Is Earth old enough for DNA to evolve?

I think you picked the wrong target with humans. I understand why you picked us - it,s because you think that humans are important and special, but actually, in evolutionary terms we're merely interesting ( to ourselves). If you want to make the argument you are making, why not pick a flower... http://www.telegraph.co.uk/...w-growing-mountain-flower.html

One of the smallest animals - an amoeba - has 670 bn base pairs.But the relationship of base pairs and genes is not straightforward either. Humans have 3bn base pairs but only 30,000 genes, whilst a worm has 'only' 97m base pairs but 19,000 genes.Life is not easy to work out - it doesn't do straight lines.Sizing up genomes: Amoeba is king

It's great that you're showing an interest but why now and why genetics? I'm assuming you're here on this particular forum because it's related to a religious question?Genetics and the sciences and technologies that support its study are very, very new - we're only just beginning to know anything about it really. But already it's absurdly complicated; unless you're exteremely bright and very determined, you're extremely unlikely to get to a position where you can argue cogently about it with someone who actually KNOWS.For me it's like big physics or advanced mathematic, there comes a point very early on when you simply have to accept what you are being told by those that have spent their lives working in the field and read about it in the popularising literature.What astounds me is that people with absolutely no knowledge of the subject come here and tell us it's wrong. They need to aquire a little humility. (I'm not referring to you here - there's nothing wrong with asking questions.)If you're looking for a good, readable, book on evolution generally, I'd recommend Steve Jone's Almost like a whale. it's a re-write of Darwin's Origin of Species using up to date examples - including genetics, which Darwin had no idea about.

You're correct of course - genetics is not as intellectually impossible as I find big physics; someone (probably a physicist) said that all sciences apart from physics is just stamp collecting. And the general idea of evolution is startlingly simple and totally understandable to those who don't instantly reject it for religious reasons. You can even now prove it to yourself by simply visiting a good museum.But I get very lost, very quickly in the intricacies of molecular biology which is where this stuff inevitably takes you and where the big new stuff is happening.