Researchers make disturbing discovery about missing species in protected habitats

Wildlife refuges and national parks are meant to protect nature, but new research suggests that these areas might not be as intact as they seem.

A global team of scientists uncovered a hidden form of biodiversity loss inside the most remote and protected places. As two of the researchers from Macquarie University detailed in an article for The Conversation, it's called "dark diversity," and it refers to native plant species that are missing from habitats where they should be thriving.

What's happening?

In one of the largest studies of its kind, published last month in the journal Nature, more than 200 scientists surveyed nearly 5,500 sites across 119 regions worldwide. They didn't just count what was growing; they looked for what was missing. Using environmental data, they identified native plant species that should be able to grow in a given area but weren't found there.

Even in protected areas with little visible human interference, only about one-third of potential native plants were present. In more developed regions, that figure dropped to 20%.

The disappearance of the missing plants was strongly linked to human activity, including roads, croplands, urban infrastructure, and pollution. These activities can fragment habitats, eliminate seed dispersers, and cut off ecological recovery. Over time, even untouched-looking landscapes become less capable of supporting the variety of life they once held.

Why does this matter?

The disappearance of native plants is a warning sign that vital natural systems are breaking down. Fewer plant species can lead to fewer pollinators, which puts pressure on our food systems. Water filtration, soil stability, and even disease regulation can be disrupted when plant communities are weakened.

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For communities living near or relying on these ecosystems — whether for farming, clean water, cultural practices, or climate protection — this kind of loss reduces resilience. It makes it harder to recover from climate shocks such as wildfires and floods. It also complicates efforts to restore landscapes that protect homes, support economies, and ensure future food security.

If these missing species aren't accounted for, conservation work may fall short, protecting what's left rather than restoring what's needed.

What can be done about it?

There's hope in the data. The study found that the areas where at least a third of the landscape remained relatively undisturbed tended to retain more plant species. These areas offer a model for how land management can support both nature and people.

Now that researchers can pinpoint which species are missing from particular areas, there's an opportunity to bring them back. By reintroducing key plants and rebuilding the relationships they support — including with pollinators, soil organisms, and seed-spreading wildlife — communities can strengthen food production, climate protection, and more.