Unraveling ecosystems: A new mathematical framework reveals the architecture of biotic interactions.
An interdisciplinary team has developed an innovative approach that integrates multiple types of biotic interactions into a single framework, allowing a deeper understanding of how these relationships affect biodiversity and ecosystem functioning.
An international team of researchers, including scientists from the Institute of Interdisciplinary Physics and Complex Systems (IFISC, CSIC-UIB) and the Institut Mediterrani d'Estudis Avançats (IMEDEA, CSIC-UIB), has developed an innovative mathematical framework that integrates various types of interactions between different species of plants, animals and fungi, providing a deeper and more complete view of the complexity of ecosystems.
A multi-layered approach to study species interactions
Until now, most studies on ecological complexity have focused on specific interactions between species that mediate a single ecological function, such as pollination or herbivory. This perspective has overlooked the fundamental role that species play in simultaneously participating in multiple ecological functions. This new approach overcomes this limitation by integrating multiple types of species interactions into a single model, allowing for a more comprehensive analysis of functional patterns and their relationship to biodiversity and ecosystem resilience.
Imagen: Balearis lizzard visiting flowers at Na Redona. Author: Toni Escandell
Species and ecological functions: Key to maintaining ecosystem balance.
The study introduces a multi-layered approach, which integrates different species interaction networks, providing a deeper understanding of how multifunctionality impacts the ecosystem. To test this model, more than 1500 interactions between 691 plant, animal and fungal species were analyzed on the islet of Na Redona in the Balearic Islands, a small island community that, due to its relative simplicity and isolation, offers an ideal setting to test this innovative methodological framework These species were involved in six ecological functions: pollination, herbivory, seed dispersal, decomposition, nutrient uptake and fungal pathogenicity. “Comparing a plant species pollinated by two animals to one that interacts with dozens of fungi is not always straightforward. However, by quantifying the likelihood of these interactions, we can make more accurate comparisons between a plant's pollination and its saprophytic interactions. This ability to compare was fundamental for the next steps in our research,” says Sandra Hervías-Parejo, IMEDEA researcher and author of the paper.
The study reveals that interactions do not occur randomly, but are organized in a structured way. In addition, both species and key functions, such as woody plants and fungal decomposition, were identified as essential for maintaining the balance of the ecosystem. The disappearance of these species could cause a significant impact on the extinction of other organisms by triggering species extinction cascades. “A provocative idea emerging from our research is the exploration of species-function duality. We propose to consider ecological functions not only as connectors between species, but also as elements that are themselves subject to evolution and extinction,” reveal Mar Cuevas-Blanco and Lucas Lacasa, IFISC researchers and authors of the study.
Applications beyond ecology
What is innovative about this framework is that it is not only limited to ecological networks, but can be extended to other complex systems. For example, it can be applied to genetics to understand how genes interact to generate phenotypes or to the economic domain, to study how goods are traded between countries in different economic sectors.
This dual approach, from the perspectives of species and functions, opens new possibilities for quantifying the complexity of ecosystems and better understanding the influence of multifunctionality on their functioning and biodiversity.
In future research, it is proposed to apply this model to diverse environments and examine their spatial and temporal dynamics. This will provide a more holistic and in-depth view of ecosystems, thus providing a more effective guide for conservation efforts in the face of stressors such as climate change and for mitigating biodiversity loss.
Reference
Hervías-Parejo, S., Cuevas-Blanco, M., Lacasa, L., Traveset, A., Donoso, I., Heleno, R., Nogales, M., Rodríguez-Echeverría, S., Melián, C.J., & Eguíluz, V.M. (2024). On the structure of species-function participation in multilayer ecological networks. Nature Communications,https://www.nature.com/articles/s41467-024-53001-1