Dog Facts: The Amazing Powers of Working Dogs
Humans and Working Dogs
Dogs and humans have worked together for thousands of years. Working dogs have played a vital role in hunting, herding, rescue, security and law-enforcement. The sheer strength and resilience of working dog breeds is marvelous.
Working Dogs and Breed Adaptations
There are dogs as big as bears, and dogs small enough to fit in a ladies' handbag. Dogs can be short-haired, long-haired, slender, stocky, bred for speed, intelligence, or docility. But despite the variety in height, weight, looks, and behavior of the different breeds, all dogs have powerful muscles for their size, and anatomical adaptations which make them capable of extraordinary feats of endurance and strength.
The Variety of Working Dog Breeds
Selective breeding over millennia has led to the plethora of breeds, each endowed with particular powers. The huge, long-haired Newfoundland, for example, is a powerful long-distance swimmer and can drive through snow like a plow. It's one of the largest breeds and has strong lungs and a heavy skeleton bred for endurance. The beautiful Alaskan Husky can pull a sled over three times its weight.
15,000 Years of "Man's Best Friend"
Dogs and humans have worked together to their mutual benefit for almost 15,000 years. Many prehistorians believe the original inhabitants of North American arrived from Siberia by crossing the Bering Strait on sleds pulled by working dogs. But what are the qualities and adaptations that give dogs these amazing powers of strength and endurance?
Ancient Working Dogs and Humans Documentary
A Wolfish Bite
All modern dog breeds descend from their wild cousins, the wolves. Dogs, like wolves, are natural predators. They have strong jaws evolved to grab, pull, and tear prey animals. A dog's bite-strength is vastly superior to a human's. This extraordinary bite means dogs excel as hunting companions, guard dogs, and rescue dogs.
The Advantages of Canine Anatomy and Physiology
Wild wolves spend many days travelling through mountains and forests in search of food. Domestic dogs have retained traits which enable them to sustain running and walking over long periods of time. Canine anatomy and physiology account for a dog's remarkable stamina. A long body on four legs enables it to keep a steady rate of movement without exhausting its reserves of energy. A dog can also regulate core temperature during exercise by panting and raising or lowering fur.
Working Dogs and Thermoregulation
Dogs can survive under a range of extreme environmental conditions, from the icy wastes of the Arctic to the hot, humid tropics. A dog's cardiovascular system has evolved to regulate its brain temperature and respond rapidly to environmental changes. In cold conditions, warm blood circulates around the brain, keeping the dog alert and its nervous system functioning well. In hot conditions, blood carries heat away from the brain so it doesn't overheat.
A History of Working Dogs
The Metabolism of Working Dogs
Another reason for the dog's remarkable powers of endurance is its unique ability to metabolize fats with carbohydrates as a source of energy. Anyone who has tried to lose weight through exercise alone knows how tough it is for humans to break down excess fat reserves. Because dogs can use fat as easily as carbohydrates they can switch between energy sources without difficulty. This means they have double the relative energy resources of a human. Any dog owner who has tried to tire a dog out will understand the truth of that.
Humans and Dogs: An Enduring Collaboration
Human intelligence, coupled with the dog's loyalty, strength, and resilience has led to a potent, beneficial relationship between the species. But it would be a mistake to take "man's best friend" for granted, or assume humans are superior. Dogs have extraordinary powers at which humans can only marvel.
© 2018 Amanda Littlejohn