Confident and cocky alpha males may think they could win the heart of any woman, but a new evolutionary study on the development of the modern family suggests quite the opposite.

When it comes to finding a mate, women may actually be hardwired to prefer meeker and gentler men over their more macho counterparts, according to evolutionary scientists looking into how the modern two-parent nuclear family came to be.

New findings, published in the Proceedings of the National Academy of Sciences, suggest that women may have played a key role in an ancient sexual revolution, and that if women had not started choosing good providers over the 'leader of the pack' as mates, humans may still have the sexual free-for-all social structure of the apes, with males constantly fighting each other for mating rights.

Researchers from the University of Tennessee, Knoxville, said that the 'sexual revolution' occurred when weaker, lower-ranking males who had no chance of winning a fight against stronger, more masculine males opted on providing food and care instead.

Lead author and evolutionary biologist professor Sergey Gavrilets said that this effect of the males attempting to "buy mating by providing for the female" was in turn reinforced by females who show preference for the low-ranked, "provisioning" male.

After a while, as more females began to choose good providers as mates, pair-bonding replaced promiscuity, which built the foundation for the emergence of the institution of the modern family.

Previously experts have struggled to explain how the modern family came to be, because they believed that if low-ranking males started providing food, the stronger ones would just fight them off, but until now researchers had not realized that female choice was the critical factor.

"Once females begin to show preference for being provisioned, the low-ranked males' investment in female provisioning over male-to-male competition pays-off," Gavrilets explained in a statement.

"Once the process was underway, it led to a kind of self-domestication, resulting in a group-living species of provisioning males and faithful females," he said.

While commonly accepted theories for the transition to human pair-bonding were not mathematically feasible.

However, the latest findings, based on a new mathematical model, which accounts for female choice and faithfulness as well as other factors, shows that the only scenario that appeared to push humans away from promiscuity, was that there was an increased emphasis on provisioning females over male competition, particularly from low-ranking males. 

"The study helps answer long-standing questions in evolutionary biology about how the modern family, characterized by intense, social attachments with exclusive mates, emerged following earlier times of promiscuity," the researchers said in a statement.

"In addition to the establishment of stable, long-lasting relationships, the transition to pair-bonding was also characterized by a reduction in male-to-male competition in favor of providing for females and providing close parental involvement," they added.

Gavrilets said that the study reveals that female choice played a significant role in human evolution and that future research should include between-individual variation to help explain social dilemmas and behaviors.