Protecting The World’s Green Equilibria

Guest Author: Christopher Wills

Few experiences in life are as overwhelming as a walk through a virgin rainforest, or a swim through an untouched coral reef. Here is a vivid glimpse of such a moment, captured on a visit to the island of New Britain, part of Papua New Guinea.


On this coral reef, which is typical of the rich ecosystems of southeast Asia’s coral triangle, teeming schools of Anthia and Dascyllus fish hover over clusters of staghorn coral.

Green EquilibriaIn my recent book “Green Equilibrium: The Vital Balance of Humans and Nature(Oxford, 2013), I take the reader to many such diverse ecosystems. We visit virtually untouched rainforests and reefs that give us a glimpse into billions of years of evolutionary history. But we also encounter other places that have been badly damaged by human activity, and still others where scientists and conservationists are working hard to restore their ecological diversity.

On the way we discover why some ecosystems are more resistant to human-caused damage than others.  We also discover that these ecosystems have had profound effects on the humans who live in them. The genes and behaviors of peoples as varied as the tribes of the New Guinea highlands, the inhabitants of Nepal’s swampy and fever-ridden Terai, and the Sherpas and Tibetans who have adapted to life at extreme altitude, have all been molded by the worlds in which they live. We are much more intimately connected to, and influenced by, the natural world around us than most of us realize.

Divergence among the cultures of these New Guinea tribes people has been encouraged by the country’s rugged terrain, which has led to language barriers and warfare over limited resources.

imageWe explore the many ways in which ecosystem diversity, and the human diversity that often accompanies it, are generated. Some common themes emerge. One such mechanism, which my collaborators and I have discovered to be operating in rainforests around the world, is a type of natural selection called frequency-dependent selection. We found that rare species of tree often have an advantage. The advantage disappears when the species become common.

When such selection operates over long periods of time, it can generate and maintain diversity in ecosystems — a phenomenon that can lead to the complex ecological balances that I call green equilibria.

Such mechanisms have also increased the genetic diversity of the gene pools of all the species that inhabit ecosystems — including our own species. And they have opened up an opportunity for us to undo the damage we have done to our planet, and to harness and repair its delicate balances. At the end of the book, we explore how our own rich genetic heritage has endowed our species as a whole with a wealth of capabilities that far exceed those of any individual. And we see how it is possible to harness these genetic resources to save, and to restore, the delicate web of our planet’s green equilibria.

About Author:

Christopher Wills image


Christopher Wills is Professor of Biological Sciences Emeritus at the University of Calilfornia San Diego. The author of many popular books on evolution and biology, he was given the AAAS Award for Public Understanding of Science and Technology in 1999. His most recent books include The Darwinian Tourist (2010) and Green Equilibrium (2013), both from Oxford University Press.




Leave a Reply

Stay Connected