September 2015
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Pet Circkles.

"I am in favor of animal rights as well as
human rights. That is the way of a
whole human being." ~ Abe Lincol

How Pets Evolved and How it Affects Their evolution chart

The Evolution of the Dog.


From a Chihuahua to a St. Bernard, dogs come in such variety, sizes and shapes, it's easy to forget they belong to the same species. Today there are some 150 different dog breeds created by the intense interbreeding of dogs in the past 150 years.

One consequence of interbreeding to create purebreds with sharply individual traits is that many disease-causing genes have become concentrated in these breeds. Because of the growing concern about health problems and the availability of powerful methods to hunt genes, scientists are hard at work on the "dog genome project." As with the Human Genome Project, the goal is to locate and map canine genes, particularly those that play a role in disease. Genes that influence behavior are also of great interest.

At the same time, the entire history of dogs and their relationship with humans has undergone some rethinking recently, thanks in large part to high-tech molecular dating methods that can determine evolutionary relationships and chronologies.

dogs descended from wolvesThe dog, Canis familiaris, is a direct descendent of the gray wolf, Canis lupus, domesticated about 130,000 years ago. In other words, dogs as we know them are domesticated wolves. Not only their behavior changed; domestic dogs are different in form from wolves, mainly smaller and with shorter muzzles and smaller teeth. But if they all share a common ancestor, why do toy poodles and Great Danes seem to have little in common? Years of selective breeding by humans has resulted in the artificial "evolution" of dogs into many different types.

Darwin was wrong about dogs. He thought their remarkable diversity must reflect interbreeding with several types of wild dogs. But the DNA findings say differently. All modern dogs are descendants of wolves, though this domestication may have happened twice, producing groups of dogs descended from two unique common ancestors.

How and when this domestication happened has been a matter of speculation. It was thought until very recently that dogs were wild until about 12,000 years ago. But DNA analysis published in 1997 suggests a date of about 130,000 years ago for the transformation of wolves to dogs. This means that wolves began to adapt to human society long before humans settled down and began practicing agriculture.

This earlier timing casts doubt on the long-held myth that humans domesticated dogs to serve as guards or companions to assist them. Rather, say some experts, dogs may have exploited a niche they discovered in early human society and got humans to take them in out of the cold.

cat evolutionary chainThe Evolution of the Cat.

The evolution of the domestic house cat is not as straightforward as you might expect. Twenty-first century science has illuminated some aspects of domestication, but lineages remain murky. In short, all cats probably evolved from the prehistoric proailurus, which was either the last cat precursor or the first cat. Cats traveled from Eurasia to North America and back again multiple times through the course of prehistory, spreading throughout the world by millions of years ago according to 21st century scientific studies.

The domestication of the house cat came much more recently. Scientists used to think the Egyptians were the first people to domesticate cats, roughly 3,600 years ago; but new evidence puts domestic cats in the Fertile Crescent perhaps as long as 10,000 years ago.
Warren E. Johnson and Stephen J. O'Brien, both of the National Cancer Institute, and other scientists have used DNA evidence to chart lineages of all cats, big and small. They've identified 37 species, all of which evolved from pseudaelurus and, by extension, proailurus, who lived on our planet between 20 and 30 million years ago.

Pseudaelurus was a prehistoric cat that lived in Eurasia and North America roughly 20 million years ago. The pseudaelurus had slender proportions and short legs, not unlike a weasel. It died out about 8 million years ago. In scientific literature it's sometimes cited as the basal stock of the Felidae family. Its predecessor was the proailurus, which lived in caracalEurasia roughly 25 million years ago.
The proailurus was slightly bigger than a domestic cat. It had a long tail and probably hung out in trees. Some scientists posit it as the basal stock of the Feliformia superfamily -- this includes Felidae and similar animals -- but other scientists dub it the first true felid.

All cats -- that is, all felids -- share common traits. This might seem counter-intuitive if you're comparing your house cat with a tiger. Remember, though, the term "big cats" carries no biological significance apart from size distinction. It may help to keep in mind that the similarities found in ancient cat remains have made tracing their genealogy quite difficult.
In any case, all cats are obligate carnivores (they have to eat meat), many are social, and they're often nocturnal. No members of the Felidae family have taste receptors for sweetness.

