>> How about couples in a monogamous relationship - is that natural? There's some evidence that while short-term(a few years) monogamy is natural , long-term o

>> How about couples in a monogamous relationship - is that natural? There's some evidence that while short-term(a few years) monogamy is natural , long-term one isn't . this book talks about it: http://www.amazon.com/Sex-Dawn-Stray-Modern-Relationships-ebook/dp/B007679QTG/ref=sr_1_1?s=books&ie=UTF8&qid=1436740178&sr=1-1&keywords=Sex+at+Dawn%3A+How+We+Mate http://www.amazon.com/Sex-Dawn-Stray-Modern-Relationships-eb...