It is, however, simply not true.
Having said which, it used to be a serious scientific theory, derived from behavioural studies on captive wolves conducted in the mid 20th century. Better studies at the end of the century, looking at wolves in their natural habitats and not stressed by close confinement in zoo cages, revealed the truth: not only is the dominant female at least as important as the male, but the correct word for that dominant pair isn't "alpha", it's "parents".
That is, the supposed "betas", the males in the pack that aren't breeding, aren't weedy individuals hoping to build themselves up to prove their masculinity by challenging the "alpha male". They're just his children who haven't left home yet. While there certainly are mammalian species in which the male competes for dominance or monopolises mating opportunities through the force of his masculinity (most deer, for example), wolves are not among them.
The actual breeding system is a cooperative, family-based one, based around a monogamous pair. The younger individuals gain the benefit of pack-living, being able to cooperate to take down large prey, in return for which they help look after their younger siblings, taking the strain off their mother.
This likely evolved together with the tendency for wolf mothers to have large litters that might otherwise be too large for them to handle on their own. This puts the dominant female (that is, the pack mother) in the central position when it comes to determining mating opportunities, but, in practice, she's unlikely to be 100% succesful. The degree to which that's down to the sheer practicality of stopping your daughters from doing things you'd rather they didn't, and the degree to which giving older daughters some leeway ensures help with rearing younger pups, is open to debate.
While looking at wolves may be a bad guideline for human behaviour, it is much more likely to be relevant to the behaviour of their own close relatives. Large litters are a feature of many canid species, and it's therefore likely that many of them face the same pressures. Indeed, we find, when we look at the wolf's closest relatives, that, even if their hunting packs aren't usually quite so large, monogamy supported by wider cooperation is the norm among them.
When I'm talking about "wolves" above, the species I am referring to is technically the grey wolf (Canis lupus), the species that dogs were domesticated from, and that is usually referred to simply as a "wolf" in most parts of Eurasia and North America, where they live. In contrast, the African wolf (Canis lupaster) is a different species.
Previously thought to be a jackal, it was only raised to full species level in 2015, when it was split away from the golden jackal (Canis aureus) on genetic grounds. The name comes from the fact that it is more wolf-like than true jackals, and lives only in northern Africa, reaching as far south as Senegal and Kenya. Indeed, genetic evidence suggests that it may have arisen as a result of cross-breeding between grey wolves and another, Ethiopian, species (Canis simensis) in the distant past.
A long-term study of African wolves on the Serengeti, near the southern boundary of their range, began in 1977, and continues to this day. By now, this means that we have a large database of information that we can go back to and examine to see how packs evolve and interact, and how they change with time. One recent analysis looked into family interactions and asked what best contributes to parents raising more pups.
Between 1977 and 1990, the African wolves in the study area gave birth to a total of 36 litters. Just as with grey wolves, monogamous pairs formed the basis of the social structure, with each pair staying together for up to eight years, defending an area of 0.5 to 2 km² (125 to 500 acres). Packs are much smaller than in grey wolves, but, for twelve of the litters, the parents had at least some assistance from another adult wolf, bringing back food for the pups or for the lactating mother. There was usually just the one helper in these cases, although two or even three helpers were sometimes seen.
Having said which, some younger wolves just hung around in the territory without visibly being helpful, although it's possible that they helped defend the territory against rivals. Since they only tended to hang around for a single year, it's likely that they were using their parents' territory as a base from which to explore the surrounding area before striking out on their own.
Although litters typically result in the birth of up to six pups, as is often the case with wild animals, most do not survive until they can forage for themselves at 14 weeks. On average, each mated pair managed to successfully raise 1.17 pups per litter if they had no assistance. Since they will have several litters over the course of a lifetime and, on rare occasions, even two in a year, that's sufficient to maintain the population and grow it over the long term if resources allow.
But it's significant that it takes both parents to do this, and this is probably why African wolves (and most other canids) are monogamous in the first place. If the males each dominated a harem, or mated with several females and then left them to their own devices, the mothers would struggle to raise pups on their own. What works for deer or cats doesn't work for wolves; the father has to stay around and be helpful.
Indeed, there was one instance of a single mother during the study, a younger intruder who had evidently managed to mate with the dominant male, who was then far too busy with his partner's pups to help her with hers. All of her pups died, and so did she.
However, add in another adult wolf not breeding, but being seen to help feed their younger siblings, and things improve. That extra helper meant that, on average, 0.58 pups per litter survived for 14 weeks. Over the lifetime of the mother, that adds up to several more children reaching the age to have children of their own.
The advantage to this for the parents is obvious, but what are the helpers getting out of it? They are putting off leaving to find a partner and raise children of their own, they may risk injury defending territory that isn't really theirs, and they are even putting effort and resources into the task, potentially putting them at unnecessary risk should conditions suddenly get worse.
Well, for one thing, it probably helps that the pups they are assisting are their own siblings, whose survival could benefit their family genes in the long run. They may also receive reciprocal help from the parents when times get hard, and the practice of looking after pups may stand them in good stead when they do eventually leave. Also, by staying where they are, they may get the chance to keep an eye out for openings in neighbouring territories, should a member of an unrelated pair die and leave her partner looking for someone new.
It might, perhaps, be different if such situations occurred regularly. But, at least in the Serengeti during the years of this study, they arose only rarely. The main problem was simply the lack of territory - there was just nowhere for a new pair to set themselves up most of the time. This changed partway through the study when there was a local outbreak of canine parvovirus, reducing the total population. In the following years, young wolves were more likely to establish new territories and find a partner willing to share it with them, but it took a while to rebuild the population, partly because first-time parents don't gain the benefit of older children helping them look after young ones.
However, while African wolves will drive off rivals of the same sex from outside their territories, within their home communities, it's all about cooperation, not conflict.
[Photo by Giles Laurent, from Wikimedia Commons.]
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