Judging by the title of this book, you might expect it to talk of 25 remarkable kinds of rocks and minerals. But in the preface, geologist and palaeontologist Donald R. Prothero makes clear that his book looks as much at famous outcrops and geological phenomena. Bringing together 25 readable and short chapters, he gives a wide-ranging tour through the history of geology, celebrating the many researchers who contributed to this discipline.
Mammoths and sabertooth cats are but two icons of an assemblage of large animals, or megafauna, that disappeared between roughly 50,000 to 12,000 years ago. As with all mass extinctions, several explanations have been put forward, but one man and his idea take centre stage in these discussions: Paul S. Martin’s overkill hypothesis. In End of the Megafauna, palaeomammalogist Ross D.E. MacPhee carefully scrutinises this idea, weighs up the arguments for and against, and explains its enduring allure. To quote Huxley, is this another example of “the slaying of a beautiful hypothesis by an ugly fact”?
The story of human evolution is constantly being refined with new findings and there is a glut of accessible books that cover this topic from various angles. Yet, with The Cradle of Humanity, geography professor Mark Maslin manages to provide an interesting and novel take on the subject, showing the reader how a happy combination of larger factors conspired to influence and steer our evolutionary trajectory. It could have ended up so differently…
What has plate tectonics ever done for us? Not having studied geology, I have a basic understanding of the movement of earth’s continents, but this book made me appreciate just how much of current geology it underpins. Marine geophysicist Roy Livermore, who retired from the British Antarctic Survey in 2006 after a 20-year career, convincingly shows here that the discovery and acceptance of plate tectonics was a turning point in geology, on par with Darwin’s formulation of evolution by natural selection. To paraphrase evolutionary biologist Theodosius Dobzhansky: nothing in geology makes sense except in the light of plate tectonics.
Before plate tectonics became an accepted idea in geology, Lyell’s doctrine of uniformitarianism still ruled supreme (see my review of Cataclysms: A New Geology for the Twenty-First Century for a short introduction). A corollary was that the continents supposedly had always been where they are now. One observation scholars had to explain away was that the same fossils occur on both sides of the various oceans. Looking at maps, some people noticed the thin strip of land connecting North and South America and concluded that land bridges must have formed and sunk beneath the waves at just the right times in history to enable migrations (see Four Revolutions in the Earth Sciences: From Heresy to Truth for more details). As explained in The Tectonic Plates are Moving!, we know better nowadays. Nevertheless, the concept of land bridges is still alive and well today, and palaeobotanist Alan Graham here introduces five of them, exploring their effects on biogeography, climate, and human history.