Tag: ZME Science website

Speaking with wolves!

An insightful look at the way that baby wolves play.

I’m gradually getting ourselves organised following the power failure and, on cue, Chris Gomez sent the following in two days ago.

It shows beyond doubt that young wolves play like dogs and that the two animals are more alike than dis-alike.

You watch the following video and see what I mean.

Then there is the article that is reproduced below.

ooOOoo

Baby wolves like to play fetch too – what this says about your dog.

By Fermin Koop

Playing a game of fetch with a dog means they are following a human social cue to recover the ball. But fetch isn’t just for dogs, wolf puppies are down to play too, which means they can also understand human communication cues, according to a new study.

Credit Wikipedia Commons

The findings, published in the journal iScience, were made after researchers put 13 8-week-old wolf puppies from three different litters through a series of tests usually used to assess dog-puppy behavior. Three of the pups were interested in playing fetch with a stranger, which included bringing a ball back when encouraged to.

The discovery was quite a surprise for the team as it was believed that the cognitive abilities necessary to understand communication cues given by a human were presented in dogs only after humans domesticated them 15,000 years ago. Dogs differ from wolves physically, genetically and behaviorally.

“When I saw the first wolf puppy retrieving the ball, I literally got goosebumps,” said Christina Hansen Wheat of Stockholm University in a press release. “I immediately knew that this meant that if variation in human-directed play behavior exists in wolves, this behavior could have been a potential target for early selective pressures exerted during dog domestication.”

Wanting to learn more about the effects of domestication on behavior, Hansen Wheat and her team raised wolf and dog puppies from the age of 10 days and put them through various behavioral tests. In one of them, the pup was thrown a ball by an unknown person, encouraging the wolf to get it and bring it back.

Expectations of the wolf pups catching on weren’t high, with the first two litters showing no interest in the balls, let alone of playing fetch. But everything changed with the third litter. A few of the puppies went for the ball and even responded to the social cues and brought it back.

“It was very surprising that we had wolves actually retrieving the ball,” said Hansen Wheat. “I did not expect that. I do not think any of us did. It was especially surprising that the wolves retrieved the ball for a person they had never met before.”

In the past, other research showed that domesticated and non-domesticated species will follow human gestures if a food reward is given, Hansen Wheat and her team said. But in those cases, the animals were previously trained to follow the cues or knew the person conducting the study.

While the new research has a limitation over the size of its sample, it could reassess our interpretation that understanding human social cues came from domestication. Instead, it could be possible that this behavior can be traced back to an ancestral population before wolves were domesticated into dogs.

ooOOoo

Despite this being the twenty-first century there are still things being discovered that cause us humans to be amazed.

Such as this story about the young wolves, way before they evolved into dogs.

There’s more to a dog’s whiskers than we imagined!

A fascinating article.

The following was sent to me by Chris Gomez, brother of Dan, who I have known for nearly as long as Dan (and that’s a long time)!

The article appeared on ZME Science was published on the 15th January. It contains material that I, for one, didn’t know and I suspect I’m not the only one.

Have a read.

ooOOoo

Why do dogs have whiskers?

Whiskers allow dogs to “see” things that are literally under their noses.

By Tibi Puiu

Credit: Pixabay

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

Credit: Wikimedia Commons.

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

Credit: Pxfuel.

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.

ooOOoo

Apart from the fact that the photographs are gorgeous there is much material that is good to know. For instance, I never knew there were no breed-specific differences in canine whiskers. Just hadn’t thought about it before.

Thank you, Chris, for a great link!

How old is your dog?

Dan sends me a more accurate calculation.

Dear Dan and I recently had an email ‘conversation’ about the conversion of dog years to human years. Then, yesterday,  as in Thursday, he sent me the following article from ZME Science.

Enjoy!

ooOOoo

Here’s a better way to calculate dog years – backed by science.

Lets’s face it, 1 for 7 years is not accurate.

November 21, 2019

By Mihai Andrei

The formula is about mid-way through the article, and it includes a simple calculator.

We learn, as kids, to approximate dog age thusly: one dog year for seven human years. That’s a decent approximation in some cases, but the more you think about it, the more it starts to fall apart.

All dog breeds tend to follow a similar pattern: they reach puberty at 10 months old. Right off the bat, it’s clear that the approximation doesn’t work here, as humans don’t really reach puberty at 6 years. Dogs can also reach 20 years or even more, and 140 years has never been recorded for a human. All in all, while it can give a ballpark estimate, the 7-for-1 approach falls short in many regards.

But now, researchers have come up with a much more accurate formula to assess dog age in human years. This one, at least, is backed by science.

It started as a way to detect factors associated with dog aging, and it focused on a relatively new concept: DNA methylation. The idea is that as we age, our DNA undergoes chemical modifications which can be used as a sort of genetic clock. It’s a way of looking at our body’s wear and tear, as the influence of diseases and unhealthy lifestyle can also be observed (to an extent) with this approach.

