Ecosystems Aren’t Speeding Up With Climate Change—They’re Slowing Down, Study Finds
A new analysis of a century of biodiversity data reveals a surprising trend: despite accelerating global warming, the rate at which species are replaced in ecosystems is actually decreasing, a sign researchers say points to a worrying level of environmental degradation.
A team from Queen Mary University of London (QMUL) published their findings in Nature Communications, challenging the long-held assumption that rising temperatures and shifting climates would inevitably lead to a faster reshuffling of ecological communities. The research analyzed a massive database of biodiversity surveys encompassing marine, freshwater, and terrestrial environments.
“Many ecologists hypothesise that as global warming accelerates, change in nature must speed up,” explained Dr. Emmanuel Nwankwo, lead author of the study. “But we found this engine is now grinding to a halt.”
The ‘Multiple Attractors’ Phase
The study focused on species turnover rates – the speed at which species replace each other – from before and after the 1970s, a period marked by a documented surge in global surface temperatures. Contrary to expectations, the data showed a significant slowdown in turnover rates over 1-5 year periods, consistent across diverse environments from bird communities to the seabed.
“We were surprised how strong the effect is,” said Professor Axel Rossberg, a co-author at QMUL. “Turnover rates typically declined by one third.”
Researchers attribute this counterintuitive finding to the way ecosystems are fundamentally organized. They suggest that the analyzed communities aren’t simply reacting to external climate forces, but are instead operating within a state known as the “Multiple Attractors” phase. This concept, initially proposed by theoretical physicist Guy Bunin in 2017, describes a state where species continuously replace one another through internal interactions – akin to a complex game of “rock-paper-scissors” – even without external environmental changes. The QMUL study provides strong empirical evidence supporting the existence and dominance of this phase in nature.
Degradation and Diminishing Species Pools
However, the slowdown in turnover isn’t a sign of ecosystem health. The authors argue it’s a consequence of environmental degradation and the shrinking of regional species pools. In a thriving “Multiple Attractors” ecosystem, a large pool of potential colonizers fuels the continuous cycle of species turnover. As human activity degrades habitats and reduces these pools, the number of potential replacements dwindles, slowing the pace of change.
“In other research we are seeing clear indications that human impacts cause the slowing of turnover,” Dr. Nwankwo stated. “It is worrying.”
The findings underscore a critical point: a lack of visible change in local species composition should not be equated with stability or health. Instead, the widespread slowdown may signal that the internal engines of biodiversity are losing momentum due to the depletion of regional life. This suggests that ecosystems, rather than adapting rapidly to climate change, are becoming increasingly stagnant, a potentially dangerous sign for long-term resilience.
