I just googled "male and female skull differences" to see if it could be easily determined whether this skull is male or female. Here are a couple of articles that shed light on the subject:
http://www.landofskulls.com/site/1534698/page/893371
http://www.secondtype.com/skeleton.htm
First of all, they say that determining gender of a skull is quite difficult because there is some overlap in characteristics from male to female.
Having said that, what I found that might be helpful is that a female has a sharper supraorbital margin (i.e., the upper ridge of the eye socket). Looking at this skull, it appears that the supraorbital margin is quite sharp, which would suggest to me (
in my very un-expert opinion) that the skull is female.
Male and Female Cranium Differences
Most important skull differences between men and women are indicated by the letter value on the figure above and described below:
A) The mans cranial mass is more blocky and massive compared to the females which is rounder and tapers at the top.
B) Temporal Ridge - runs along the outer side of the upper skull creating the square shaped of the upper head. More prominent in men than women.
C) A woman's supraorbital margin (the ridge above the eyes) is sharper, while the males is rather round and dull.
D) The Zygomatic bone (the cheekbone that lies under the lower eye ridge) is more pronounced on the male skull.
E) The Mandible (lower jaw) bone of a woman is rounded, while the male's is squared.
F) Frontal bone – forehead structure terminates at the brow. The male forehead is lower and more slopping.
G) Men have a deeper cranial mass.
H) The supercilary arch is large and pronounced in the man.
I) A males gonion (most posterior inferior point on angle of mandible) is more flared out and sharply angled.
J) The teeth of men tend to be larger.