When I awoke it was daylight. The inside of my tent was coated in a curious flaky rime, which I realized after a moment was all of my nighttime snores, condensed and frozen and pasted to the fabric, as if into a scrapbook of respiratory memories.

18th century scientists, the French in particular, seldom did things simply if an absurdly demanding alternative was available.

It isn't easy to become a fossil. ... Only about one bone in a billion, it is thought, becomes fossilized. If that is so, it means that the complete fossil legacy of all the Americans alive today - that's 270 million people with 206 bones each - will only be about 50 bones, one-quarter of a complete skeleton. That's not to say, of course, that any of these bones will ever actually be found.

I tell the kids that, even in a childhood marked by despair and deprivation, I knew that no matter what happened, I still had my family, or at least the remnants of a family ripped apart by divorce and then glued back together in various odd arrangements through a series of ill- advised remarriages. It was good to know I had a solid foundation.

As James Surowiecki noted in a New Yorker article, given a choice between developing antibiotics that people will take every day for two weeks and antidepressants that people will take every day for ever, drug companies not surprisingly opt for the latter. Although a few antibiotics have been toughened up a bit, the pharmaceutical industry hasn't given us an entirely new antibiotic since the 1970s.

The great failure in education, much of the time, is the lack of excitement and stimulus

So, if people didn’t settle down to take up farming, why then did they embark on this entirely new way of living? We have no idea – or actually, we have lots of ideas, but we don’t know if any of them are right. According to Felipe Fernández-Armesto, at least thirty-eight theories have been put forward to explain why people took to living in communities: that they were driven to it by climatic change, or by a wish to stay near their dead, or by a powerful desire to brew and drink beer, which could only be indulged by staying in one place.