'Gaydar' Real, at Least For Women?

I am comfortable with the notion that people generally, and the women in this study, can deduce with a better than random chance which men are gay and which are not. My question is if this is from some sort of self identifying among gay men (even if subconscious), there are physical traits that gay men share (not necessarily exclusively among them, but more prominent by percentile then among strait men), or if there is some feature exclusively among gays which women pick up on subconsciously.

http://www.dailymail.co.uk/sciencetech/article-2007337/Gaydar-Women-really-tell-sexuality-just-looking-man.html

"If a woman tells you she can spot a gay man just by looking at him, don’t dismiss her claim out of hand.

Scientists say women really do have ‘gaydar’, which helps them spot whether a man is straight or gay just by looking at his face.

And the instinct is at its strongest when she is at her most fertile and in the mood for romance.

Their findings suggest that a woman’s ability to determine whether a potential male partner is straight or gay is linked to the impulse to have children.

During the three experiments, some 40 heterosexual women were shown a set of photographs of 80 men’s faces, all with the same expression.

Researchers found women were remarkably adept in being able to spot the gay and straight men.

But in a similar experiment using photographs of gay and straight women, they were less able to differentiate."