Where do camels belong? You may be surprised to learn that they evolved and lived for tens of millions of years in North America—and also that the leek, national symbol of Wales, was a Roman import to Britain, as were chickens, rabbits and pheasants. These classic examples highlight the issues of “native” and “invasive” species. We have all heard the horror stories of invasives. But do we need to fear invaders?

In this controversial book, Ken Thompson asks: Why do very few introduced species succeed, why do so few of them go on to cause trouble, and what is the real cost of invasions? He discusses, too, whether fear of invasive species could be getting in the way of conserving biodiversity and responding to climate change.

Dr. Ken Thompson was for many years a lecturer in the Department of Animal and Plant Sciences at the University of Sheffield. He now writes and lectures on gardening and ecology. He has written five other books, including Do We Need Pandas? The Uncomfortable Truth about Biodiversity.

Ken Thompson's profile page

"I raced through this engaging book and found, at the end, that my view of the introduced starlings and dandelions in my backyard, not to mention the countless non-native species in the surrounding country, had shifted into a more optimistic space." —Alan de Queiroz, evolutionary biologist and author of The Monkey's Voyage

"Ken Thompson presents a stimulating challenge to our perceptions of nature." —George Monbiot

"This is a well put together book about the science and the philosophy surrounding invasive species." —the Times

"lively and punchy…you walk away from this book feeling flushed and a bit bruised." —the Sunday Times

“The information he presents is compelling . . . This title brings an important minority opinion to light.” —Library Journal

"Thompson makes his case in a lively, readable style, spiced with a healthy dose of sarcasm towards 'aliens = bad' fundamentalists. Better yet, he bolsters his argument with plenty of citations from the scientific literature, which adds welcome heft." —New Scientist