RESEARCH - Dogs May Have Been Domesticated Twice

(scienceagogo.com)

Scientists have theorized for years about when and where and how dogs were domesticated, without ever reaching a consensus.

Were they domesticated in East Eurasia and traveled west? In West Eurasia and traveled east? Where did they first become our companions, and how did our relationship with them develop?

These questions hold a lot of interest for scientists and for dog lovers, because our relationship with dogs is unique.

Not only are dogs an integral part of many people’s lives and critical in industries from farming to health care, they are also the only animal domesticated before the development of agriculture.

It’s possible that the reason scientists could never come to an agreement on the origin of domestic dogs is because they were each contributing a piece to a puzzle that is much bigger and covers much more geographical area than anyone anticipated.

Although domesticated animals are all around us – dogs, of course, but also horses, chickens, pigs, and others – the process of domestication is rare and complex. It doesn’t happen often, and no one understands exactly how it happens even though there are clues as to the when and where of it happening.

Now there is a better understanding of when and where it happened with dogs, and the answer isn’t East Eurasia or West Eurasia, the answer is both.

New research suggests that dogs were domesticated twice, at separate times and in separate locations, from two distinct wolf populations - once in Eastern Eurasia, and once in Western Eurasia.

The scientists combined ancient genetic material from 59 dog DNA fragments found across the European continent with 167 sequences of modern dog DNA.

They were able to sort these sequences, and determine that there was “clear turnover in the mitochondrial ancestry of European dogs,” meaning that at some point there was an introduction of new DNA in the European dog population. This new DNA came from East Asian dogs, dogs that had been domesticated from a separate wolf population.

In addition to the DNA evidence, the archaeological evidence also supports the idea of two distinct domestication events.

Dog remains have been found in Eastern Eurasian sites as old as 12,500 years, and in Western Eurasian sites as old as 15,000 years. But the oldest dog remains found in Central Eurasia are approximately 8000 years old.

This suggests that there was not a single cross-continental dog population, but rather two separate populations that eventually made their way into Central Eurasia.

The archaeological evidence has presented a challenge to the understanding of dog domestication for years, because although it had been theorized that dogs had been domesticated twice, there wasn’t supporting DNA evidence.

And, as Professor Greger Larson told Science Daily, “Animal domestication is a rare thing and a lot of evidence is required to overturn the assumption that it happened just once in any species.”

This finding provides the evidence to overturn that assumption, and offers insight into humans’ long relationship with dogs. 

By Tiffany Sostar

Tiffany is a writer, editor, academic, and animal lover who came late to her appreciation of pets. At 18, a rescue pup named Tasha saved her from a depression and she hasn't looked back. She has worked as the canine behaviour program coordinator for the Calgary Humane Society, and was a dog trainer specializing in working with fearful and reactive dogs for many years. She doesn't have any pets right now, but makes up for it by giving her petsitting clients (and any dogs she comes across on her frequent coffee shop adventures) extra snuggles.

RESEARCH - DNA Study Shows Inconsistent Identification of Pit Bulls

A recent survey shows shelter staff are inconsistent and often incorrect when it comes to identifying a dog's breed - a potentially devastating, if not deadly, error for any canine labelled a pit bull.

"In the high-stakes world of animal shelters, a dog's life might depend on a potential adopter's momentary glimpse and assumptions about its suitability as a pet. If shelter staff has labelled the dog as a pit bull, its chances for adoption automatically go down in many shelters,” says Julie Levy, professor of shelter medicine at the University of Florida College of Veterinary Medicine and the lead author of a study published in The Veterinary Journal.

"Identification of dogs as pit bulls can trigger an array of negative consequences, from the loss of housing to being seized by animal control, to the taking of the dog's life."

The findings show one in five dogs genetically identified as 'pit bulls' were missed by shelter staff while one in three deemed to be pit bulls had genetic testing which contradicted the claim.

More than half (52%) of staff identified dogs as pit bull-type when in fact DNA showed only 21% were indeed pit bull type.

The findings are troubling given shelter staff and veterinarians are often expected to guess a dog's breed based on appearance alone and potential adopters often infer, based on apparent breed, what kind of pet a particular pooch will make.

The past few decades have seen an increase in ownership restrictions on breeds including pit bulls and dogs that resemble them based on assumptions certain breeds are inherently dangerous, that such dogs can be reliably identified and restrictions will improve public safety, the study states.

That reality, in addition to negative stereotypes dogging pit bull-types, means inconsistency by shelter staff to correctly identify a breed can be dangerous - the designation often devastating, and at times a death sentence, for dogs waiting to be adopted.

"These results raise difficult questions because shelter workers and veterinarians are expected to determine breeds of dogs in their facilities on a daily basis. Additionally, they are often called on as experts as to whether a dog's breed will trigger confiscation or regulatory action. The stakes for these dogs and their owners are in many cases very high,” Levy says.

"A dog's physical appearance cannot tell observers anything about its behaviour. Even dogs of similar appearance and the same breed often have diverse behavioural traits in the same way human siblings often have very different personalities.”

Researchers evaluated breed assessments of 120 dogs made by 16 shelter workers, including four veterinarians, at four facilities – all had a minimum of three years experience working at shelters.

Then researchers developed DNA profiles from blood samples taken from each dog and compared the findings against staff assessments.

Levy suggests, rather than relying on a dog's appearance or apparent breed as a predictor of behaviour, public safety would be better served by taking steps to prevent dog bites, including supervising children, understanding canine body language, fixing dogs and socializing puppies.

