I come Des Moines. Somebody had to.

When you sit in a chair, you are not actually sitting there, but levitating above it at a height of one angstrom (a hundred millionth of a centimetre), your electrons and its electrons implacably opposed to any closer intimacy.

You may not feel outstandingly robust, but if you are an average-sized adult you will contain within your modest frame no less than 7 X 10^18 joules of potential energy—enough to explode with the force of thirty very large hydrogen bombs, assuming you knew how to liberate it and really wished to make a point.

No one knows, incidentally, why Australia's spiders are so extravagantly toxic; capturing small insects and injecting them with enough poison to drop a horse would appear to be the most literal case of overkill. Still, it does mean that everyone gives them lots of space.

"Croissant": However you choose to pronounce it at home, it is perhaps worth nothing that outside the United States, the closer you can come to saying "kwass-ohn," the sooner you can expect to be presented with one.

Every atom you possess has almost certainly passed through several stars and been part of millions of organisms on its way to becoming you. We are each so atomically numberous and so vigorously recycled at death that a significant number of our atoms-up to a billion for each of us, it has been suggested-probably once belonged to Shakespeare. A billion more each came from Buddha and Genghis Khan and Beethoven, and any other historical figure you care to name.

If you were designing an organism to look after life in our lonely cosmos, to monitor where it is going and keep a record of where it has been, you wouldn't choose human beings for the job. But here's an extrememly salient point: we have been chosen, by fate or Providence or whatever you wish to call it. As far as we can tell, we are the best there is. We may be all there is. It's an unnerving thought that we may be the living universe's supreme achievement and its worst nightmare simultaneously.