The domestic dog is a subspecies of the gray wolf, a member of the Canidae family of the mammalian order Carnivora. The term "domestic dog" is generally used for both domesticated and feral varieties.


Dog Characteristics

Dogs are capable of learning in a number of ways, such as through simple reinforcement and by observation. Domestic dogs have been selectively bred for millennia for various behaviours, sensory capabilities, and physical attributes. They have a predisposition to exhibit a social intelligence that is uncommon in the animal world.

Modern dog breeds show more variation in size, appearance, and behaviour than any other domestic animal. They hugely draw from their wild ancestors and gray wolves. Dogs are predators and scavengers, and like many other predatory mammals, the dog has powerful muscles, fused wrist bones, a cardiovascular system that supports both sprinting and endurance, and teeth for catching and tearing.

Dogs are highly variable in height and weight. The smallest known adult dog was a Yorkshire Terrier that stood only 6.3 cm (2.5 in) at the shoulder, 9.5 cm (3.7 in) in length along the head-and-body, and weighed only 113 grams (4.0 oz). The largest known dog was an English Mastiff which weighed 155.6 kg (343 lb.) and was 250 cm (98 in) from the snout to the tail. The tallest dog is a Great Dane that stands 106.7 cm (42.0 in) at the shoulder.


Fact File

  • Scientific name: Canis lupus familiaris
  • Lifespan: 11.083 years on average
  • Gestation period: 58 – 68 days
  • Daily sleep: 10.1 hours on average
  • Height: 6.3 – 106.7 cm (At Shoulder)
  • Rank: Subspecies



The frequency range of dog hearing is approximately 40 Hz to 60,000 Hz, which means that dogs can detect sounds far beyond the upper limit of the human auditory spectrum. In addition, dogs have ear mobility, which allows them to rapidly pinpoint the exact location of a sound. Eighteen or more muscles can tilt, rotate, raise, or lower a dog's ear. A dog can identify a sound's location much faster than humans can, as well as hear sounds at four times the distance.



It has been estimated that dogs, in general, have an olfactory sense ranging from one hundred thousand to one million times more sensitive than a human's. In some dog breeds, such as bloodhounds, the olfactory sense may be up to 100 million times greater than humans. The wet nose or rhinarium is essential for determining the direction of the air current containing the smell.




Dogs go through a series of stages of cognitive development. Puppies learn behaviors quickly by following examples set by experienced dogs.

This form of intelligence is not peculiar to those tasks dogs have been bred to perform, but can be generalized to myriad abstract problems. Dogs can also learn by mimicking human behaviours.