Dogs get jealous and 19 other facts you probably never knew about man's best friend
Do our four-legged friends really see in black and white and what does it actually mean when they're wagging their tails?
Dogs suffer from jealousy and are just as likely to turn into a green eyed monster as humans, according to scientists in California.
Researchers studied 36 dogs from 14 breeds and found that most were indifferent when their owners ignored them until the owners showered their attention on a stuffed dog.
Then the pet pooches' behaviour changed dramatically, sparking snapping and snarling. The discovery shows that while dogs are man’s best friend, they still have the capacity to surprise us.
Here are some other facts you might not know about Fido.
1) Dogs don’t feel guilt
Scientists believe dogs can experience jealousy when their owners give attention to other dogs. But if they eat every biscuit in the house, they may look ashamed but don’t expect them to feel guilty as they don’t experience these emotions.
Researchers found those puppy dog eyes are not a sign of guilt. In fact they are just the way we interpret a dog’s reaction to being scolded.
Alexandra Horowitz, from Barnard College in New York found all dogs looked ‘guilty’ after being told off for eating a forbidden treat like a biscuit - and those who were wrongly accused often looked more ‘guilty’ than those who really deserved to be in the dog house.
Maybe Denver didn't eat the kitty treats after all...
2) Dog urine can corrode metal
Apparently allowing your dog to wee on a lamp-post could be more dangerous than you think - because the acids in the urine can corrode the metal.
In April 2003 Derbyshire County Council spent £75,000 carrying out a six month survey of one million lamp-posts amid fears that dog wee was causing the bases to crumple. In the same year, urinating dogs were blamed for a spate of lamp-posts collapsing in Croatia.
We dread to think what damage this mutt did to this Banksy mural in New York then.
3) Dogs can see in colour
It is a common myth that dogs can only see in black and white but they can actually see colours - just not as vividly as humans.
They only have two cones in their eyes to detect colours, whereas humans have three. That means dogs see colours on a blue and yellow scale but cannot distinguish between red and green. On the other hand, they have better night vision than humans.
Dogs also see in a kind of slow motion. Their eyes take in information more than 25% faster than us, making them extra talented at catching a ball or frisbee in the park.
4) No compass needed
Dogs can see UV light, and don’t need a compass because they can sense the earth’s magnetic fields. It’s believed they can hear some of the ultrasound waves that bats use to navigate in the dark.
5) Their sense of smell is REALLY powerful
We know dogs have a powerful sense of smell and while we can just about smell a spoonful of sugar in a cup of tea, our canine friends are capable of smelling that same spoonful in two Olympic swimming pools’ worth of water.
6) In fact, they can smell disease
If your canine chum is acting strange there might be nothing wrong with them - the problem could be with you.
Research at the Schillerhohe Hospital in Germany found dogs have an incredible ability to recognise the smell of a range of organic compounds that show the human body isn’t working as it should.
That means your dog can actually diagnose your cancer, something scientists are eager to explore further, as well as diabetes and the early signs of an epileptic seizure.
7) Dogs can be pretty smart
You might sometimes think your dog is as daft as a brush, but the truth is that they can actually be as smart as a two year-old child, according to research presented to the American Psychological Association.
Dogs can understand up to 250 words and gestures and even perform simple mathematical calculations.
Perhaps unsurprisingly, border collies are the cleverest canines, with some able to understand up to 200 words. The other breeds in the top five are poodles, German shepherds, golden retrievers and dobermans.
Don't believe us? Just look at what Nana can do...
Ever wondered why your dog ignores your commands when you are in your local park? Researchers found that dogs disregard bad advice from their owners. Dogs will leave out unnecessary actions if they have learned there’s a more efficient way to solve the task.
Dogs understand fairness, and will refuse to play ball when asked to carry out a trick if they are not offered the same reward as a fellow dog for equal work.
8) A wagging tail doesn’t always mean they are happy
Tail wagging has its own language. Apparently dogs wag their tail to the right when they’re happy and to the left when they are frightened. Wagging low means they are insecure and rapid movements accompanied by tense muscles or dilated pupils can signal agression.
So every wagging tail tells its own story, if you know how to read the signs.
9) They really are hot dogs
Next time you see your pet pooch panting on a sunny day take pity on them. Not only are they wearing a huge fur coat, they also have to contend with a higher body temperature than you.
