Review

 I've just realised that I haven't posted my latest contribution to the Literary Review (not that I post them all) – a review of a mind-boggling new book by Henry Gee, A (Very) Short History of Life on Earth: 4.6 Billion Years in 12 Chapters. It went out under the apt title 'What Will Survive of Us?' Here it is...

‘Once upon a time…’ The opening words of Henry Gee’s new book give notice that what follows will be a story – and a dazzling, beguiling story it is, told at exhilarating pace. The scale is apparent from the first of a set of mind-boggling timeline graphics: this runs from the birth of the universe at the bottom of the page to ‘Extinction of life on Earth’, near the top, alarmingly close to the dotted line of ‘NOW’. This is a book to give you a new, dizzying perspective on such small matters as human civilisation. ‘Against the backdrop of geological time,’ Gee reminds us, ‘the rise of humanity is of negligible significance.’ We’ll be gone in a while, leaving barely a trace behind . The ‘carbon spike’ we have contributed to, and which causes us so much anxiety, is high but very narrow, ‘perhaps too narrow to be detectable in the very long term’. Besides, taking the long view, ‘life on Earth, with all its drama, all its comings and goings, is governed by just two things. One of them is a slow decline in the amount of carbon dioxide in the atmosphere. The other is the steady increase in the brightness of the Sun.’ Unlike carbon dioxide, oxygen might be thought of as an all-round good thing, essential to life on Earth. And yet it was a sudden surge of free oxygen that caused the Great Oxidation Event, unleashing the first of many mass extinctions that pepper the history of this planet. All that oxygen scrubbed the air of the carbon dioxide and methane that were keeping Earth warm and launched the first and longest ice age – 300 million years during which the planet became ‘Snowball Earth’, covered from pole to pole with ice. ‘And yet,’ observes Gee calmly, ‘the Great Oxidation Event and subsequent Snowball Earth episode were the kind of apocalyptic disasters in which life on Earth has always thrived.’ Eighty million years of ice ages only encouraged life to keep on coming back, sometimes in decidedly strange forms. I must admit I had never heard of Lystrosaurus, an animal with ‘the body of a pig, the uncompromising attitude towards food of a golden retriever, and the head of an electric can opener’ – and yet, for millions of years after the End-Permian mass extinction (yes, another one), nine out of every ten animals on Earth was a Lystrosaurus. Nor had I heard of stromatolites, mounds of slime and sediment that, early in the history of life on Earth, became ‘the most successful and enduring form of life ever to have existed on this planet, the undisputed rulers of the world for three billion years’. Dinosaurs, on the other hand, are animals that every child has heard of. These hugely successful creatures filled every evolutionary niche, leaving little room for much else, including the early mammals, who had to wait until the dinosaurs finally died out before they could ‘burst forth, like a well-aged champagne, shaken beforehand, and inexpertly corked’. A profusion of fast evolving and diversifying mammals took over from the dinosaurs. They included what Gee calls ‘a group of leftovers … an assortment of scrappers that included rats, mice, rabbits and, seemingly almost as an afterthought, the primates’. These small, fast-moving creatures with forward-facing eyes, inclined to curiosity and exploration, would, eventually, give rise to Homo sapiens. But the emergence of modern humans could so easily not have happened. Around 200,000 years ago, the last survivors of the species were confined to an oasis on the edge of what is now the Kalahari desert. And yet, Homo sapiens squeaked through, saved by a period of warming that turned much of the surface of the planet into rich grassland, teeming with game. The author begins the last chapter of this hugely enjoyable page-turner by paraphrasing Tolstoy: ‘All happy, thriving species are the same. Each species facing extinction does so in its own way.’ This chapter contemplates the future – a future that will, of course, not include Homo sapiens. We have already incurred a massive ‘extinction debt’ by damaging our own habitat; our population is likely to start falling by around 2100; and our genetic variation is woefully insufficient. We’ll be gone within the next ‘few thousand to tens of thousands of years’, but life will go on, with more ice ages, more extinctions, until eventually, in maybe a billion years, the story of life on Earth will be over. Viewed in the kind of vertiginous perspectives Gee opens up, our human presence looks vanishingly insignificant. And yet we have huge significance as the first and only species to be aware of itself. We owe it to ourselves, and to our fellow species, to conserve what we have, to make the best of our brief existence. ‘Do not despair,’ the author concludes. ‘The Earth abides, and life is living yet.’