In peril? A view of Earth taken from the moon by the astronauts aboard Apollo 11.
In peril? A view of Earth taken from the moon by the astronauts aboard Apollo 11.NASA

The ambitious new idea of “Half Earth” — sparing 50 percent of the planet for Nature — may be attractive as scientists warn of climate change and mass extinctions in the future. But a team of researchers from the University of Cambridge says the idea would affect more than 1 billion people.

The researchers found that 247 million people already live inside areas that would be protected, while another 760 million would find themselves in protected areas, if the “Half Earth” plan were implemented, the university said in a statement.

The team called for proponents of the plan “to recognize and take seriously” the human consequences of their proposals.


“In light of continuing global biodiversity loss, one ambitious proposal has gained considerable traction amongst conservationists: the goal to protect half the Earth. Our analysis suggests that at least one billion people live in places that would be protected if the Half Earth proposal were implemented within all ecoregions,” said the abstract of the study, which was published Monday in the journal Nature Sustainability.

“Taking into account the social and economic impacts of such proposals is central to addressing social and environmental justice concerns, and assessing their acceptability and feasibility,” the study said.

E.O. Wilson, the prominent Harvard emeritus professor known for his work on sociobiology, the study of the genetic basis of social behavior of animals, including humans, popularized the idea of a “Half Earth” in a 2016 book, “Half-Earth: Our Planet’s Fight for Life,” researchers said.

Wilson argued that year in a Sierra Club magazine article, “Only by committing half of the planet’s surface to nature can we hope to save the immensity of life-forms that compose it. Unless humanity learns a great deal more about global biodiversity and moves quickly to protect it, we will soon lose most of the species composing life on Earth.”


Judith Schleicher, lead author, said in the statement, “Living in areas rich in natural habitat can boost mental health and well-being. In some cases, protected areas can provide new jobs and income through ecotourism and sustainable production.”

“However, at the other extreme, certain forms of ‘fortress’ conservation can see people displaced from their ancestral home and denied access to resources they rely on for their survival,” Schleicher said in a statement.

The researchers analyzed global datasets to determine how to provide 50 percent protection for every “ecoregion,” or large distinct habitat area, such as Central African mangrove and Baltic mixed forests.

“Conservation needs strong action to protect life on earth, but this must be done in a way that takes account of people and their needs,” said co-author Chris Sandbrook from Cambridge University’s Department of Geography.

Martin Finucane can be reached at martin.finucane@globe.com