WHR values for <i>Playboy</i> centerfold models (in yellow) and winners of 4 <i>Miss</i> pageants (<i>Miss America</i>, <i>Miss World</i>, <i>Miss Earth and Miss Universe</i>, in blue) by time of magazine appearance or victory.

<p>The data were fit by a linear regression that includes a quadratic term (in red).</p

Plot of WHR values for artworks (in gray), <i>Playboy</i> centerfold models (in yellow) and winners of <i>Miss</i> pageants (in blue) according to time.

<p>The best model parameterization was as follows: WHR = 0.74 during the <i>antique</i> period and WHR = 0.99 <i>-</i> 0.015<i>*</i>T during the <i>recent</i> period (in red).</p

Example of facial features for the four women appearing in a quartet in Study 2.

<p>The rater’s traits were recorded in the computer program. Then, the four faces of the same virtual woman were presented, depending on the rater’s own traits (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049791#pone-0049791-g002" target="_blank">figure 2</a>). An example for a rater with light eyes, no chin dimple, dark hair, thick eyebrows and thin lips.</p

A typical screen shot during the evaluation of the women’s facial features by the raters in Study 1.

<p>Women aged 18–25 were recruited and three facial photographs (triptych) were taken. A computer program was used to randomly present drawn pairs of triptychs to male raters. For each pair, the rater had to click on the picture depicting the woman that he found the most attractive. The pictures and information were used with each woman’s consent for publication.</p

Men’s Preference for Women’s Facial Features: Testing Homogamy and the Paternity Uncertainty Hypothesis

<div><p>Male mate choice might be based on both absolute and relative strategies. Cues of female attractiveness are thus likely to reflect both fitness and reproductive potential, as well as compatibility with particular male phenotypes. In humans, absolute clues of fertility and indices of favorable developmental stability are generally associated with increased women’s attractiveness. However, why men exhibit variable preferences remains less studied. Male mate choice might be influenced by uncertainty of paternity, a selective factor in species where the survival of the offspring depends on postnatal paternal care. For instance, in humans, a man might prefer a woman with recessive traits, thereby increasing the probability that his paternal traits will be visible in the child and ensuring paternity. Alternatively, attractiveness is hypothesized to be driven by self-resembling features (homogamy), which would reduce outbreeding depression. These hypotheses have been simultaneously evaluated for various facial traits using both real and artificial facial stimuli. The predicted preferences were then compared to realized mate choices using facial pictures from couples with at least 1 child. No evidence was found to support the paternity uncertainty hypothesis, as recessive features were not preferred by male raters. Conversely, preferences for self-resembling mates were found for several facial traits (hair and eye color, chin dimple, and thickness of lips and eyebrows). Moreover, realized homogamy for facial traits was also found in a sample of long-term mates. The advantages of homogamy in evolutionary terms are discussed.</p> </div

The raters' choices according to the artificial faces hypotheses in Study 2 (See figure 2). The raters predominantly preferred faces similar to their own.

<p>The raters' choices according to the artificial faces hypotheses in Study 2 (See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049791#pone-0049791-g002" target="_blank">figure 2</a>). The raters predominantly preferred faces similar to their own.</p

Table. 2. Testing the homogamy and the paternity uncertainty hypotheses, according to raters and women’s phenotypes.

<p>Predictions are coded as follows: the first letter indicates the phenotype of women preferred, and the second the rater’s phenotype. Thus “DD>RD” corresponds to the hypothesis “the preference of phenotypically dominant men towards phenotypically dominant women is stronger than the preference of phenotypically recessive men towards phenotypically dominant women”. <i>P</i>-value for each trait and overall are presented. Bold <i>P</i>-values highlight significant (<i>P</i><0.05) results.</p