understanding what we are part five (continued)

Breeding and life cycle
A wolf pup looks up to others in the pack for protection.Normally, only the alpha pair of the pack breeds, which is a kind of organization not uncommon to other pack-hunting canids including the Dhole and the African Hunting Dog. Mating occurs between January and April, happening later in the year as latitude increases.[16] A pack usually produces a single litter, though sometimes multiple litters will be born if the alpha male mates with one or more subordinate females. Under normal circumstances, the alpha female will try to prevent this by aggressively dominating other females and physically separating them from the alpha male during the mating season.
A wolf resting at the entrance to its den; also note how its coloration blends in with the environment.The gestation period lasts 60–63 days, and at the weight of 0.5 kg (1 lb), the pups are born blind, deaf, and completely dependent on their mother.[16][3] There are 1–14 pups per litter, with the average litter size being about 4–6.[20] Pups reside in the den, where they are born, and stay there until they reach about 3 weeks of age.[11] The den is usually on high ground near an open water source, and has an open "room" at the end of an underground or hillside tunnel that can be up to a few meters long.[10] During this time, the pups will become more independent, and will eventually begin to explore the area immediately outside the den before gradually roaming up to a mile away from it at around 5 weeks of age.[11] They begin eating regurgitated foods after 2 weeks— by which time their milk teeth have emerged— and are fully weaned by 8–10 weeks.[11] During the first weeks of development, the mother usually stays with her litter alone, but eventually most members of the pack will contribute to the rearing of the pups in some way.[16]
After 2 months, the restless pups will be moved to a rendezvous site, which gives them a safe place to reside while most of the adults go out to hunt.[11] An adult or two will stay behind to ensure the safety of the pups. After a few more weeks, the pups are permitted to join the adults if they are able (they tag along as observers until about 8 months, by which time they are large enough to actively participate),[11] and will receive first priority on anything killed, their low ranks notwithstanding. Letting the pups fight for eating privileges results in a secondary ranking being formed among them, and allows them to practice the dominance/submission rituals that will be essential to their future survival in pack life.[16]
Wolves typically reach sexual maturity after 2 or 3 years, at which point many of them will feel compelled to leave their birth packs and search out mates and territories of their own.[16][21] Wolves that reach maturity generally live 6–8 years in the wild, although in captivity they can live to be twice that age.[20] High mortality rates result in a relatively low life expectancy for wolves on an overall basis. Pups die when food is scarce; they can also fall prey to other predators such as bears, or, less likely, coyotes, foxes, or other wolves. The most significant mortality factors for grown wolves are hunting and poaching by humans, car accidents, and wounds suffered while hunting prey. Wolves are susceptible to the same infections that affect domestic dogs, such as mange, heartworm, rabies and canine distemper, and such diseases can become epidemic, drastically reducing the wolf population in an area.

Behavior
Body language
See also: Dog communication
This facial expression is defensive and gives warning to other wolves to be cautious.
This facial expression shows fear.
This wolf's submissive posture, wagging tail and horizontal ears show a friendly greeting.Wolves can visually communicate an impressive variety of expressions and moods that range from subtler signals, such as a slight shift in weight, to the more obvious ones, like rolling on the back as a sign of complete submission.[22]

Dominance – A dominant wolf stands stiff legged and tall. The ears are erect and forward, and the hackles bristle slightly. Often the tail is held vertical and curled toward the back. This display shows the wolf's rank to all others in the pack. A dominant lupine may stare penetratingly at a submissive one, pin it to the ground, "ride up" on its shoulders, or even stand on its hind legs.
Submission (active) – In active submission, the entire body is lowered, and the lips and ears are drawn back. Sometimes active submission is accompanied by muzzle licking, or the rapid thrusting out of the tongue and lowering of the hindquarters. The tail is placed down, or halfway or fully between the legs, and the muzzle often points up to the more dominant animal. The back may be partially arched as the submissive wolf humbles itself to its superior; a more arched back and more tucked tail indicate a greater level of submission.
Submission (passive) – Passive submission is more intense than active submission. The wolf rolls on its back and exposes its vulnerable throat and underside. The paws are drawn into the body. This is often accompanied by whimpering.
Anger – An angry lupine's ears are erect, and its fur bristles. The lips may curl up or pull back, and the incisors are displayed. The wolf may also arch its back, lash out, or snarl.
Fear – A frightened wolf tries to make its body look small and therefore less conspicuous. The ears flatten down against the head, and the tail may be tucked between the legs, as with a submissive wolf. There may also be whimpering or barks of fear, and the wolf may arch its back.
Defensive – A defensive wolf flattens its ears against its head.
Aggression – An aggressive wolf snarls and its fur bristles. The wolf may crouch, ready to attack if necessary.
Suspicion – Pulling back of the ears shows a lupine is suspicious. In addition, the wolf narrows its eyes. The tail of a wolf that senses danger points straight out, parallel to the ground.
Relaxedness – A relaxed wolf's tail points straight down, and the wolf may rest sphinx-like or on its side. The wolf may also wag its tail. The further down the tail droops, the more relaxed the wolf is.
Tension – An aroused wolf's tail points straight out, and the wolf may crouch as if ready to spring.
Happiness – As dogs do, a lupine may wag its tail if it is in a joyful mood. The tongue may loll out of the mouth.
Hunting – A wolf that is hunting is tensed, and therefore the tail is horizontal and straight.
Playfulness – A playful lupine holds its tail high and wags it. The wolf may frolic and dance around, or bow by placing the front of its body down to the ground, while holding the rear high, sometimes wagged. This is reminiscent of the playful behavior demonstrated by domestic dogs.

