Initially, Giovanni Strona started doing research as a bachelor student in fish parasitology, focusing, in particular, on the taxonomy of small, highly host specific flatworm parasites named Monogenea. From then, during his master thesis and afterwards during the PhD at the University of Milan-Bicocca, in Italy, Strona has progressively expanded his interests towards more general ecological questions.
“However, my original interest for host-parasite interactions left a strong mark on my future research, which has always kept an eye on the importance of, and the mechanisms regulating, interspecific interactions. This emerges, in particular, on my activities dealing with ecological networks and the fundamental role these play in the ongoing biodiversity crisis and global extinction processes,” Strona says.
Macroecology – and a soft spot for marine ecology
Strona is currently working on various open issues in macro-ecology, mostly related to the idea that we cannot completely understand how natural systems are responding and will respond to global change without embracing the complexity of the often elusive, direct and undirect ecological links underlying communities.
“My research is quite broad, involving different systems and tackling different questions, even if I have a soft spot for marine ecosystems and I am leading/involved in several projects on coral reef ecology”, says Strona.
The main common goal of Strona’s projects and activities is that of improving our understanding of the mechanisms which permit ecological systems to become complex, and how these mechanisms, and hence the persistence of natural communities, are challenged by global change.
For example, in a very recent project Strona has been exploring the effect of remoteness/isolation on the structure of ecological networks, looking at the question both from a theoretical perspective, and applied to a real-world system (reef fish-coral interactions at the global scale). The main finding there, is that ecological networks tend to become more fragile towards global change hazards, e.g. ocean warming and acidification, as remoteness - distance from human settlements - increases.
“This counteracts the expectation of a negative relationship between the extinction risk experienced by natural communities with distance from humans, i.e. the intuitive idea that communities far away from direct human impacts, such as pollution, habitat destruction and overharvesting, are safer than communities close to humans, and hence, from a conservation perspective, obvious strongholds for biodiversity,” Strona explains.
In a different ongoing project in collaboration with Professor Corey Bradshaw (Flinders University, Australia), Strona has simulated realistic “virtual” Earths populated by natural communities - modelling both diversity, species interactions, dispersal, adaptation and extinctions. These have been placed under different future scenarios of climate and land use change to investigate future patterns (decline) of vertebrate diversity at the global scale accounting. For the first time, this simulation provide deep ecological insights not only on species’ specific responses to global change, but also on complex community and metacommunity extinction mechanisms mediated by species interactions.
Ecological interactions in the spotlight
Strona’s research show that not accounting for the importance of ecological interactions can result in a severe underestimation of the magnitude of the ongoing mass extinction event. In a proof-of-concept paper published in 2018 (https://doi.org/10.1038/s41598-018-35068-1) Strona quantified the underestimation to be more than order of magnitude. In the same research Strona identified global warming as the worst possible scenario for biodiversity.
“Our current research is now giving more substance to those estimates, and is unravelling several important extinction mechanisms that might serve not only to predict future trends and, in a constructive perspective, inform conservation management, but also to better understand past extinctions”, explains Strona.
Motivation from moving fast forward
According to Strona, one obvious aspect, which makes his work exciting right now, is the unprecedented, and still growing, free access to large datasets of ecological and environmental information, paired to exceptional computational power (see for example the resources provided for free to researchers by the Finnish CSC, https://www.csc.fi/), as well as the rapid developments of powerful statistical techniques (especially in the field of Artificial Intelligence).
“Thinking, more specifically, to network science and ecological interactions, things are moving fast. In particular, the progresses made by physicists are continuously generating knowledge and tools with a high potential relevance for ecology. The field of ‘multilayer’ networks, permitting to explore the structure and dynamics of multiple networks connected in space, time or by ecological processes, appears as one of the next frontiers in ecological research”, Strona says.
“I also think that there is still much to be said about the hidden (“higher order”) interactions (such as competition) which permeate ecological systems in addition to the more obvious, direct pairwise links connecting resource to consumers. My general feeling is that we now have all we need to find convincing answers to fundamental questions that have been around for decades. Although this does not mean it will be an easy task, the sheer possibility is a great source of enthusiasm and inspiration”.
Thriving Nature program enables fundamental questions
“I think that the Thriving Nature program will give me not only time and freedom to focus on fundamental questions, but also a great research environment and many chances for fruitful collaborations. The broadness of interests covered by Thriving Nature research groups is so wide that the main risk I will foresee is that of being frustrated by having too many opportunities to setup exciting collaborative projects, and have to choose between them,” Strona summarises.