A new study reveals that men who are extroverted and emotionally stable have more sexual partners. However, it turns out that the only quality that makes women more attractive to men is agreeableness.

The largest ever study conducted by behavioral economists in Australia looked into personality, sexual activity, and offspring of 4,500 heterosexual people. It found that men with more varied personalities tend to have more sexual partners and offspring.

Dr Stephen Whyte, one of the three researchers behind the study, explained how being the life of the party seems to be the only character trait both genders find sexually compelling: “For both men and women, extraversion equated to greater sexual frequency… We found key personality differences between the sexes in both sexual frequency and offspring success. Compared to females, males report a larger number of personality factors that influence such outcomes, which explains a greater proportion of the variation in sexual activity.”

Science doesn’t really have a firm understanding of how personality traits influence sexual activity—and certainly doesn’t extend to what personality traits we find attractive—so this is one of the first studies to shine a scientific light on who we have sex with and why. Although researchers interviewed twice as many men as they did women, they found that the positive correlation between extroversion and intensified frequency of sex was consistent across gender lines. But only men were at an advantage if they showed signs of a varied and agreeable character.

The study was based on the Big Five personality traits; extroversion, agreeableness, conscientiousness, neuroticism, and openness to new experiences. Dr Whyte added that certain combinations of the Big Five traits, including high extraversion and low openness, also appeared to correlate with increased offspring for males.

It might seem obvious that men who are well-rounded, nice human beings are going to appear more attractive to women, but when researchers explored what character traits men find attractive in women, the only key indicator researchers could find was agreeableness—being warm, friendly, tactful, and generally getting on with other people well.

“Our findings suggest that the greater variance in male traits and their particular combinations may provide an advantage for them when it comes to sex and reproduction but that doesn’t appear to be the case for the women we analyzed,” Dr Whyte added.