Howling
Wolves howl for several reasons. Howling helps pack members keep in touch, allowing them to effectively communicate in thickly forested areas or over great distances. Furthermore, howling helps to summon pack members to a specific location. Howling can also serve as a declaration of territory, as portrayed by a dominant wolf's tendency to respond to a human imitation of a "rival" individual in an area that the wolf considers its own. This behavior is also stimulated when a pack has something to protect, such as a fresh kill. As a rule of thumb, large packs will more readily draw attention to themselves than will smaller packs. Adjacent packs may respond to each others' howls, which can mean trouble for the smaller of the two. Thus, wolves tend to howl with great care.[23]

Howling
adult wolf on glacial erratic at Little America Flats.Wolves will also howl for communal reasons. Some scientists speculate that such group sessions strengthen the wolves' social bonds and camaraderie— similar to community singing among humans.[23] During such choral sessions, wolves will howl at different tones and varying pitches, which tends to prevent a listener from accurately estimating the number of wolves involved. This concealment of numbers makes a listening rival pack wary of what action to take. For example, confrontation could mean bad news if the rival pack gravely underestimates the howling pack's numbers.
Observations of wolf packs suggest that howling occurs most often during the twilight hours, preceding the adults' departure to the hunt and following their return. Studies also show that wolves howl more frequently during the breeding season and subsequent rearing process. The pups themselves begin howling soon after emerging from their dens and can be provoked into howling sessions relatively easily over the following two months. Such indiscriminate howling usually has a communicative intent, and has no adverse consequences so early in a wolf's life.[23] Howling becomes less indiscriminate as wolves learn to distinguish howling pack members from rival wolves.

The pack
Wolves function as social predators and hunt in packs organized according to strict, rank-oriented social hierarchies.[16] It was originally thought that this comparatively high level of social organization had more to do with hunting success, and while this still may be true to a certain extent, emerging theories suggest that the pack has less to do with hunting and more to do with reproductive success.
The pack is led by the two individuals that sit atop the social hierarchy: the alpha male and the alpha female. The alpha pair (of whom only one may be the "top" alpha) has the greatest amount of social freedom compared to the rest of the pack, but they are not "leaders" in the human sense of the term. The alphas do not give the other wolves orders; rather, they simply have the most freedom in choosing where to go, what to do, and when to do it. Possessing strong instincts for fellowship, the rest of the pack usually follows.
While most alpha pairs are monogamous with each other, there are exceptions.[26] An alpha animal may preferentially mate with a lower-ranking animal, especially if the other alpha is closely related (a brother or sister, for example). The death of one alpha does not affect the status of the other alpha, who will quickly take another mate.[16]
Usually, only the alpha pair is able to successfully rear a litter of pups. Other wolves in a pack may breed, but will usually lack the resources required to raise the pups to maturity. All the wolves in the pack assist in raising wolf pups. Some mature individuals, usually females, may choose to stay in the original pack so as to reinforce it and help rear more pups. However, most will disperse, males particularly.
The size of the pack may change over time and is controlled by several factors, including habitat, personalities of individual wolves within a pack, and food supply. Packs can contain 2–20 wolves, though an average pack consists of 6 or 7.[27][28] New packs are formed when a wolf leaves its birth pack and claims a territory. Lone wolves searching for other individuals can travel very long distances seeking out suitable territories. Dispersing individuals must avoid the territories of other wolves because intruders on occupied territories are chased away or killed, a behavior that may explain wolf "predation" of dogs. Most dogs, except perhaps large, specially bred attack dogs, do not stand much of a chance against a pack of wolves protecting its territory from an unwanted intrusion.