Why is Knowing any of This Important?

As many pet owners have learned the hard way, too much specialty breeding is detrimental to the health of an animal The best example is the Shar-Pei breed which was discovered by a breeding accident. When the cute, wrinkled faces were discovered, the Shar Pei was then inbred extensively to try and replicate those features which made them so cute and desirable to the pet market. Unfortunately for the Shar peis though, all that inbreeding causes numerous health problems and now the breed is labeled as one of the worst to have due to the high expense of medical problems they have developed and the emotional cost when these lovable dogs die at a very young age.

sharp pei pupOnly after the Shar Pei tragedy did pet owners become aware of the many, many years pet breeders have been playing God with the dog species and ruining it's chances for survival with their superficial and greedy desire to keep breeding dogs for looks and show rather than health. Pet owners now know the value of a dog breed is in how healthy it is not how it looks. However, as long as there is a market or a trend for a certain breed, unethical breeders and the pet industry will find some way to capitalize on it whether it is in the best interest of the animal or the pet owner. Once again, pet owners need to educate themselves on a breed before buying it.

This is why we at Circkles have a monthly column on the different breeds and the health concerns associated with each. If you follow our Pet Circkles Club, you can use these reference articles to do your research before you buy.


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About Pet Circkles:

Allen M. Shoen, a veterinarian and author of "Kindred Spirit" wrote, "Although science has no definite answers, why not assume that sharing a home with a dog, cat or bird - or sharing our lives with a horse or other large animal - has therapeutic benefits that are deeper than simple stimulation of the opiate receptors in the skin through touch? Perhaps, through our connection with animals, we are stimulating some deeply buried aspect of nature within us, rekindling a lost connection that allows us to be more than solitary creatures, but part of something greater - and therefor, more healthy, more whole."

Much scientific and psychological research has proven just that. And also that the human animal bond is mutually beneficial under humane circumstances. Many great philosophers, such as Albert Einstein, recognized that we have a great deal of useful information to learn from animals.
In fact, animals are the great teachers, not us, for they have roamed the earth far longer than we and express genuine thought and expression true to their nature, which we do not. We have a great deal to learn from them. Pet Circkles helps us stay more in touch with their health, diet and social needs so we can give back to those who give us so much unconditionally.


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chinook dog breed

Featured DOG BREED: Chinook

This extremely hard working breed nearly became extinct and today it is estimated that there are only 500 in existence. The breed is considered to be rare and is difficult to obtain.

Although still used for recreational dog sledding by some owners, the Chinook is a rare breed of sled dog, developed in the state of New Hampshire during the early 20th century. Chinooks today appear to be used largely as family pets. Individuals are also used for dog-packing, search and rescue, skijoring, and obedience and dog agility trials.

This dog breed is loyal, clever, calm and friendly. The Chinook is excellent with children, other dogs and non-canine pets. This dog breed is somewhat cautious of unfamiliar surroundings and strangers, but is never aggressive or timid. The breed is reliable, versatile, devoted and tolerant. This dog breed is an excellent worker and family companion. The breed is not recommended for watchdog purposes as they are not prone to bark. This breed is sensitive and do not like to be left alone for extended periods.

The medium-length double coat is "tawny" in color, with darker shadings on muzzle and ears

An affectionate and playful family companion with a special devotion toward children. It is a willing worker who is eager to please and enthusiastic to learn. The Chinook is highly trainable, adaptable, and versatile in his abilities. Gregarious with other dogs, the Chinook works well in teams and within family packs. The Chinook is a dignified dog; some may be reserved with strangers but should never appear shy or aggressive.

Health Concerns: Health issues include normal hereditary problems such as epilepsy, hip dysplasia, and atopy. Also common is cryptorchidism, which occurs in about 10% of all male dogs.

Size: Standing 21 to 27 inches (53 to 69 cm) in height at the withers and weighing 55 to 90 pounds (25 to 41 kg), the Chinook is balanced and muscular.

Looking for a Chinook? Use our Pet finder tool below and search for an adoptable dog that needs a home in your area now.

To view breeds we've already written about, go to our Pet Circkles Club Page.

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