ISLANDS IN DEEP TIME

Ancient Landscapes Lost and Found By Markes E Johnson

Columbia University Press

■ Geologist Markes E Johnson believes that humans inhabit two different worlds. There’s the present, ecological world, made tangible by things such as fauna and flora, and then there’s the geological record, best thought of in the context of millions or even billions of years.

In his new book, Islands in Deep Time, Johnson recounts expeditions across the globe to a dozen ancient ‘palaeoislands’ – ‘miniature worlds with discreet ecologies’ caught in varying passages of geological time. Understanding how such islands appeared under different climatic and environmental conditions during different geological eras offers us a window into the distant past that could help foretell the distant future.

The book is replete with topographic maps illustrating the islands’ physical structure, together with a global map highlighting their geographical locations ‘unique to that time’, as well as images of Johnson’s fossil finds. Energetic anecdotes throughout the travelogue-type book help to colour otherwise quite technical chapters. He poses questions such as, ‘How does life first arrive on fresh island shores?’ and what factors allow some marine species to traverse deep oceans, ‘hopping from one island to another largely unchanged’ while stopping others short. The author’s palpable intrigue with ‘geoheritage’ helps to bring a human element to the page, with Johnson often drawing a spiritual connection to nature. But there are also a multitude of specialist terms in what’s a rather niche book that could be jarring for a generalist reader. Geologists and palaeontologists, Johnson writes, can play a vital role in understanding how the ‘natural mood swings of our planet’ occurred long before humans were around. ‘If we can better understand the physical conditions that contributed to those swings,’ he writes, ‘we can at least make a better prediction as to what lies ahead due to global warming.’