SACRAMENTO, Calif. – Ever marvel at that soft-spoken guy, a tad nerdy, who always seems to be surrounded by adoring women?

Well, there could be some scientific reasoning behind the attraction of low-key males over the brassy swagger of the loudest guy in the bar.

A University of California, Davis, graduate student who studied mating among 325 bison found the quietest bulls scored more mates and offspring than the most bellicose bellowers. The least successful bulls were actually 50 percent louder than their more prolific counterparts.

Does it mean anything for the lippy human male?

Researchers held off on drawing that conclusion – at least for now – because there would have to actually be experiments on humans, said Megan Wyman, the graduate student and lead author on the published study.

“The tricky part is setting up that experiment,” Wyman said. “You definitely need some good studies on that one, some pretty fun ones.”

After tracking and recording wild bison during two summers in Nebraska, researchers were able to conclude for the first time that “amplitude,” or loudness of communication, is significant in animal mating rituals. Previously, scientists focused on other aspects of mating communication, such as pitch or duration, Wyman said.

So, if rock-star “amplitude” doesn’t attract female bison, what does?

Wyman said that maybe there is a significant cue the bulls are conveying to the females about their “high quality.” The bulls don’t have to be loud, only heard.

“The big question is, why don’t the louder ones bellow softer?” she said.

Wyman’s theory is that the bigmouths are actually weaker and they fear stronger males who might draw close if the noise level is too low. Then there would be fights.

It sounds like the premise for a bad Seth Rogen movie, but it’s still a theory that needs more research, Wyman said.

All the research into bison communication was published in the November issue of the Association for the Study of Animal Behaviour’s journal.

Wyman and other researchers followed the bison who were branded as calves in the Fort Niobrara National Wildlife Refuge during the July and August mating season. They recorded each “hook-up” and took DNA samples from calves to confirm parentage.

She relied on 408 readings from a hand-held sound-level meter taken from 44 bulls.

The sound-level meter, relatively inexpensive to use for research, is the same type used to measure human voices, she said.

Say, at a party or in a bar.