Sep 15, 2010 10:10 GMT  ·  By
Rendering of male faces, displaying either low-testosterone, high-cortisol levels (left), or low-testosterone, low-cortisol levels
   Rendering of male faces, displaying either low-testosterone, high-cortisol levels (left), or low-testosterone, low-cortisol levels

In a very interesting finding, researchers discovered that females in a study group appeared to prefer calmer, chill guys over their more active and on-the-go peers.

The conclusion comes as a surprise for many scientists, as it contradicts some past investigations, but the new conclusions actually make a lot of evolutionary sense.

That is to say, experts discovered that men who are calmer tend to have lower levels of the hormone cortisol, which has been directly linked to stress levels.

In the long-run, being less stressed out has many reproductive advantages. Males that are filled with this chemical, as well as with testosterone, are a good choice at first only.

Over the years, the advantages they carry – offering better protection for offspring, for example- dwindle when compared to the advantages provided by chill men.

Previous investigations showed that testosterone-laden men should be especially attractive to women, because the hormone is associated with masculine traits.

In the long run, men with a lot of the chemical in their systems are indeed more aggressive, but also healthier, and more capable of protecting their offspring.

But there are also numerous disadvantages to exhibiting large levels of the hormone, which apparently make these males less attractive in the eye of women than researchers expected.

One of these negative points is the fact that such males tend to lead a more libertine lifestyle, which is not necessarily good if he wants to settle down and be a good parent. While exceptions exist, they are rare, experts have determined.

Another important drawback is the increased level of cortisol, the stress hormone that affects the functions of the immune and reproductive system.

As such, resulting offspring may not be of the best quality, says University of Abertay Dundee human behavioral ecologist Fhionna Moore, quoted by LiveScience.

Women appear to be natively aware of this, as they do tend to prefer men who exhibit lower levels of cortisol, which is to say they choose those who are calmer over all.

“We speculate, then, that males with low cortisol possess something desirable that women seek to secure for their offspring. This could be, for example, good health or a healthy response to stress,” the team leader says.

“We tend to interpret women's preferences as reflecting those for cues to the characteristics that make a man a good long-term partner,” she adds.

“I can speculate that high-testosterone, high-cortisol levels may signal someone who is dominant and may make a good provider – high testosterone is certainly likely to be related to this,” Moore argues.

Details of the Scottish team's work appear in the September 15 online issue of the esteemed scientific journal Proceedings of the Royal Society B.