Ever wonder if your man knows how to treat a lady? Well, before you commit to happily ever after, just look at his fingers.

According to a bizarre new study, men with short index fingers and long ring fingers are on average nicer towards women. This digit ratio stems from the hormones, mainly testosterone, they have been exposed to in their mother's womb. Researchers at McGill University now suggest that this has an impact on how adult men behave, especially with women.

"It is fascinating to see that moderate variations of hormones before birth can actually influence adult behavior in a selective way," co-author Simon Young said in a statement.

While past research has actually already studied the relationship between finger length and adult behavior, the McGill team is the first to highlight how it pertains to interactions with women.

During the study, researchers questioned 155 male participants on their interactions with people over the course of 20 days.

Overall, men with small digit ratios reported approximately a third more agreeable behaviors and approximately a third fewer quarrelsome behaviors than men with large digit ratios.

"When with women, men with smaller ratios were more likely to listen attentively, smile and laugh, compromise or compliment the other person," said Debbie Moskowitz, the study's lead author.

This is true for women who are not only girlfriends or wives but just friends or colleagues as well. The studied men were also less quarrelsome with women than with men, whereas the men with larger ratios were equally quarrelsome with both.

Researchers not only revealed the underlying biology as to what drives men to treat women in a nice, respectable manner versus the opposite, but also explain why these men tend to have more children.

So before your man tries to put a ring on it, take a look at his hands.

The results are described further in the journal Personality and Individual Differences.

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