When a species enters unfamiliar land, the balance of that land is shaken. We call this sentence to mind in front of names like the red-eared slider or the bur cucumber. But what happens if we change the subject of the sentence to humans? Pat Shipman's 『Invasive Species Human』 (Prunsoop, 2017) starts from that question.
What the book deals with is the ecological history of the human species. While we spread out into new continents and climate zones, what happened to the species that had long lived there? The author does not drive this question toward moral accusation. She examines it as a general phenomenon that appears when one species enters an ecosystem.
The effect of this perspective is large. There is no good or evil in the term invasive species. It is only an ecological description that when a species enters an environment without natural predators and rapidly takes over resources, the species around it are pushed out. The moment that description is applied to humans, what is happening now begins to read as the extension of an old pattern rather than a sudden accident.
This is why a publication covering climate and biodiversity takes up this book in summer. We count the rise in heatwave days and the fragmentation of habitats as problems that came after the Industrial Revolution. But the point at which humans gained the power to change the composition of ecosystems goes back much further. The task of carbon neutrality also shows its true size when placed on that long time axis.
The book's strength lies in the breadth of its view. The author's touch in handling fossils, bones, and the evidence of paleoecology is firm, and she weaves the spread of humanity into a single continuous process rather than a set of regional events. Where popular books on climate change mostly focus on the last 200 years, this book takes tens of thousands of years as its basic unit.
There are also places where the account grows thin. Discussions dealing with causation in prehistory inherently allow a wide range of interpretation, and this book's account chooses one leading explanation within that range. If a reader accepts the conclusions as settled fact, the book's virtues are diminished instead. Since it is a book about the distant past, there is little to grasp if one seeks today's policies or technological solutions.
So this book suits readers who want to widen their questions more than readers looking for answers. Someone who looks at carbon reduction targets and recycling rates every day and grows curious about where those numbers came from, someone who looks at the graphs in a biodiversity report and asks again why now of all times. It is a book published in 2017, but it becomes clearer when read now.
This book suits someone who looks at carbon reduction targets and recycling rates every day and grows curious about where those numbers came from. Because following a record measured in tens of thousands of years reveals that today's crisis was not a sudden event.
The account that something decreased everywhere our species passed also leaves room to be read in reverse. If it is a species with the power to reduce, the power to increase lies in the same hands.