The normal body temperature of a human is 37ºC, but a dog’s is a whole degree higher at 38ºC. That’s one reason fleas are more likely to be attracted to your dog than to you. And unlike humans, dogs don’t have sweat glands all over their body, just on the pads of their paws.
10) Dogs have their own ‘fingerprint’
A dog’s paw print may look pretty generic but their nose print is actually as unique as a human fingerprint. Their combination of ridges and creases is so distinct it can actually be used to identify them.
Good luck getting them to stick their nose in a pad of ink without sneezing though.
11) ...and other weird bodily functions
Unlike humans, dogs’ shoulder blades are not attached to the skeleton, allowing for greater flexibility for running.
They mainly sweat from the bottom of their feet as most of their sweat glands are located around the foot pads.
They also have a third eyelid, or nictitating membrane, which helps to keep their eyes moist.
Dogs can shake 70% of the water out of their fur in four seconds, generating more G-force than F1 drivers experience in sharp corners.
12) Dogs dream just like you
This won’t come as a huge surprise to anyone who has watched their own dog twitching or whimpering in their sleep. Dogs have the same brain wave patterns while they are asleep as humans, so they dream just like we do.
But what is more surprising is the fact that not all dogs dream the same amount. Small dogs actually have more dreams than big dogs. For example, a small dog such as a toy poodle may dream once every 10 minutes, whereas a great dane may have around an hour between each dream.
13) Dogs can fall in love
They don't call it puppy love for nothing. The concept that dogs can fall in love was suggested by anthropologist Elizabeth Marshall Thomas, author of The Social Lives of Dogs, who believed two dogs named Sundog and Bean were agonized star-crossed lovers kept apart because neither of their owners wanted to give them up.
It may sound far fetched but Paul Zak, a professor at Claremont Graduate University in California, found that a dog’s brain releases oxytocin - the love hormone - when it interacts with humans and dogs, just the same as a human brain does when we hug or kiss.
14) How and why they became 'man's best friend'
Scientists believe that humans and dogs first became best friends 30,000 years ago and our close bond started in Ice Age Europe when wolves, ancestors of today’s domesticated dogs, were first tamed by the ancient hunter gatherers.
They are known as man’s best friend for good reason. Research shows that dogs are more confident exploring the world when they have their owner, rather than anyone else, by their side.
Scientists have found that their owners’ smell actually sparks activation in the “reward centre” of dogs’ brains and our odour lingers there like a perfume, triggering an instinctive emotional response. Now we know why our pets are so pleased to see us.
15) Think you look like your dog? Here's why...
Pet dogs have been shown to match their owners in both personality and looks. Some psychologists believe this might have spilled over from the way we evolved to find mates – by choosing a mate who looks like you, it may ensure their genes are compatible with your own.
Dogs respond to the sound of a human crying with the same part of their brain that responds to whining dogs, MRI scans show. Dogs can also “catch” yawns from humans, but a study has shown that they are five times more likely to do so if the yawn comes from their owner, which suggests canines can empathise with people.
16) Poodles' hairstyles aren't just for looking good
Poodles ’ hair styles may seem like a fashion statement, but they were originally clipped to make them better swimmers. They dogs were bred to retrieve game from water and the bottom half of the body was shorn to make them more buoyant.
17) Watch out for Shih Tzus
They may be dinky and cuter than a newborn baby, but Shih Tzus are one of the breeds most closely related to the wolf.
18) Ever wondered why they're so cute?
Ever wonder why you find it impossible to resist when your pooch pleads for a treat? Well, dogs exhibit “neoteny”, which means they retain baby-like features, such as large eyes and playful behaviour, long into adulthood. And it’s thought we selected them for this – essentially to be cuter.
19) Some dogs are more rare than pandas
The Dandie Dinmont Terrier is now considered rarer than the giant panda. The British breed was named after a character created by Sir Walter Scott in his novel Guy Mannering.
Thanks to the popularity of the book, they became fashionable and famous Dandie Dinmont owners included Queen Victoria.
20) Right-pawed or left-pawed?
About 90% of humans are right-handed, with most of the rest left-handed and a very small percentage ambidextrous. But dogs are more evenly split, with one third right-pawed, one third left-pawed and the rest without preference. Dogs who are right-footed are more likely to pass the Guide Dog Training Programme than south paws. Research shows right-handed animals tend to be bolder and more inquisitive so are more suited to being a guide dog. Left-handed dogs also tend to be more aggressive.
Original text by Mirror Online