According to a new study, men said they felt less inclined to use a condom for casual sex with women they found more attractive, and more inclined to use a condom with less attractive women.

What's more, half believed a more attractive woman was also more likely to have an STD, yet they were still likely to have unprotected sex with her. Stay classy.

Evolutionary instincts are strong at play here. As the study authors told The Washington Post, men could simply want to reproduce with more attractive women—a condom would just get in the way—or they could be trying to achieve a higher social status by having sex with more attractive women.

The study was small—only 51 heterosexual men were surveyed—but it still indicates that the thought process about safe sex is not as rational as: "I don't want an STD. Therefore, I will wear a condom."

But, you know, that's not a bad thought process to implement.