According to the Economist, Penn State anthropologist David Puts has concluded that "almost all of the traits considered to be masculine-big muscles, facial hair, square jaws, deep voices and a propensity to violence-evolved [...] specifically for their usefulness in fighting off or intimidating other men." In some species, the Economist explains, males don't fight for females, instead developing attractive markers of genetic quality so that females will choose them (one example of this is the pickup artist's favorite animal, the peacock). But peacock-style males are usually the same size as or smaller than females, while human males are larger, like gorillas, who tend to fight for mates. And heavy eyebrows, deep voices, and facial hair may have evolved to scare rivals, while big jaws developed to take a punch. Puts allows that female preferences may have had something to do with the evolution of these traits, but only insofar as women wanted to have sex with fightin' men so that their kids would also be awesome fighters.
Puts apparently "emphasises that evolutionary biology is not destiny" and that "in modern societies men and women freely choose their mates" — but a preference for violent or at least competitive men may persist in the form of stereotype. According to Tom Bartlett of the Chronicle of Higher Education Percolator blog, researchers in a second study taped men and women responding to job interview questions in a modest manner — answering an inquiry about salary expectations, for instance, with the words, "Well, if I should be lucky enough to get the position, I'm sure you'd offer me a fair wage." When men and women watched the tapes, they both disliked the male applicants more than the female ones, even though they gave the same answers. Bartlett quotes from the study:
Changes in gender roles that have afforded women more financial independence have not yielded relaxed demands for men. That is, men are still required to uphold masculine ideals that require chronic exhibitions of strength while avoiding signs of weakness.
"Chronic exhibitions of strength" is a funny way to put it, but also a pretty good formulation of the unrealistic and pointless expectations society has of men. But lest you think this research is all about men and their problems, Bartlett hastens to point out an earlier study by the same team, which found that women who behave assertively are seen as having poor social skills, and that they're less likely to be hired even if judged competent (you mean women can't get ahead just by acting like men?). The Economist mentions that Puts's study hearkens back "to old stereotypes about violent cavemen battling with clubs while a passive woman, fetching in furs, waits helplessly to see who will win her" — looks like the modern workplace does too.