Tag Archives: evolution

Dogs’ brains respond to human voices

Yet more research on how dogs’ brains work.  This time from a research team at Eötvös Loránd University in Hungary and published in the journal Current Biology.

Using functional MRI, the team could see where blood flowed in the brains of a group of 11 dogs.  The dogs had been specially trained using positive reinforcement techniques to lie still in the MRI scanner for six minutes.

A dog lies still in the fMRI scanner, wearing earphones to pipe in sounds as part of the study. (Photo by Eniko Kubinyi)

A dog lies still in the fMRI scanner, wearing earphones to pipe in sounds as part of the study. (Photo by Eniko Kubinyi)

which tracks blood flow to various areas of the brain, a sign of increased activity—to peer inside the minds of dogs. One of a handful of labs groups worldwide that’s using the technology in this way, they’ve used positive reinforcement training to get a study group of 11 dogs to voluntarily enter the fMRI scanner and stay perfectly still for minutes at a tRead more: http://www.smithsonianmag.com/science-nature/your-dog-can-tell-from-your-voice-if-youre-happy-or-sad-180949807/#DXcpTX0jfeQGFWVY.99
Give the gift of Smithsonian magazine for only $12! http://bit.ly/1cGUiGv
Follow us: @SmithsonianMag on Twitter

The team played each dog a series of over 200 sounds across several MRI sessions.  The sounds included human voices, dog vocalizations, and meaningless noises.

When the results were compared, it showed that the dogs’ brains appear to have a dedicated area that displays more activity in response to voices (whether human speech or dogs barking) than other meaningless noises (such as glass breaking).

More importantly, that part of the brain shows more activity upon hearing an emotionally positive sound, as compared to a negative one.  This means that our dogs are able to distinguish a tone of voice that is positive from one that is negative. (Something many of us probably already knew)

The voice areas of the dogs’ brains is similar to that found in humans, suggesting that our species evolved from a common ancestor almost 100 million years ago, enabling a high degree of communication and social structure.

“We know that dogs don’t have language, per se, but we see now that dogs have very similar mechanisms to process social information as humans,” Attila Andics, lead researcher on the study says. “It makes us wonder what aspects of so-called ‘language skills’ are not so human-specific after all, but are also there in other species. That’s something we plan to look at.”

Source:  Smithsonian Magazine

Here are my earlier blogs about functional MRI studies on dogs:

they show that the dogs’ brains appear to have a dedicated area that displays more activity in response to voices (whether human speech or dogs barking) than other meaningless noises (such as glass breaking), and that part of this area shows more activity upon hearing an emotionally positive sound, as compared to a negative one.Read more: http://www.smithsonianmag.com/science-nature/your-dog-can-tell-from-your-voice-if-youre-happy-or-sad-180949807/#DXcpTX0jfeQGFWVY.99
Give the gift of Smithsonian magazine for only $12! http://bit.ly/1cGUiGv
Follow us: @SmithsonianMag on Twitter
Advertisements

Adapting to the high altitudes of Tibet

In a new study published in the journal Molecular Biology and Evolution, author Dong-Dong Wu, et. al., explored the genetic basis of high-altitude adaptation of Tibetan Mastiffs, which were originally domesticated from the Chinese native dogs of the plains.

Credit: © zuzule / Fotolia

Credit: © zuzule / Fotolia

The authors examined genome-wide mutations (called single nucleotide polymorphisms, or SNPs) of 32 Tibetan Mastiffs, and compared them to 20 Chinese native dogs and 14 grey wolves. Overall, they identified more than 120,000 SNPs, and in their analysis, narrowed these down to 16 genes that have undergone positive selection in mastiffs, with 12 of these relevant to high altitude adaption.

These candidate genes have been shown to be involved in energy production critical to high-altitude survival under low oxygen conditions.

For future studies, the authors will explore whole genome sequences from individual Tibetan Mastiffs to gain better insights into high-altitude adaptations and canine evolution.

Source:  EurekAlert! media statement

Doing the dog paddle

If you have ever watched your dog swim, you’ve probably noticed that intense look of concentration on their face.  Research has confirmed that swimming doesn’t come as naturally as, say,  walking, running or trotting on land.

Photo by the Society for Integrative and Comparative Biology

Photo by the Society for Integrative and Comparative Biology

Dr. Frank Fish, a professor of biology at West Chester University, set out with his colleagues to understand how real dogs perform the dog paddle.

Dr Fish found a large horse rehabilitation pool for filming eight dogs of six different breeds during swimming.  Dr Fish’s own dog was one of the study subjects.

The team analyzed the videos and found that the dogs were swimming with a gait that was similar to a familiar trot on land. When a dog trots, moving at a pace more brisk than a walk, diagonal pairs of legs move together. In swimming, the dog’s legs move in a similar fashion, but even faster than a trot, and the legs move beyond the range of motion for a trot.  (This is one reason why I recommend swimming for many – but not all – of my massage and rehab customers.)

