Isn't being against gay marriage the same as being against african americans voting back in the 60's?

I read the article about Miss Beverly Hills and Miss California from last year denouncing gay marriage as being against the Bible and against God. But isn't that just one of those things that needs to be updated with the times? The bible was written 2000 years ago (well, 1900 or so), and back then, stoning women for having a child out of wedlock was commonplace and yet I don't hear radical christians screaming for the death of single mothers?