Understanding processes at the origin of species flocks with a focus on the marine Antarctic fauna

• Published in: Biological Reviews
• Main Authors: Chenuil, Anne, Saucède, Thomas, Hemery, Lenaïg G., Eléaume, Marc, Feral, Jean-Pierre, Améziane, Nadia, David, Bruno, Lecointre, Guillaume, Havermans, Charlotte
• Other Authors: Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement IRD : UMR237-Centre National de la Recherche Scientifique (CNRS), Biogéosciences UMR 6282 (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN), Bremen Marine Ecology (BreMarE), University of Bremen, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung = Alfred Wegener Institute for Polar and Marine Research = Institut Alfred-Wegener pour la recherche polaire et marine (AWI), Helmholtz-Gemeinschaft = Helmholtz Association, Royal Belgian Institute of Natural Sciences (RBINS), The IPEV programs REVOLTA (#1124) and PROTEKER (#1044), the Australian Antarctic Division (CEAMARC cruise) and the SCAR (International Polar Year CEAMAR IPY#53 , CAML, and current SCAR SRPs AntEco and AnT-ERA), the Belgian Science Policy Office (contract nr BR/132/A1/vERSO) and the German Science Foundation (DFG, project HA7627/1-1)., ANR-07-BLAN-0213,ANTFLOCKS,ANTARCTIC SHELF AS A SPECIES FLOCKS GENERATOR(2007)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: competition; ecological niche; diversification; endemicity; extinction; life-history trait; phylogeny; adaptive radiation; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDV.BID]Life Sciences [q-bio]/Biodiversity; Antarctic; Antarc*
• Online Access: https://hal.science/hal-01688786; https://hal.science/hal-01688786/document; https://hal.science/hal-01688786/file/2018_Chenuil_Biological%20Reviews_pr_Understanding%20processes%20at%20the%20origin%20of%20species%20flocks%20with%20a%20focus%20on%20the%20marine%20Antractic%20fauna.pdf; https://doi.org/10.1111/brv.12354

24 pages International audience Species flocks (SFs) fascinate evolutionary biologists who wonder whether such striking diversification can be driven by normal evolutionary processes. Multiple definitions of SFs have hindered the study of their origins. Previous studies identified a monophyletic taxon as a SF if it displays high speciosity in an area in which it is endemic (criterion 1), high ecological diversity among species (criterion 2), and if it dominates the habitat in terms of biomass (criterion 3); we used these criteria in our analyses. Our starting hypothesis is that normal evolutionary processes may provide a sufficient explanation for most SFs. We thus clearly separate each criterion and identify which biological (intrinsic) and environmental (extrinsic) traits are most favourable to their realization. The first part focuses on evolutionary processes. We highlight that some popular putative causes of SFs, such as key innovations or ecological speciation, are neither necessary nor sufficient to fulfill some or all of the three criteria. Initial differentiation mechanisms are diverse and difficult to identify a posteriori because a primary differentiation of one type (genetic, ecological or geographical) often promotes other types of differentiation. Furthermore, the criteria are not independent: positive feedbacks between speciosity and ecological diversity among species are expected whatever the initial cause of differentiation, and ecological diversity should enhance habitat dominance at the clade level. We then identify intrinsic and extrinsic factors that favour each criterion. Low dispersal emerges as a convincing driver of speciosity. Except for a genomic architecture favouring ecological speciation, for which assessment is difficult, high effective population sizes are the single intrinsic factor that directly enhances speciosity, ecological diversity and habitat dominance. No extrinsic factor appeared to enhance all criteria simultaneously but a combination of factors (insularity, ...