Family overview
The family Canidae includes around fifteen genus and is well-distributed throughout much of the world. As a rule they can be characterized as "opportunistic carnivores," consuming meat when it is available but also feeding on plant matter and carrion. They are placental mammals who give birth to a litter of live young. The family may be further subdivided into two groups, "true dogs" and "foxes."
Some species, particularly the wolf (C. lupus), and by logical extension the domesticated wolves that are domesticated dogs, are noted for their comparatively complex social structures. This has given rise to a view of the canine as inherently social, although many genera within the family are at least primarily solitary. As such, Canidae may be an appealing character choice both to those who identify with the perceived independence of the red fox, or to those who see themselves reflected in the perceived loyalty and kinship of the dog.
 Canines and human beings
The relationship between humans (Homo sapiens) and canines takes a number of different forms. The domestic dog (C. lupus familiaris) was the first animal truly domesticated by humans, taking place perhaps greater than 15,000 years ago. The relationship between the two species of mammal has been proverbially close, with the dog acquiring the title of "Man's Best Friend" and accompanying him to the corners of the Earth -- domesticated or semi-domesticated dogs are found historically from North America to Australia.
However, other such ties can be strained: following the domestication of livestock, the wolf (C. lupus), on a global scale, has been driven from much of its original habitat, and has become an endangered species in many parts of the world. Considered a hazard to sheep and cattle (in some cases rightfully so) the wolf is a proverbially unwelcome sight to ranchers and farmers, and is often treated as such by hunting, trapping, and poaching.
Similarly, the red fox (C. vulpes, also classified as Vulpes vulpes), coyote (C. latrans), and dingo (C. lupus dingo) are hunted as vermin in some parts of the world -- most notably, fox hunting has become, in Éire (Ireland) and the United Kingdom, something of an instution, althought it obstentiably began as a form of pest control. However, in Sept 15th, 2004, a bill was passed in United Kingdom prohibitting fox hunting from Feb 2005.
Notably, while they are non-domesticated, the raising of some canids -- particularly, again, the fox -- for their pelts and fur remains a relatively common commercial activity in some parts of the world.
 Canines and the furry fandom
Perhaps because of the unique relationship between canines and people alluded to above, the family is well represented in the furry fandom. A search on personals website Pounced.org reveals well over half of those providing an alternate identity call themselves canine: 1577/2580 (61%), as opposed to felines (the next largest contender, with 929, or 36%). Of those identifying as canine, just over a third list their species as being "fox"; 42% list "wolf."