Swimming dogs are, essentially, using a basic movement but with some modification. Also, while the movements that make up terrestrial gaits like trotting can vary from one dog breed to another, the dog paddle gait showed very little variation among the different breeds.

Dr Fish says that dogs can be used as a model for precursors to early swimming mammals.   He hopes to unravel the steps in evolution that allowed four-legged terrestrial animals to become swimming mammals like the dolphin.

In the meantime, get out there and let your dog swim.   For most dogs, it’s great exercise!

Daisy concentrates during her swim at the Dog Swim Spa

Daisy concentrates during her swim at the Dog Swim Spa

Want to know more about physical rehabilitation and whether swimming is right for your dog?  Get in touch with me by completing the information below.

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition, Canine Catering Ltd, Christchurch, New Zealand

Source:  Society for Integrative and Comparative Biology media release

The ancestral roots of your dog

A genetic study by Peter Savolainen, a researcher in evolutionary genetics at KTH Royal Institute of Technology in Stockholm, has found that dog breeds from North and South America have Asian ancestry.

The Chihuahua definitely has Mexican heritage

The Chihuahua definitely has Mexican heritage

The native breeds have 30 percent or less modern replacement by European dogs.  It had been thought, prior to this study, that when Europeans settled in the American continent their dog breeds successively replaced the genetics of the native breeds.

Savolainen’s research group, in cooperation with colleagues in Portugal, compared mitochondrial DNA from Asian and European dogs, ancient American archaeological samples, and American dog breeds, including Chihuahuas, Peruvian hairless dogs and Arctic sled dogs.

They traced the American dogs’ ancestry back to East Asian and Siberian dogs, and also found direct relations between ancient American dogs and modern breeds.

The research confirmed conclusively that the modern day Chihuahua has Mexican roots.  The breed shares a DNA type uniquely with Mexican pre-Columbian samples.

The team also analysed stray dogs, confirming them generally to be runaway European dogs; but in Mexico and Bolivia they identified populations with high proportions of indigenous ancestry.

Source:  AlphaGalileo Foundation news release

Dog intelligence

Most dog owners have an opinion about their dog’s intelligence.  I regularly hear comments like, “He’s so smart, he’s ahead of the rest of his obedience class” or “He’s not very bright, but we love him.”

 When I was working on my management qualification years ago, we were told to go home and ask our partner/flatmate about how they solved problems.  Ebony, my Labrador flatmate at the time, came up with these tips, which I thought were very intelligent:

  1. Remember that chasing your tail does not get you anywhere.  It also makes you dizzy and less able to focus on the task at hand.
  2. Eat regularly and often.  Problem solving is hard work and requires energy.
  3. Don’t underestimate the value of a nap.  A problem looks different after you’ve had a good sleep.
  4. If you stare at a problem long enough, it might move on its own.
  5. Don’t be afraid to ask for help.  Try looking cute.
  6. If looking cute doesn’t work, try whining.
  7. If whining fails, loud retching noises are guaranteed to get the attention of those around you.
  8. Some problems soften over time.  Burying them in the garden hastens this process.
  9. Some problems require more immediate attention.  An immediate problem, if left unattended, is likely to result in a much more smelly mess to be cleaned up later.

There are many published works on the subject of dog intelligence.  Over the years, I’ve read countless research studies into this subject.  There are many institutions involved in the research.  All projects have the goal of understanding how dogs think.

Professor Stanley Coren of the University of British Columbia has authored several books about dog intelligence.  He states that dogs have the intellectual capacity of a two-year old and can understand more than 150 words.[1]

Researchers at the Max Planck Institute for Evolutionary Anthropology have studied the ability of dogs to interpret human gestures.  When researchers hid food beneath one container in a group and pointed to the ‘right’ container, dogs consistently picked up on those cues better than even chimpanzees (a species widely studied because of the evolutionary link between apes and humans).

Earlier this year, a research team at the University of Otago reported on their study that showed that dogs could readily distinguish happy human sounds from sad or angry ones, suggesting an ability to understand human emotions.

Even the dog toy market has recognised that dogs need mental stimulation.  The Nina Ottosson range, for example, offers a range of skill level toys designed to make your dog think about how to reveal their food reward.

Daisy demonstrates her intelligence with a Nina Ottosson toy

Despite all of this evidence, including videos of my Daisy using her interactive toys, many of the non-dog people in my life remain unconvinced about the intelligence of dogs.  I believe that persistence will pay off.  Over time we will see more and more research about the intellectual capacity of our dogs.  The non-believers will become believers.


[1] Science Daily, 10 August 2009