Some of us may have naively thought that a 50/50 split in doing house chores, child rearing and earning money for the family is the best practice for humans. But I think many of us who adopted the traditional arrangement with a modern twist have better results when it comes to the level of happiness for all members of the family. The modern twist I am referring to is the compromise to incorporate modern realities like the need for additional income and more opportunities for women in the workforce.
Explanations why fair does not necessarily mean equal include differences in the biology of each gender, including differences at the level of the brain to the level of manifested behavior (heard of "equal but different"?), cultural and religious tenets and conventional wisdom.
Now, economics has something to say on how to the divide work between spouses to improve the chances of a happy life together. The concept of comparative advantage is raised as one main consideration on modern arrangements that work.
Watch this video as an introduction to a new book Spousonomics: Using Economics to Master Love, Marriage and Dirty Dishes, which is available at Amazon (click on the book icon to the left to learn more).
Got the heads-up from a Yahoo article Economics: the key to happy couples' division of labor that featured this book and video.