Wolves function as social predators and hunt in packs organized according to strict, rank-oriented social hierarchies.

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. 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.

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.
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.

A wolf pack in Yellowstone National Park, with the alphas leading and the omega in the rear.

The hierarchy, led by the alpha male and female, affects all activity in the pack to some extent. In most larger packs, there are two separate hierarchies in addition to an overbearing one: the first consists of the males, led by the alpha male, and the other consists of the females, led by the alpha female.In this situation, the alpha male was assumed to be the "top" alpha at the position, but biologists have concluded that alpha females can and do take control over entire packs. The male and female hierarchies are interdependent, and are maintained constantly by aggressive and elaborate displays of dominance and submission.

After the alpha pair, there may also, especially in larger packs, be a beta wolf or wolves, a "second-in-command" to the alphas. Betas typically assume a more prominent role in assisting with the upbringing of the alpha pair's litter, often serving as surrogate mothers or fathers while the alpha pair is away. Beta wolves are the most likely to challenge their superiors for the role of the alpha, though some betas seem content with being second, and will sometimes even let lower ranking wolves leapfrog them for the position of alpha should circumstances necessitate such a happening, such as the death of the alpha. More ambitious beta wolves, however, will only wait so long before challenging for the top spot unless they choose to disperse and create their own pack instead

Loss of rank can happen gradually or suddenly. An older wolf may simply choose to give way when a motivated challenger presents itself, yielding its position without bloodshed. On the other hand, the challenged individual may choose to fight back, with varying degrees of intensity. While the majority of wolf aggression is non-damaging and ritualized, a high-stakes fight can easily result in injury for either or both parties. The loser of such a confrontation is frequently chased away from the pack or, rarely, may be killed as other aggressive wolves contribute to the insurgency. This kind of dominance encounter is more common during the mating season.

Rank order within a pack is established and maintained through a series of ritualized fights and posturing best described as "ritual bluffing". Wolves prefer psychological warfare to physical confrontations, meaning that high-ranking status is based more on personality or attitude than on size or physical strength. Rank, who holds it, and how it is enforced varies widely between packs and between individual animals. In large packs full of easygoing wolves, or in a group of juvenile wolves, rank order may shift almost constantly, or even be circular (e.g., animal A dominates animal B, who dominates animal C, who dominates animal A).

In a more typical pack, however, only one wolf will assume the role of the omega: the lowest-ranking member of a pack.
These individuals absorb the greatest amount of aggression from the rest of the pack, and may be subjected to different forms of truculence at any given point— anything from constant dominance from other pack members to inimical, physical harassment. Although this arrangement may seem objectionable after cursory analysis, the nature of pack dynamics demands that one wolf be at the bottom of the ranking order, and such individuals are perhaps better suited for constant displays of active and passive submission than they are for living alone. For wolves, camaraderie— no matter what the form— is preferable to solitude, and, indeed, submissive wolves tend to choose low rank over potential starvation.

All data on this page was taken from http://en.wikipedia.org/wiki/Wolf