About Dogs

Tuesday, August 28, 2007

Scientific Name Canis lapus familiaris or Dogs, a domestic mammal subspecies of the wolf, one of the most widely-kept working and companion animal to human, the man’s best friend. The first animal on our planet who enter space and fly into Earth’s orbit. The word Dog in common usage refers to the domesticv pet dog, a reclassified as a subspecies of the gray wolf, Canis lupus. "Dog" is sometimes used to refer collectively to any mammal belonging to the dog family Canidae such as wolves, foxes, and coyotes.

The English word dog might derive from the Old English docga meaning "powerful breed of canine", while the word hound is a cognate of German Hund, Dutch hond, common Scandinavian hund, Icelandic hundur which, though referring to a specific breed in English, means "dog" in general in the other Germanic languages.

In breeding circles, a male canine is referred to as a dog, while a female canine is called a bitch. The father of a litter is called the sire, and the mother of a litter is called the dam. Offspring are generally called pups or puppies until they are about a year old. A group of offspring is a litter. The process of birth is whelping.

Dogs are very social animals, but their personality and behavior vary with breed as well as how they are treated by their owners and others who come in contact with them. It is not uncommon for dogs to attack humans and other animals; however, this is usually because of lack of care or improper upbringing by its owner.

• Livestock guardian dogs exhibit the controlled characteristics of hunting dogs. Members of this group, such as Border Collies, Belgian Malinois, and German Shepherds use tactics of hunter and prey to intimidate and keep control of herds and flocks. Their natural instinct to bring down an animal under their charge is muted by training. Other members of the group, including Welsh Corgis, Canna dogs, and Cattle dogs herd with a more aggressive demeanor and make use of body design to elude the defences of their charges.
• Gun dog breeds used in hunting—that is, pointers, setters, spaniels, as retrievers —have an intermediate degree of paedomorphism; they are at the point where they share in the pack's hunting behavior, but are still in a junior role, not participating in the actual attack. They identify potential prey and freeze into immobility, for instance, but refrain from then stalking the prey as an adult predator would do next; this results in the "pointing" behavior for which such dogs are bred. Similarly, they seize dead or wounded prey and bring it back to the "pack", even though they did not attack it themselves, that is, "retrieving" behavior. Their physical characteristics are closer to that of the mature wild canine than the sheepdog breeds, but they typically do not have erect ears, etc.

• Scenthounds maintain an intermediate body type and behavior pattern that causes them to actually pursue prey by tracking their scent, but tend to refrain from actual individual attacks in favor of vocally summoning the pack leaders (in this case, humans) to do the job. They often have a characteristic vocalization called a bay. Some examples are the Beagle, Bloodhound, Basset Hound, Coonhound, Dachshund, Fox Hound, Otter Hound, and Harrier.
• Sighthounds, who pursue and attack perceived prey on sight, maintain the mature canine size and some features, such as narrow chest and lean bodies, but have largely lost the erect ears of the wolf and thick double layered coats. Some examples are the Afghan, Borzoi, Saluki, Sloughi, Pharaoh Hound, Azawakh, Whippet, and Greyhound.
• Mastiff-types are large dogs, both tall and massive with barrel-like chests, large bones, and thick skulls. They have traditionally been bred for war, protection, and guardian work.
• Bulldog-types are medium sized dogs bred for combat against both wild and domesticated animals. These dogs have a massive, square skull and large bones with an extremely muscular build and broad shoulders.
• Terriers similarly have adult aggressive behavior, famously coupled with a lack of juvenile submission, and display correspondingly adult physical features such as erect ears, although many breeds have also been selected for size and sometimes dwarfed legs to enable them to pursue prey in their burrows.

Dogs are valued for their intelligence. This intelligence is expressed differently with different breeds and individuals, however. Being highly adaptable animals themselves, dogs have learned to do many jobs as required by humans over the generations. Dogs are employed in various roles across the globe, proving invaluable assets in areas such as search-and-rescue; law enforcement (including attack dogs, sniffer dogs and tracking dogs); guards for livestock, people or property; herding; Arctic exploration sled-pullers; guiding the blind and acting as a pair of ears for the deaf; assisting with hunting, and a great many other roles which they may be trained to assume. Most dogs rarely have to deal with complex tasks and are unlikely to learn relatively complicated unaided. Some dogs are specially trained to recognize and avoid dangerous situations.

Dog’s Sight - like most mammals, dogs are dichromats and have color vision equivalent to red-green color blindness in humans. Different breeds of dogs have different eye shapes and dimensions, and they also have different retina configurations. Dogs with long noses have a "visual streak" which runs across the width of the retina and gives them a very wide field of excellent vision, while those with short noses have an "area centralis" — a central patch with up to three times the density of nerve endings as the visual streak — giving them detailed sight much more like a human's.

Dog’s Hearing - Dogs detect sounds as low as the 16 to 20 Hz frequency range (compared to 20 to 70 Hz for humans) and above 45 kHz (compared to 13 to 20 kHz for humans), and in addition have a degree of ear mobility that helps them to rapidly pinpoint the exact location of a sound. Eighteen or more muscles can tilt, rotate and raise or lower a dog's ear. Additionally, a dog can identify a sound's location much faster than a human can, as well as hear sounds up to four times the distance that humans are able to. Those with more natural ear shapes, like those of wild canids like the fox, generally hear better than those with the floppier ears of many domesticated species.

Dog’s Smelling - Dogs have nearly 220 million smell-sensitive cells over an area about the size of a pocket handkerchief. Some breeds have been selectively bred for excellence in detecting scents, even compared to their canine brethren. What information a dog actually detects when he is scenting is not perfectly understood; although once a matter of debate, it now seems to be well established that dogs can distinguish two different types of scents when trailing, an air scent from some person or thing that has recently passed by, as well as a ground scent that remains detectable for a much longer period.