What image does an island bring to mind? When I hear the word island, I get a feeling of solitude and defiance. I imagine a lone figure battling silently against all the wild attacks thrown from all four sides. Islands in Deep Times is a book written by geologist Markes E. Johnson that tries to demystify paleoislands for the layperson. I received an advance copy of the book from its publisher, Columbia University Press, through Netgalley in exchange for feedback.
A few months ago, I got a chance to travel back in time by reading a book titled The Universal Timekeepers, which described the science behind using isotopes of elements for precise dating of objects and events. This book takes you through a similar experience, where you progressively travel through time by exploring paleoislands, their shorelines, and the biological fossils found in them. Paleoislands are landscapes that preserve information on the geography and ecology of the past. By studying their coastlines, we are able to arrive at conclusions about the environment of the earth and the continental structure in the past.
The writer takes us to twelve islands of different sizes and located in different parts of the earth, on which the keys to understanding the past are preserved. The journey begins at Mount Monadnock, located in New Hampshire, about which Ralph Waldo Emerson has written a poem titled Monadnoc. Monadnoc isn't an island in the conventional sense because it is not surrounded by water. But there was a time when it was.
Right now it is a sky island, and monadnock is the name that is used to identify such sky islands all over the world. Wind and waves erode the banks of the islands over time, and an ecosystem develops according to the force of the natural forces. By studying the erosion that these coastlines have undergone and the kinds of fossils available, it is possible to decipher the properties of these ecosystems.
We are then taken to more such islands in deep time, all over the world, and progressively exposed to different eras in the past in which the ecosystem existed. The wearout of the rocks helps us reconstruct the continental structures of those periods. From the Baraboo archipelago in Wisconsin, which dates back to the Cambrian period (around 500 million years ago), to the Cape Verde and Seychelles archipelagos that date back to Pleistocene times (125000 years ago), we are able to witness the evolution of continental plates and the biology of the present states through these pages.
Islands in Deep Time is an interesting book if you love to learn more about nature and its evolution. I loved the detailed explanation with which the writer elaborated his findings. The book follows the style of a travelogue, and we are made to participate in the excursion that he and his team underwent in these regions. Wherever the description took a difficult technical turn, accompanying maps, photos, and pictures helped a lot. I was especially fascinated with the several photos of fossils, which made me marvel at the long periods, spanning millions of years, when earth had only invertebrate life form or when all the present continents were combined together and several permutations and combinations they underwent to reach the present state.
The book ends with a chapter dedicated to the sacredness of islands and the need to preserve these immense storehouses of knowledge and wisdom from the deep past. It makes you connect more with nature and realise that we are just very minor players in the history of our planet.