I watched David Attenborough's Planet Earth last night and couldn't believe that the polar bear died. For anyone who didn't see it, a polar bear died. I'd heard some of his battle with the walruses beforehand on the radio but I thought being a big strong polar bear and them being little walruses (I didn't realise how massive they were until I saw them next to the polar bear) he'd get something to eat. There were lots of walruses and only one bear, it just seems so unfair. I know it happens all the time in nature: that's what life is; animals kill each other to live and those that can't kill or find food die. Survival of the fittest and all that. The polar bear hadn't been able to get any dinner and was injured in his fight with walruses. He knew then that he was going to die, he curled up in the snow and made a little nest for himself and went to sleep.

It was especially sad after he'd swam for two days to try and get some food and even more sad that the reason he had to swim so far and wear himself out is because of us and our use of carbon which has heated up the earth and made the ice caps melt. Grrrr. Humans make me so angry, and sad.

I know lots more polar bears are going to die because of us and if it takes images of cute polar bears dying for us to stop and think about what we're doing then I suppose that's a good thing. But I just don't have the faith in human nature. I don't think people care enough. I know they don't care enough. They just think about themselves and their little world. Like I do. How many blogs have I devoted to myself? To my life. I'm just one person but like a lot of other people, I think the world resolves around me.

I went on the climate change march in London on Saturday. There were speeches beforehand about how we CAN make a difference and how it's not too late. But I just can't convince myself. There were about 20,000 people on the march, more than expected, but there were about 150,000 on the biggest anti-war march I went on and what difference did that make?