Joshua Rosenau spends his days defending the teaching of evolution at 
Via BoingBoing, we find this graphic
by Adam Nieman/Science Photo Library. On the left, a globe with all the water collected into a tiny marble, and on the right, a globe with all the air collected into a marble.
We think of ourselves occupying the globe, but really, those two tiny spheres are all we can do anything with, and only a fraction of each is accessible. No new water is being created, and no new air is being generated (though it is stored, recycled, and reprocessed in various ways). That's all we've got, all our children will have. It's a precious heirloom, and we need to take care of it.
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