Generic Indicators for Loss of Resilience Before a Tipping Point Leading to Population Collapse

Abstract

Theory predicts that the approach of catastrophic thresholds in natural systems (e.g., ecosystems, the climate) may result in an increasingly slow recovery from small perturbations, a phenomenon called critical slowing down. We used replicate laboratory populations of the budding yeast Saccharomyces cerevisiae for direct observation of critical slowing down before population collapse. We mapped the bifurcation diagram experimentally and found that the populations became more vulnerable to disturbance closer to the tipping point. Fluctuations of population density increased in size and duration near the tipping point, in agreement with the theory. Our results suggest that indicators of critical slowing down can provide advance warning of catastrophic thresholds and loss of resilience in a variety of dynamical systems.

Biodiversity and Resilience of Ecosystem Functions

“…current climate, land use, habitat 52 quality). This ignores the need to ensure that essential ecosystem functions will be provided 53 under a range of environmental perturbations that could occur in the near future (i.e. the 54 provision of resilient ecosystem functions).…”

“…However, because models are parameterised and validated (where undertaken) on the current set of environmental conditions they are often only suitable for producing indicators of short-term ecosystem function flows rather than resilience under environmental perturbations (Figure 4). Attempts at developing resilience indicators for ecological functions have been limited mostly to 'early warning systems' [53,92]. These focus on emergent properties of systems that might precede impending critical state transitions, e.g.…”

“…These focus on emergent properties of systems that might precede impending critical state transitions, e.g. 'critical slowing down' [53]. However, these properties only occur before critical transitions in a subset of cases and thus are likely to be poor general predictive indicators of resilience [91].…”

Cooperators trade off ecological resilience and evolutionary stability in public goods games

“…(b) The stability to freeloader invasion is plotted against the ecological resilience for increasing investment. (c) An optimal fixed strategy for a particular environment (death rate d ¼ 0.5) becomes sub-optimal as the environment changes, increasing the death rate, and it eventually leads to population collapse (experimental observation of this was reported in [13]). For all plots: r [26] that this function has a unique root (for r .…”

Mammalian conservation: scientific frontiers and socio-political pitfalls

“…Can we someday predict if and when they will occur? Dai et al (2012) and Fung et al (2013) suggest possible methods for this. Sometimes there may be the loss of a keystone or dominant species from the community that forces major reorganization.…”