http://www.sciencemag.org/news/2019/09/wilderness-areas-halve-risk-extinction-plants-and-animals

It may seem like an obvious argument: Undeveloped lands, including parks, wilderness areas, and national forests, are critical refuges for endangered or threatened species. But scientists have had surprisingly little evidence to support that claim, aside from the occasional anecdote.

Now, a new study suggests that if present global habitat-degradation trends continue, vascular plants and invertebrates living in wildlands—from wildflowers to bees—are twice as likely to survive as their cousins dwelling in nonwilderness areas.

To come up with the new figure, researchers first divided Earth’s land surface into millions of 1-kilometer square grids. Not counting Antarctica, protected or unprotected de facto wildernesses made up about 20%. The rest were lands that had been more heavily affected by human activities, ranging from farming and ranching to mining, logging, and urban development. The researchers then filled in the known ranges of 400,000 species of plants and invertebrates—and estimated the extinction risk for each one.