Wolves as pets and working animals
Though wolves are trainable, they lack the same degree of tractability seen in dogs. They are generally not as responsive as dogs to coercive techniques involving fear, aversion to stimuli, and force. Generally, far more work is required to obtain the same degree of reliability seen in most dogs. Even then, once a certain behavior has been repeated several times, wolves may get bored and ignore subsequent commands. Wolves are most responsive toward positive conditioning and rewards, though simple praise is not sufficient as in most dogs. Unlike dogs, wolves tend to respond more to hand signals than voice. Although they are more difficult to control than dogs, they can be easier to teach if the motivation exists.
Wolves are less suitable than dogs for working. Swedish wolf biologist Erik Zimen once tried to form a dog sled team composed entirely of wolves. The experiment failed as the wolves ignored most commands and were far more prone to fighting than sled dogs. North American wolves and wolf hybrids were used as experimental attack dogs by the South African Defence Force in Apartheid South Africa in an attempt to breed animals capable of tracking guerrillas. Because the wolves would not follow even basic commands, the experiment was abandoned. However, their sense of smell can rival that of established scent hounds. According to reports published in 2006, ongoing research at the Perm Institute of Internal Troops in Russia demonstrated that wolf/dog cross-breeds took 15–20 seconds to track down a target in training sessions, whereas ordinary police dogs took 3–4 minutes. Their success has led to plans to use them as police dogs for the Russian police.
Wolfdog
The physical characteristics of an animal created by breeding a wolf to a dog are not predictable, similar to that of mixed-breed dogs. Genetic research shows that wolf and dog populations initially diverged approximately 14,000 years ago and have interbred only occasionally since, accounting for the dissimilarity between dogs and wolves in behavior and appearance. In many cases the resulting adult wolfdog may be larger than either of its parents due to the genetic phenomenon of heterosis (commonly known as "hybrid vigor"). Breeding experiments in Germany with Poodles and wolves, and later on with the resulting wolfdogs showed unrestricted fertility, mating via free choice and no significant problems of communication (even after a few generations). The offspring of poodles with either coyotes and jackals however all showed a decrease in fertility, significant communication problems, and an increase of genetic diseases after three generations of interbreeding between the hybrids. The researchers therefore concluded that domestic dogs and wolves are the same species.