I count seventeen in-focus faces, of which fifteen are female and two are male.
We don't actually have 8½ times as many female students as male students, so why the disparity?
I guess more male students could have declined to allow their photographs to appear in the ECS, but I can't think why they would do this.
Perhaps the idea is to attrract more young women to go to university by showing them role models, but 56% of Essex University's students are female and 44% are male; it would make more sense to give male students role models.
Maybe they do want to attract more young men to go to university by showing them the abundance of young women they will encounter there. That's rather too subtle for the ECS, but remains a possibility.
The actual answer, I suspect, is that female students are deemed more photogenic than male students.
Well, either that or the photographer has a thing for women in their early twenties.