The Ghosts of Evolution
Connie Barlow
Basic Books
Nonfiction, Prehistoric Life/Nature/Science
Themes: Plants, Prehistoric Animals
***+
Description
In ages past, the world was a vastly different place. Giant ground sloths and mammoths roamed the Americas. Immense flightless birds roamed New Zealand. These megafauna may have vanished, but their ghosts remain, in plants that still grow mammoth-sized fruits or sprout in moa-deterring thickets, unaware that their partners of millions of years aren't returning. From the long, sugar-rich pods of the honey locust to the peculiar Osage orange, from the devil's claw of the American deserts to the stubborn single remaining species of ginkgo - whose carrion-stench fruits may once have lured dinosaurs - the author examines a host of anachronistic plants around the world, and what they can teach us about our planet's past... not to mention their warnings about our increasingly dire, ecologically devastated future.
Review
This book grabbed me with an interesting concept and readily-observed examples of anachronisms: plants which are overbuilt for current conditions, whose fruits fail and rot far more often than today's ill-suited animal distribution system can spread them, who spend large amounts of energy defending against browsers which no longer are in evidence. The author even mentioned my home town when talking about honey locusts, who have persisted and spread mostly through human intervention: their resistance to pollution makes them ideal urban trees. It's easy to forget that more than just animal life has changed in the course of Earth's history; plants, too, have been emerging, evolving, and passing into extinction, if often with far less fanfare. Thirteen thousand years is less than a blink of the eye in evolutionary terms, far too little time for the Osage orange to re-evaluate a fruit that is too big for extant native gullets in its habitat or the Kentucky coffee tree to consider courting modern seed distributors. Barlow's vision of extinct megafauna serving those purposes is compelling and convincing - as is the warning of what will happen to our wildlands in the future, with increasing rates of animal extinction directly affecting the habitats where they lived. The book, however, tends to meander, wading through many scientific names (not to mention many names of scientists) and competing research papers that failed to interest me as an armchair observer. The section on different animal digestive processes - foregut versus hindgut, and what it means in terms of diet and seed distribution - glazed my eyes terribly. It builds to talk of plans to "rewild" the planet, more specifically the American continents, which suffered perhaps the worst ecological devastation after the last ice age with the loss of native horses and camels (who both evolved here before spreading to their current homes), not to mention the mammoths - which some would suggest "replacing" with elephants. Even if humans could be convinced to sacrifice so much land for such a long-term experiment of minimal personal profit, I do have to wonder if modern species of megafauna, particularly elephants, are sufficient proxies for lost mammoths and mastodons to "restore" the New World to "original" conditions. (This also presupposes that there is a magic "original" condition to be returned to; humans may be today's most significant and detrimental factor in environmental diversity, but other factors were, and are, at work, constantly reshaping the land. Just fencing off a given area and throwing nonnative species that seem "close enough" to what used to live there tens of thousands of years ago - especially when the West has enough trouble re-establishing recently extinct species like wolves and condors - and expecting things to return to "normal" seems more like a fanciful dream than a realistic goal... but, I digress.) Ultimately, while this is a thought-provoking book, I wound up clipping it a half-star for the scientific name overload and a sense of repetition in the middle bits.