Just after reading the last few posts in this thread, something came to my mind so I'm going to post it here. I don't know if it's relevant or if anyone cares, it's just a thought I was having recently.
It's amazing how complex yet how simple and how perfect systems on earth work. I was watching Planet Earth, and they were talking about how if bees stopped pollenating our plants, we would either have to starve or intervene ourselves and pollenate plants ourselves. The estimated cost of doing this would be hundreds of billions of dollars. It currently costs us nothing because bees do it for us. It's just amazing how simple that is.
It's a new thing that the Discovery channel is doing. It's like a super documentary of our planet, there's all sorts of rare footage shot with super awesome cameras and shit.
If so, then it's the same one I'm on about. It's an amazing series. I got the DVDs of both series for Christmas (as well as having watched them on TV) and I have to say, on a HDTV it looks stunning.
I don't know how far into the whole thing you are, but have you seen the episode on Caves? That one has to be my favourite.
EDIT: Looks like they've changed the narrator for you folks. We had David Attenborough. I wonder if the episodes are the same, or different.