Functional redundancy is gaining increasing attention in ecological studies as a critical element of biodiversity, potentially linked to ecosystems’ capacity to withstand environmental disturbances. While acknowledging that the conceptual and quantitative aspects of functional redundancy can be challenging, we aim to clarify various facets of this intriguing discussion. Our goal is to demonstrate that functional redundancy extends beyond functional similarity and can represent a fundamental dimension of biodiversity.
Similarity alone is not a sufficient indicator of stability, and both similarity and species diversity need to be accounted for to estimate redundancy. Furthermore, the potential for insurance mechanisms grows when species possess similar effect traits but differ in sensitivity to perturbations. Paradoxically, a crucial aspect of functional redundancy lies in the “uniqueness” of species. Ecosystem stability is likely maximized when species, similar in some traits, exhibit dissimilarity in others.
In addition, asynchrony in the temporal fluctuations of species has a significant impact on stability. Species with similar functions (effect traits) can replace each other following environmental fluctuations due to their different response traits, supporting redundancy effects.
Embracing redundancy proves beneficial, aligning with the idea that maximizing species diversity enhances stability. Redundancy should be viewed as a promoter of safety in ecosystems, a concept that deserves reinforcement for broader audiences.