(FORTUNE Magazine) – In the dangerous, hairy, backbiting world of baboons, the struggle to attain alpha-male status and power is all about sex. Unlike gibbons, who mate for life, or bonobos, who scurry off to the intimacy of the bushes on every possible occasion (they mate in celebration, relief, fear, boredom, etc., etc.), baboons live in well-developed hierarchies and get it on according to rank. Alpha males, it is typically assumed, have about 50% of all the sex in a tribe; low-ranking peons spend a lot of time moping.

This strict sex/power pyramid creates the perception that baboon life is the "most extreme example of a male-dominated, chest-thumping society in the primate world," according to Stanford primatologist Robert Sapolsky. And in many ways it is. But scientists like Sapolsky are now finding that the traditional macho view hardly does baboon life justice. The reality is much more subtle and complicated, and it raises a host of questions about what it means to be an alpha--or a beta or a female--in any complex, hierarchical system.

Sapolsky is one of the world's foremost primatologists (and funniest--he describes a particularly bad-looking baboon as resembling a "dissipated, fin-de-siecle neurotic") and the author most recently of A Primate's Memoir, on his experiences studying baboons in Kenya. When FORTUNE caught up with him in his Stanford office to talk about the changing perception of alphaness, he was just finishing up a meal of organic chili with vegetables eaten from the can.

Not only is the average brutish alpha likely to "go down in a hail of bullets," Sapolsky explained, but scientists are now finding that even the most successful alphas are often out-reproduced by lower-ranking males who have taken up "alternative strategies" to tribe life. Modern primatology has uncovered surprisingly strong reproductive rates among male baboons who have dropped out of the male-male nonsense altogether. Those "highly affiliated nice guys"--who went largely unstudied during what Sapolsky calls the "idiot, caveman, chest-thumping era of primatology"--spend most of their time hanging out with the females, picking bugs out of each other's fur, and playing with the kids. And, when the alpha isn't looking, scuttling off to the bushes with his best girl for what has become known as "sneaky copulation."

For anyone interested in the natural state of the alpha male--or, for that matter, of the love affair--there are interesting conclusions to draw from this. "People are realizing that there is a tremendous amount of female choice in these troops," Sapolsky says. "And female choice is built around male-female affiliation rather than the outcome of male-male aggression. It's this totally bizarre discovery that females like to hang out with guys who are nice to them."

The males having gal-pal sex aren't just ineffectual branch potatoes. Often they are animals who have made it some distance up the baboon ladder--even in some cases all the way to the alpha position--and then had something like a revelation. They've won a few fights, looked around, and decided that the hypercompetitive hierarchy thing just isn't for them. They downshift. They make a lifestyle change. Their overall health improves immensely, they make some friends, and they have a better chance of knowing who their kids are.

Becoming a highly sexed, noncompetitive baboon, however, is not as easy as it sounds. The average African savannah baboon is biologically hard-wired for the hierarchical lifestyle, and the species is not exactly prone to thinking outside the box. That's what makes the "alternative strategy" epiphany so interesting. How do the nice guys do it?

Sapolsky's hunch is that it has something to do with the frontal cortex, the part of the brain that manages impulse control and moral development. In humans it's what allows us to learn not to "burp during the wedding ceremony," Sapolsky says. He thinks varying levels of frontal cortex development probably account for the biggest differences between baboon personality types, allowing "alternative strategy" guys to walk away from a lifetime of fights--over a sneeze, or a particular spot in a limitless field of grass--that the average baboon couldn't resist.

The frontal cortex is also vital for those who remain in the dominance hierarchy. Impulse control can mean the difference between a successful alpha and a flameout. Most baboons can make basic strategy but lack the patience to execute. "They just can't prevent themselves from leaping out and doing some dumb-ass thing that blows their whole plan," Sapolsky says. The alphas who get to the top and stay there are "great at forming coalitions and being psychologically manipulating and physically intimidating, as well as using bluffs and suggestions of violence instead of actually getting into fights," he says.

Sound familiar? Like, for example, your office? "The baboon world is hugely relevant to human, Westernized competitive cultural models," Sapolsky says.

Especially with regard to stress: Primatologists and social scientists have turned up nearly identical data showing that the worst stress levels tend to occur in baboons and humans trying in vain to rise up the ranks. The best stress profiles occur among those who have exited the rat race altogether, and alpha males of both species tend to have mixed profiles --depending how secure their power is.

Before you start threat-yawning at co-workers, however, it's important to keep in mind that comparisons to these smelly, grunting primates can go too far. This is a species, after all, in which males who "want to say howdy" to friends will often, Sapolsky says, give a nonchalant yank on each other's penis. That's the kind of behavior that can make any human, from alpha males to alternative-strategy guys, thank God for the high-five. And, of course, three million years of beautiful evolution.