Summary
The Messinian Salinity Crisis was the most extreme paleoenvironmental perturbation that has ever taken place in the Mediterranean. Approximately 7 million years ago, the straits connecting the Mediterranean Sea to the Atlantic Ocean started to restrict, and by 5.5 million years they closed. High-amplitude fluctuations in both temperature and salinity gave place to a hypersaline isolated Mediterranean, where marine organisms struggled to survive. In our recently published studies, we assembled and revised the marine fossil record from before and after the crisis to quantify the crisis's effect on the Mediterranean's biodiversity. We documented for the first time a clear perturbation of the biota even during the restriction phase, as well as a high degree of reorganisation of the marine ecosystem after the crisis, with most of the change in the taxonomic composition attributed to species turnover. Only a handful of endemic Mediterranean species may have survived the crisis. Furthermore, the present-day NW-to-SE decreasing gradient in species richness first appeared after the Messinian salinity crisis, suggesting that neither the distance from the Atlantic source nor the temperature gradient are the causes of the gradient today. Finally, we propose a model for the disruption in marine functional connectivity patterns, which is associated with forming a large evaporitic basin. This model can now be tested against the past's diverse ecosystem structures associated with marginal marine basins formed due to the birth and death of the oceans.
Brief biography
I studied at the National and Kapodistrian University of Athens, Greece, where I obtained a 4-yr BSc degree in Geology, and then a MSc in Paleontology and Stratigraphy, and a PhD in Geology and Geoenvironment, with my thesis on Paleoichthyology and paleoenvironmental reconstructions in the Eastern Mediterranean. Afterward I stayed at the same institute, employed as a postdoctoral researcher and lecturer until 2020. I then moved to the University of Vienna in Austria to expand my research, leading my own projects on reconstructing ancient marine food webs and developing biogeochemical proxies. My research targets the interaction between climate, connectivity and marine ecosystems of the past, to provide insights for the present and future. Currently, I am leading the PAGES working group Q-MARE «Disentangling climate and pre-industrial human impacts on marine ecosystems» (2022–2024) and the new COST Action SaltAges «Social, biological and climatic impacts of salt ages» (2024–2028).