Hélène Morlon, Director of Research at the CNRS and team leader at the Institut de Biologie de l'Ecole Normale Supérieure, will be giving a seminar on Monday 10 March 2025 from 12h30 à 13h30 in the Salle Egée at the MIO, on the theme : The build-up of species diversity: from terrestrial macro-organisms to eukaryotic plankton drifting along oceanic currents.
Abstract The marine eukaryotic plankton is extremely diverse, with a diversity that varies across oceans, yet the processes underlying this diversity are poorly understood. Present-day biological diversity resulting from past speciation and extinction events, I will present models of diversification that, when applied to the phylogenies of extant and potentially also extinct (fossil) species, allow us to make inferences about these historical events. While most applications will concern terrestrial macro-organisms, I will illustrate their application to the marine eukaryotic plankton with results on diatoms diversification. Next, I will ask the enigmatic question of how new species are formed in an environment globally connected by currents over short time scales. Based on results comparing the biogeographies and diversities of the 70 most diverse groups of eukaryotic plankton, I will formulate hypotheses on the relative role of current-mediated dispersal constraints versus environmental selection in the speciation process, and discuss promising avenues for testing these hypotheses.
Biography : Dr. Hélène Morlon is a CNRS research director at the Institut de Biologie de l'ENS in Paris. After an initial training in mathematics, she did a master and PhD in ecology & evolution in France. As a post-doc in the US, she worked on microbial biogeography, the modeling of biogeographic patterns, and the development and application of phylogenetic diversification models. She joined the CNRS in 2010. Her team at IBENS focuses on understanding the fundamental processes that generate and maintain biodiversity.
The seminar will also be monitored by Zoom.
Meeting ID: 923 5511 1254
Secret code: 615822
