phys.org /news/2025-02-daisyworld-highlights-quick-environmental-shifts.html <https://phys.org/news/2025-02-daisyworld-highlights-quick-environmental-shifts.html> Daisyworld model highlights how quick environmental shifts can doom ecosystems American Institute of Physics 18/02/2025 ------------------------------ [image: Rapid environmental change can threaten even a peaceful Daisyworld] Daisyworld is a basic planet filled with two kinds of daisies that together regulate the temperature to maintain ideal conditions. If the planet heats up or cools down too quickly, all the daisies will go extinct, even if they would otherwise have been able to survive just fine under those conditions. This discovery mirrors similar observations found in other models and observed in real-life ecosystems. Credit: Hannah Daniel/AIP
Imagine a world filled only with daisies. Light-colored daisies reflect sunlight, cooling down the planet, while darker daisies absorb sunlight, warming it up. Together, these two types of daisies work to regulate the planet's temperature, making the world more habitable for all of them. And yet, even in this flowery paradise, a simple change can cause the entire ecosystem to collapse. In *Chaos*, researchers from the University of Cambridge and University College Cork found that this simple daisy-filled ecological model was vulnerable to collapse after experiencing relatively small, but rapid, changes to the environment. The hypothetical planet full of daisies is more than an idle curiosity. It has a name—Daisyworld—and was invented in the 1980s as a model to help scientists understand how organisms could help regulate their environment. Since then, researchers have used it to explore topics like biodiversity and climate change <https://phys.org/tags/climate+change/>. "The Daisyworld model is a classic thought experiment regarding the co-evolution of life and the environment and has been widely used in the teaching of Earth system science," said author Constantin Arnscheidt. Because of its basic and fundamental nature, the authors wanted to use it to study the idea of ecological tipping points, points of no return beyond which an ecosystem is doomed to collapse. This can occur if the environment gets too extreme, but it can also happen if the environment changes too fast. This second type of tipping point is what they were interested in. "Essentially, if you push the system quickly enough, you can trigger a collapse even if you don't push it that hard," said Arnscheidt. "This is called rate-induced tipping: The rate of change is the key factor in determining whether the system tips." Using mathematical modeling, the authors discovered that rate-induced tipping can happen even in Daisyworld. If the planet heats up or cools down too quickly, all the daisies will go extinct, even if they would otherwise have been able to survive just fine under those conditions. This discovery mirrors similar observations found in other models and observed in real-life ecosystems <https://phys.org/tags/ecosystems/>. "Rate-induced tipping has been shown to be relevant in more and more systems, especially complex ones like those in Earth science and ecology," said Arnscheidt. "It's also a phenomenon that will likely be quite relevant for humanity as we continue to navigate an era marked by rapid human-driven rates of change." Understanding rate-induced tipping is crucial because these collapse conditions are less obvious, but just as deadly. Without a clear picture of how these ecosystems respond to rapid environmental changes, we could unwittingly doom far more than a planet of hypothetical daisies. "The fact that we can find rate-induced tipping in a model as classic and well-studied as Daisyworld, more than four decades since its inception, suggests that rate-induced tipping might be present in many other classic models if we only look for it," said Arnscheidt. *More information:* Rate-induced biosphere collapse in the Daisyworld model, *Chaos: An Interdisciplinary Journal of Nonlinear Science* (2025). DOI: 10.1063/5.0240983 <https://dx.doi.org/10.1063/5.0240983> *Abstract* There is much interest in the phenomenon of rate-induced tipping, where a system changes abruptly when forcings change faster than some critical rate. Here, we demonstrate and analyze rate-induced tipping in the classic “Daisyworld” model. The Daisyworld model considers a hypothetical planet inhabited only by two species of daisies with different reflectivities and is notable because the daisies lead to an emergent “regulation” of the planet’s temperature. The model serves as a useful thought experiment regarding the co-evolution of life and the global environment and has been widely used in the teaching of Earth system science. We show that sufficiently fast changes in insolation (i.e., incoming sunlight) can cause life on Daisyworld to go extinct, even if life could in principle survive at any fixed insolation value among those encountered. Mathematically, this occurs due to the fact that the solution of the forced (nonautonomous) system crosses the stable manifold of a saddle point for the frozen (autonomous) system. The new discovery of rate-induced tipping in such a classic, simple, and well-studied model provides further supporting evidence that rate-induced tipping—and indeed, rate-induced collapse—may be common in a wide range of systems. ------------------------------ -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/geoengineering/CAHodn99LS0x4zm4PA5jG-7ANbAUzxyQVyWo98vTGWs8VRjgWrQ%40mail.gmail.com.
