“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.”

“Incidentally, the long-held idea that spices were used to mask rotting food doesn't stand up to much scrutiny. The only people who could afford most spices were the ones least likely to have bad meat, and anyway spices were too valuable to be used as a mask.”

“I mention all this to make the point that 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 extremely salient point: we have been chosen, by fate or Providence or whatever you wish to call it. It's an unnerving thought that we may be living the universe's supreme achievement and its worst nightmare simultaneously.Because we are so remarkably careless about looking after things, both when alive and when not, we have no idea-- really none at all-- about how many things have died off permanently, or may soon, or may never, and what role we have played in any part of the process. In 1979, in the book The Sinking Ark, the author Norman Myers suggested that human activities were causing about two extinctions a week on the planet. By the early 1990s he had raised the figure to about some six hundred per week. (That's extinctions of all types-- plants, insects, and so on as well as animals.) Others have put the figure ever higher-- to well over a thousand a week. A United Nations report of 1995, on the other hand, put the total number of known extinctions in the last four hundred years at slightly under 500 for animals and slightly over 650 for plants-- while allowing that this was "almost certainly an underestimate," particularly with regard to tropical species. A few interpreters think most extinction figures are grossly inflated.The fact is, we don't know. Don't have any idea. We don't know when we started doing many of the things we've done. We don't know what we are doing right now or how our present actions will affect the future. What we do know is that there is only one planet to do it on, and only one species of being capable of making a considered difference. Edward O. Wilson expressed it with unimprovable brevity in The Diversity of Life: "One planet, one experiment."If this book has a lesson, it is that we are awfully lucky to be here-- and by "we" i mean every living thing. To attain any kind of life in this universe of ours appears to be quite an achievement. As humans we are doubly lucky, of course: We enjoy not only the privilege of existence but also the singular ability to appreciate it and even, in a multitude of ways, to make it better. It is a talent we have only barely begun to grasp.We have arrived at this position of eminence in a stunningly short time. Behaviorally modern human beings-- that is, people who can speak and make art and organize complex activities-- have existed for only about 0.0001 percent of Earth's history. But surviving for even that little while has required a nearly endless string of good fortune.We really are at the beginning of it all. The trick, of course, is to make sure we never find the end. And that, almost certainly, will require a good deal more than lucky breaks.”

“We are so used to the notion of our own inevitability as life’s dominant species that it is hard to grasp that we are here only because of timely extraterrestrial bangs and other random flukes. The one thing we have in common with all other living things is that for nearly four billion years our ancestors have managed to slip through a series of closing doors every time we needed them to.”

“[Americans] were, for one thing, so smitten with the idea of progress that they invented things without having any idea whether those things would be of any use.”

“Even the simplest things had a glorious pointlessness to them. When buttons came in, about 1650, people couldn't get enough of them and arrayed them in decorative profusion on the backs and collars and sleeves of coats, where they didn't actually do anything. One relic of this is the short row of pointless buttons that are still placed on the underside of jacket sleeves near the cuff. These have been purely decorative and have never had a purpose, yet 350 years later on we continue to attach them as if they are the most earnest necessity.”

“It is not as if farming brought a great improvement in living standards either. A typical hunter-gatherer enjoyed a more varied diet and consumed more protein and calories than settled people, and took in five times as much viatmin C as the average person today.”