Thus, it is my analysis that the most beautiful females have the square jaw look. A square jaw look in female, being still very different than a typicall square jaw in males, notably in the chin area (very androgenic shaped zone).
Horizontal Growth
Horizontal growth is when the jaw grows "horizontally"; when the jaw plane seems
parallel to the floor. Jarah is a perfect example:
Here is structurally what happens:

On the left you have the face of an horizontal
grower.
On the right, you have the face of an ugly vertical grower. Do you know why a
same person often has big nose, thin face and receding + double chin ? It is because he is
a vertical grower.
You will find plenty of people around you that
exhibit both patterns.
Horizontal growth is the result of better orthodontic development, resulting in
a more beautiful appearance. "Healthy" is often synonym of "beauty".
This is another reason why I think, square jawed people are better developed, and more beautiful. In the case of this site i'm interested in women, not men but this proves that structural square jaw has nothing to do with femininity or masculinity. Horizontal growers = better breath, better spinal posture, no double chin.....

Typical vertical grower face. Now compare with
the face of Jarah above. Beauty equation should jump out of the screen.
It is shocking to realize how poor jaw growth is associated with typical
ugliness pattern: weak chin, double chin, prominent nose, thin face, bad spinal
posture, crowded teeth......
Again, not ALL square jawed women are beautiful, but well developed square jaw is a health -> beauty attribute that will influence many other aspects of a person's appearance.
More on this fascinating topic here: http://www.fasttraxortho.com/when_to_begin_treatment.htm