By Nadia Moharib
Nadia Moharib is an animal lover who has adopted everything from birds to hamsters, salamanders, rabbits, fish and felines. She has written about all-things-pets for years and was a long-time editor of a pet magazine in a daily newspaper which featured a Q & A column, Ask Whit, penned by her pooch (ghost written, of course.) The serial dog owner lives in Calgary, Alberta and most days can be found at a dog park picking up after her rescue pooch, Scoots.

New App Identifies Dog Breed From a Photo

There’s a fun new Microsoft app called Fetch! that uses artificial intelligence techniques to classify images of real-world dogs into breeds. Available for iPhones and on the web, users upload a photo of a dog or take a picture with their camera and the app confirms the dog’s breed.

For example, if you upload a photo of a Labrador retriever, the app should say it's a Lab.

Created with a sense of humour, it includes a mode that lets you find out what breeds you and your friends are.

Fetch! was released by Microsoft Garage, an “outlet for experimental projects” and like other Microsoft artificial intelligence apps, it should become more accurate as users upload more photos and data.

A small experiment with a variety of photos came up with these mixed results:

Pretty close - poodle/golden retriever.

Sorry - Lab/boxer mix. A profile shot may not be the best for this app.

Fetch! was fooled with this goat. Maybe you can see a bit of cocker spaniel in the shape of the face?

 

The app did not get fooled twice. It recognized the cat right away.

While Fetch! may never replace a DNA test, it's a fun app for dog lovers.

RESEARCH - Dog DNA Examined for Genetic Links to Behaviour

Regular folk may watch the dog chase its tail for mere entertainment. But researchers want to explore such behaviour to see if it might be driven by something in the doggie DNA.

There are 3,000 dogs, and counting, enrolled in the project dubbed Darwin's Dogs which will compare information about canine behaviour against their DNA profiles. Darwin's dog “follows the pawprints of evolution” and tries to understand how dog DNA changed as the creatures went from living in the wild to being part of human households.

With human studies, researchers have found links between psychiatric disorders by analyzing DNA samples with success in issues including depression and schizophrenia. But because the human population is so genetically diverse, there hasn't been success in exposing a genetic link for conditions like obsessive-compulsive disorder.

With more “genetically homogenous” dogs, however, the hope is that there will be more luck on locating links. And if they can better understand how genetic changes can lead to behaviour differences — even for normal behaviours — it will ideally offer insight into psychiatric and neurological diseases in dogs as well as humans.

Purebreds are the more typical target when it comes to genetic studies in dogs, given breeding has been aimed at making them “highly genetically consistent.”
But in this study mutts will be part of the mix, says geneticist Elinor Karlsson, assistant professor at the University of Massachusetts Medical School.

Of course, most of the research regarding dogs' behaviour will be done with owners who observe it – and researchers anticipate that will be an easy task. “Fortunately, it turns out that people love to talk about their dogs,” Karlsson says.


By Nadia Moharib


Nadia Moharib is an animal lover who has adopted everything from birds to hamsters, salamanders, rabbits, fish and felines. She has written about all-things-pets for years and was a long-time editor of a pet magazine in a daily newspaper which featured a Q & A column, Ask Whit, penned by her pooch (ghost written, of course.) The serial dog owner lives in Calgary, Alberta and most days can be found at a dog park picking up after her rescue pooch, Scoots.

Is Single Injection Sterilization of Male and Female Animals in Our near Future?

There is currently a vaccine that causes the animal’s immune system to produce antibodies that block gonadotropin-releasing hormone (GnRH). This hormone is required for egg and sperm development. By blocking both egg and sperm development the vaccine is effective for male and female animals. Unfortunately, like other vaccines, the immune response will decrease over time and revaccination may be required.

Scientists at the California Institute of Technology have created an injection that causes mouse muscles to produce hormone-blocking antibodies. If the same injection works for cats and dogs then it could be used on pets and feral animals to assist population control. Current sterilization procedures are often limited to surgical procedures. The cost and invasiveness of surgery can often prevent pets and stray animals from being sterilized. In 2014, nearly 2.7 million dogs and cats were euthanized in America's shelters. An easier method of animal sterilization will help save lives.

The researchers created a piece of DNA and put it inside inactive virus shells. When injected into mice the muscles begin producing anti-GnRH antibodies. Muscle tissue is long lasting and could produce antibodies for more than ten years and would therefore not require revaccination in certain animals. This injection takes two months for efficacy to be reached. Biologist Bruce Hay said, “That 2-month delay is because of how long it takes the muscle to start producing enough antibody. Going forward, one goal is certainly to try other systems that wouldn’t have that time lag.”

Using a similar approach (injecting modified DNA) the eggs of female mice can become impenetrable by sperm. The benefit of this approach is that the hormone levels and males and females will remain the same which can be behaviourally beneficial. Hay said, “There might be some instances in wild animals where you just want to inhibit fertility but not disrupt an animal’s behavior.” Researcher, Dr. Robert McCarthy performed a study that suggested that feral cat population control is likely to be much more effective if reproductive hormones remain intact.

Cincinnati Zoo and Botanical Garden Director of Animal Research, William Swanson said, “This looks incredibly promising. We’re all very excited about this approach; that it’s going to be the one that really works.” Swanson will be testing the DNA injection approach in cats. Swanson said, “The challenge is always moving between species.” If the injection works it could change the way we control feral cat populations. “We have to figure out how to control these populations without being harmful to individual cats. And this kind of lifelong contraception might be a safe, effective way to do that,” said Swanson.

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