This is something conservation biologists have instinctively known for years. But a paper published in the Proceedings of the National Academies of Sciences today offers the strongest evidence yet. After forty years of study, a team of ecologists has concluded that Los Tuxtlas, a famous reserve located in the northernmost tropical forest in the Americas, is experiencing severe ecological deterioration. It’s not that we’re harming the forest per se—it’s what we’re doing in the land around it. And unless we take action, these bastions of diversity could become as biologically impoverished as the land we’ve impacted directly.

“The forest is still there, but it’s moving toward a kind of zombie state.”