains, Rychnov, until 21 October 2018. After that, they will undergo conservation and be moved to a permanent exhibition in a museum in Kostelec.
The team also wants to point out that archeologists often work with lucky discoveries made by members of the public or during excavation works; if you happen to stumble into some artifacts, you should notify local authorities (archeological items are considered government property in most states). It’s not a one-sided deal, either: Frankota was awarded 7,860 CZK (roughly US$360) for the items.
Hopefully, some of that will go towards buying Monty some well-deserved treats.
People have had a close bond with domesticated dogs for centuries. In his 1764 Dictionnaire philosophique, Voltaire observed: “It seems that nature has given the dog to man for his defence and for his pleasure. Of all the animals it is the most faithful: it is the best friend man can have.”
Research has shown time and time again the positive impact pet ownership can have on our lives. Indeed, a study of 975 dog-owning adults, found that in times of emotional distress most people were more likely to turn to their dogs than their mothers, fathers, siblings, best friends, or children.
It’s not surprising then that dogs are now the most commonly used animal in therapy. Our canine pals are being increasingly used as participants in a variety of mental health programmes – offering companionship, happy associations and unconditional love.
In the UK, Pets As Therapy (PAT) has more than 5,000 active PAT dogs, which meet some 130,000 people a week. In the US, the American Kennel Club has a Therapy Dog Program which recognises six national therapy dog organisations and awards official titles to dogs who have worked to improve the lives of the people they have visited.
Dogs who heal
Sigmund Freud is generally acknowledged as the accidental pioneer of canine-assisted therapy. During his psychotherapy sessions in the 1930s, a chow chow called Jofi stayed alongside him in the office. Freud noticed that patients became more relaxed and open when Jofi was present, and it helped him to build a rapport.
Despite all this, it was not until the 1960s that the first documented case study of a dog working as a “co-therapist” was made. The US psychotherapist Boris M. Levinson maintained that the presence of his dog Jingles added a “new dimension to child psychotherapy”. Despite opposition from peers, Levinson strongly defended the use of dogs as therapeutic aids.
How dogs feel
But while there is no question that dogs are very good at understanding us, sadly the reverse is not always so true. A classic example of this is when someone has had a little “accident” in the house and dog owners think that their pet looks guilty. But for the dog in question, that look is purely submission and is a way for the dog to say “don’t hurt me” rather than an admission of guilt.
It is very difficult for humans to convince themselves that the canine brain is not able to understand the concepts of right and wrong – but without that ability it is not possible to experience guilt. The dog who is looking guilty is simply afraid of your reaction to the situation – usually based on past experience.
Some of the main difficulties that happen between dogs and their owners are caused by a humans inability to read their pet’s body language correctly. Combine this with the human notion that dogs understand abstract concepts and can use reason on complex issues, and the scene is set for problems.
Another way to tell how animals feel is to look at their hormonal environment. Studies have shown that when dogs are stroked by their owners they have increased levels of oxytocin. Among other functions, this hormone is thought to help relaxation. It helps to form bonds between mother and child – and between pet and owner.
So although we can’t know for sure how a dog feels during pleasurable activities, it seems reasonable that oxytocin produces similar sensations in dogs to those that humans experience – suggesting that they are feeling affection towards and attachment to their owners.
Similarly, dogs that are in unpleasant circumstances show raised levels of the stress hormone, cortisol. One of the situations that produces this stress response is being left alone for any length of time. Dogs are pack animals and really need to have company. A solitary dog is rarely a happy dog – and this is something that all dog owners should take into account when planning their lives.
What this all shows is that for dogs and people to live together and work together – and for both parties to be happy about it – an understanding of each other’s emotional state is vital. Even if dogs and people don’t completely understand each other, it seems clear that each species is essential to the other’s well-being and we can help each other to be happier and healthier.