Human activity has reduced biodiversity across nearly all ecosystems on Earth, according to a global analysis of more than 2,000 studies.
Phoebe Weston reports for The Guardian.
In short:
- A synthesis of 2,000 global studies found that human activity reduced species richness by about 20% in areas with high human impact.
- The five key drivers of biodiversity loss are habitat change, direct exploitation, climate change, invasive species, and pollution, with agriculture playing an outsized role.
- Researchers saw the strongest losses among reptiles, amphibians, and mammals, and noted that even when species counts stay steady, ecosystems are losing functional diversity.
Key quote:
“Our findings show that all five factors have a strong impact on biodiversity worldwide, in all groups of organisms and in all ecosystems.”
— François Keck, study lead author and postdoctoral researcher at the Swiss Federal Institute of Aquatic Science and Technology
Why this matters:
From the quality of the food on our plates to the water flowing through our taps, the intricate web of life that supports human health and stability is unraveling. As forests are razed for monoculture crops and wetlands drained for development, we’re not just displacing species — we're making ecosystems far less resilient.
These shifts aren’t always dramatic or immediate; often, they’re slow, almost invisible changes, such as fewer pollinators in a farm field or diminished fungal diversity in a forest floor. But the consequences are significant. Without biodiversity, systems that purify air and water, regulate climate, and ward off disease begin to falter. Scientists are increasingly warning that we are trading rich, adaptive ecosystems for stripped-down versions that are more vulnerable to shocks — from pandemics to extreme weather. The result is a kind of ecological hollowing-out that’s difficult to reverse and dangerous to ignore.
Read more: Human activity is pushing ecosystems toward collapse, experts warn
