men's facial hair was split into four categories, each differing in the thickness and coverage: very light, light, medium, and heavy. Light facial hair was rated as the most attractive, followed by medium, heavy, and the least attractive was 'very light'. This study suggests that some facial hair is better than none because it shows masculine development, as beard growth requires the conversion of testosterone. The study only examined the facial hair of brown-haired European males, so the results may not represent men of all ethnicities and hair colours. A different study found women are more attracted to clean-shaven faces than bearded faces. Jawline An attractive male jaw angle may have the following features: 115-130° in profile view interregional width similar to facial width vertical position in frontal view at the corners of the mouth or at least not below the lower lip jawline slope in frontal view nearly parallel to (with a maximum 15° downward deviation from) a line extending from the lateral canthus to the alare ascending ramus slope 65°–75° to the Frankfurt horizontal visible curvature in oblique view Because it generates the gonial angle, the ramus has a function in attractiveness. The gonial or jaw angle is the angle formed by the ramus and the rest of the mandible. It can range from 90 to 140 degrees, with the population average being 128 +/- 2.36 degrees for males and 126 +/-2.41 degrees for females. Larger, more obtuse gonial angles result in a rounder, feminine appearance, whereas more acute gonial angles result in square, masculine faces. This exact ratio is not seen as ideal in every ethnic group. Most research shows that attractive bigonial width and Ramus measurements have similarities, but the jutting square chin is a prominently European-heritage trait which means it should not be held as a universal indicator of attractiveness. Men with low submental fat were viewed to have "better jawlines" and a more "youthful look". Female-specific factors Research indicates that heterosexual men tend to be attracted to young and beautiful women with bodily symmetry. Rather than decreasing it, modernity has only increased the emphasis men place on women's looks. Evolutionary psychologists attribute such attraction to an evaluation of the fertility potential in a prospective mate. Facial features General Research has attempted to determine which facial features communicate attractiveness. Facial symmetry has been shown to be considered attractive in women, and men have been found