At his very core and essence, men has not change since the Ice Age.
As compared to the fairer gender, men has steadfastly held on the the concept of simplicity, and outright rejected all complexities that women bring to the table.
To understand men, all you need to know are three things, and believe, even in another thousand years, this will still hold true.
(Note: Read this in an "ugh ugh", Neandarthal "Cavemen" style)
1. Men like food. Preferably with meat.
2. Men like sex. Prefarably with women.
3. Men like sports. Preferably without women.
So go forth, all ye woman who claims that your men are difficult to understand, and have a more understanding and loving relationship.