It’s not just humans that have epigenetic clocks. Other species have them too — including dogs. Geneticist Trey Ideker of the University of California, San Diego, and colleagues, analyzed the DNA methylation patterns in the genomes of 104 dogs (all golden retrievers), ranging from 4 weeks to 16 years of age. Although just golden retrievers were analyzed, the patterns are very similar for all breeds.

There were remarkable similarities between the DNA methylation of dogs and humans. Although the two species diverged a very long time ago, dogs live in similar environments to humans, and they even have access to similar healthcare.

Simply put, the patterns of DNA methylation in young dogs tended to be similar to those in young humans — the same goes for older dogs and older humans.

Finally, the study also demonstrates that these patterns can be used to translate the age-related physiology of one organism (in this case, dogs) to another organism (humans).

The formula is not linear, and is not exactly simple, but here it is:

Human Years = 16 ln(Dog Years) + 31,

where ln is the natural logarithm.

Inputs

Dog_years:

Outputs

Human_years:

-∞

Powered by JSCalc.io

 

Logarithmic function for epigenetic translation from dog age (x-axis) to human age (y-axis). Tom Hanks for scale. Image credits: Wang et al

The natural logarithm is used because dogs and humans don’t age similarly. Dogs seem to age very quickly in the first part of their life (which is why the age of young pups seem very weird translated into human years), but their ageing process slows down massively compared to that of humans. So the translation dog to human years cannot be linear — it is logarithmic. When your dog is 1 year old, he’s approximately 30 in human years. When he’s 2 years old, he’s 42. He’s around 60 human years by the time he’s 6, but only 70 by the time he’s 12.

It’s a weird thing to wrap your mind around and it is definitely not a perfect translation from dog years to human years, but it works much better than all existing alternatives. It also works to explain why some dogs reach sexual adolescence as early as 6 months old — the onset for that is around 10-14 years for humans. Dogs are adolescent until about 2 years, which in humans lasts until 25 years old. Then, maturity for dogs is around 2-7 years, and for humans around 25-50 years. Similar calculations (but with a slightly different formula) can be carried out for other animals, including cats and mice, researchers conclude.

The study can be read in its entirety for free on biorXiv.

ooOOoo

M’mmm, I think I need a little more time to absorb that!

The smell of the North

The things science unearths!

Having nine dogs here at home and quite a few acres of land, you can easily imagine that one needs to keep a good lookout for the numerous ‘land mines’.

But as much as they are a common and familiar sight, especially around the house, never in a thousand years would I have noticed a magnetic alignment!

All brought to my awareness by a wonderful article over on the ZME Science website.

Are you a dog lover? Did you know this?

ooOOoo

Dogs can sense Earth’s magnetic field… while pooping

Jenny Ricken / Univ. of Duisberg-Essen via AFP – Getty Images
Jenny Ricken / Univ. of Duisberg-Essen via AFP – Getty Images

Every dog owner can attest that canines are remarkable navigators, like some sort of living, breathing compasses. For some time, researchers have suspected that they can sense Earth’s magnetic field and use it in turn for navigation. A recent study confirmed this as a fact, however the findings came after studying the dogs in one of their most intimate poses – while pooping. Apparently, in stable conditions, dogs always relieve themselves while facing either north or south.

Led by zoologist Hynek Burda of Germany’s University of Duisburg-Essen, the researchers closely followed 70 dogs of 37 breeds for two years. Initially, the dogs didn’t seem to follow any particular pattern while going on with their business. After taking in account, however, things like the time of the day, the position of the sun, wind direction and, of course, the slight daily variation in the Earth’s magnetic field a whole new level of appreciation was revealed.

“The emerging picture of the analysis of the categorized data is as clear as [it is] astounding: Dogs prefer alignment along the magnetic north-south axis, but only in periods of calm magnetic field conditions,” said Burda.

Alignment of a sampling of dogs while defecating during stable geomagnetic conditions. Photo: Hart et al. / Frontiers in Zoology
Alignment of a sampling of dogs while defecating during stable geomagnetic conditions. Photo: Hart et al. / Frontiers in Zoology

Poop compass

So, dogs will always poop or pee facing north or south during stable conditions. The study not only proves that dogs can sense the Earth’s magnetic field, but also exhibit specific behavior in response to natural magnetic field variations. To our current knowledge, they’re the only mammals that do this. Previously it was shown that cattle, deer, foxes and other types of mammals sometimes line up preferentially along Earth’s magnetic field lines.

To some, dogs’ “sixth sense” might not come as a surprise, while others may view the present study as a complete waste of grant money. While it’s still unclear how dogs use this skill, it may be too early to dismiss the practical applications of the findings. If anything, however, this research proves yet again that dogs are extraordinary animals.

“To many dog owners who know about the good navigation abilities of their protégés, the findings might not come as a surprise, but rather as an explanation for the ‘supernatural’ abilities—although it is not clear to the researchers what the dogs might use their magnetic sense for,” Burda said.

Next, the researchers plan on studying how dogs use this ability and how magnetic storms affect their ability to orient themselves. Findings were reported in the journal Frontiers in Zoology.

ooOOoo

To say that I’m just a tiny bit sceptical wouldn’t be a lie.  But, trust me, I shall be outside tomorrow morning with my compass and camera and will report the results!