Republican Rep. Jay Rodne of North Bend opposes same sex marriage in our state:

"There's been no compelling justification to abandon traditional definition of marriages, as has existed in human civilizations since time immemorial."

So on Seattle's Morning News, we wanted to know: How HAS marriage existed since time immemorial?

Evergreen State College history professor Stephanie Coontz, author of Marriage, A History, told us that marriage has changed constantly.

"The single most traditionally preferred form of marriage throughout history, in more cultures than any other, is not 'one man, one woman' but 'one man, MANY women.' That's the type of marriage mentioned most often in the first five books of the Bible."

OK, but how about the Christian era?

"Christianity was the first religion to say that being able to procreate had nothing to do with what makes a marriage valid. When Jesus said you should not be able to divorce, that reversed thousands of years of the idea that you should be able to take another wife or divorce your wife if she could not have a child."

Other recent marriage developments include: Choose your own partner. Love instead of property arrangement. Men not owning all the marital assets. "Mandatory" fidelity. Women working outside the home. Birth control. Artificial insemination. (I also change a lot more diapers than my dad did.)

OK, so marriage has always evolved. But do those changes erode the institution? Coontz told us that in Nordic and European countries, divorce and non-marriage rates have recently leveled off, even though same-sex marriage has been approved there. Not that same-sex marriage gets the CREDIT; just that she doesn't see this most recent marital update causing marital crumbling.

Listen to How traditional is American marriage?