The incredible explosion of dog breeds
From the tea cup size Chihuahua to the Great Dane, the variety of dogs is amazing. But all varieties belong to one species, so scientists studied these varieties to better understand the operation process of evolution and how such a huge variation is generated in a population.
Dogs (canine lupus) are more variable in size, shape and behavior than any other living mammal, but now most experts believe that all dogs, no matter how different, originate from only one species: the Central Asian gray wolf (canine lupus). James Seppell said that “domestic dogs: their evolution, behavior and interaction with people” (Cambridge University Press, 1995).
It is also possible that there is only one domestication event. Today, all domesticated dogs are descendants of their ancestors, and they became someone’s best friend long ago. This evidence comes from a study in 2009, in which a group of researchers from the Royal Institute of Technology in Stockholm analyzed mitochondrial DNA samples (DNA found in mitochondria, or energy production structures in cells) from dogs around the world.
They found that all dogs belonged to the same lineage, which indicated that domestication had only occurred once. (If wolves are domesticated several times in different regions, the team hopes to find more than one lineage in modern dogs.)
Although dogs were domesticated as early as 14000 to 17000 years ago, most dog breeds have been developed in the past few centuries. When people in ancient times raised dogs for loud bark (to protect the owner’s property) or docile temperament (so it is unlikely to attack the owner), they were actually repairing the dog’s genetic selection.
One of the earliest breeds believed to be purposefully selected for its preferred traits is still around today – the greyhound. Perhaps the first fully distinct breed was the Saluki, also called the Arabian greyhound, whose name translates to “noble,” according to “Simon & Schuster’s Guide to Dogs” (Fireside, 1980).
“Leslie Irving of the University of Colorado at Boulder said that he is the author of” If You Tame Me: Understanding Our Connection with Animals “(Temple University Press, 2004).
According to the Dog Guide, due to natural mutations, climate and human preferences, “breeds become more and more numerous and specialized until they reach the level of modern classification.” This classification is based on the ability of a breed in five skills: hunting, herding, guarding, working and accompanying.
At present, about 340 dog breeds have been recognized by the International Federation of Dog Breeds (FCI), which is the management organization of dog breeds in the world, sometimes called the World Dog Breeds Organization. However, different countries have different standards for breed recognition – the American Kennel Club currently only recognizes 167 breeds.
Recently, the number of “designer dogs” deliberately hybridized has been increasing. These include Labradors (a cross between Labradors and Poodles), cockatoos (a cross between cocktails and Poodles) and pugs (offspring of pugs and beagles).”
Dogs are constantly evolving as we’re continually building variants of dog breeds,” said Stanley Coren, author of “The Modern Dog” (Free Press, 2008).
“The nature of humans is to want unique things, but a unique thing is not necessarily a better thing,” Coren told Life’s Little Mysteries.
