Climatic evolution in Western Europe during the Cenozoic: insights from historical collections using leaf physiognomy

Abstract

A major climatic shift, from a glasshouse world to a colder climate with well-developed ice sheets, occurred during the Cenozoic. Such a transition is recorded in both marine and terrestrial records. The latter is more fragmentary and thus comparatively less well known from a climatic point of view. Leaves are abundant fossil remains, which can be used as terrestrial climatic proxies. In this study, several historical collections from France and Belgium were re-investigated. We applied the Climate Leaf Analysis Multivariate Program in order to document the regional past climate from middle Paleocene to middle Miocene in Western Europe. Our analysis suggest relatively cooler conditions during middle Paleocene, followed by a gradual increase of mean annual temperature and precipitation seasonality during late Paleocene; increased temperature seasonality rather than a global cooling at the Eocene-Oligocene transition; an increase of temperature between early and late Oligocene and warm temperate climate in Western Europe similar to other parts of Europe during middle Miocene. These results are broadly consistent with the global trends observed through the Cenozoic era in the marine record. This study provides new quantitative paleoclimatic estimates for various key periods of the Cenozoic era in Western Europe. The consistency of our results with previous studies based on multiples proxies is in favor of the use of historical collections to reconstruct past climates, as long as sufficient sampling is provided. RÉSUMÉ Évolution du climat en Europe occidentale durant le Cénozoïque : apports des collections historiques à travers l'utilisation de la morphologie foliaire. Durant le Cénozoïque, une transition majeure d'un climat chaud et humide vers un climat plus froid avec des calottes glaciaires bien développées, est observée. Cette transition est documentée dans les registres fossiles marin et continental. En raison de la nature plus fragmentaire de ce dernier, les conditions climatiques continentales sont comparativement moins bien connues. Parmi les restes de plantes conservées dans les sédiments, les feuilles sont particulièrement abondantes et peuvent être utilisées comme proxy climatique terrestre. Dans cette étude, plusieurs collections historiques de France et de Belgique ont été réétudiées. La méthode Climate Leaf Analysis Multivariate Program a été appliquée, afin de documenter le climat régional du Paléocène moyen au Miocène moyen en Europe occidentale. Notre analyse suggère des conditions climatiques relativement fraîches pendant le Paléocène moyen, suivies d'une augmentation graduelle de la MAT et de la saisonnalité des précipitations au cours du Paléocène supérieur, une saisonnalité accrue plutôt qu'une baisse de la MAT à la transition Eocène-Oligocène, une augmentation des températures au cours de l'Oligocène et un climat tempéré chaud semblable au reste de l'Europe durant le Miocène moyen. Dans l'ensemble, ces résultats sont cohérents avec les tendances globales observées au cours du Cénozoïque dans le ...

From Toad to Frog, a CT-based Reconsideration of Bufo servatus , an Eocene Anuran mummy from Quercy (France)

“…At the end of the Eocene, a major cooling is recorded during the Eocene-Oligocene transition (EOT). This cooling is well recorded in numerous studies using different proxies (Escarguel et al, 2008;Héran et al, 2010;Lunt et al, 2017;Tanrattana et al, 2020) and is linked to the establishment of permanent ice caps on the Antarctica continent (Vandenberghe et al, 2012;Boscolo Galazzo et al, 2014). In Europe, the climate and environments dramatically changed.…”

“…We confirm the African affinities of T. servatus, proposed almost a decade earlier (Laloy et al, 2013), and we link this taxon to the faunistic exchange from Africa to Europe (Rage, 1984b;Gheerbrant and Rage, 2006) during the Palaeocene-Eocene thermal maximum (PETM) (Sluijs et al, 2006), possibly in latter half of this event, in the Early Eocene Climatic optimum (EECO). Starting in the Late Paleocene (Tanrattana et al, 2020), the temperature increased (Sluijs et al, 2006;Bohaty et al, 2009) in Western Europe, and remained warm until the end of the Middle Eocene (Bohaty et al, 2009). During this period, Western Europe was characterized by a subtropical climate, with evergreen forest under warm and humid conditions (Escarguel et al, 2008;Héran et al, 2010;Tanrattana et al, 2020).…”

“…Starting in the Late Paleocene (Tanrattana et al, 2020), the temperature increased (Sluijs et al, 2006;Bohaty et al, 2009) in Western Europe, and remained warm until the end of the Middle Eocene (Bohaty et al, 2009). During this period, Western Europe was characterized by a subtropical climate, with evergreen forest under warm and humid conditions (Escarguel et al, 2008;Héran et al, 2010;Tanrattana et al, 2020). During this period, a wave of new vertebrate taxa is recorded (Gheerbrant and Rage, 2006) Rage, 2003).…”

“…In Europe, the climate and environments dramatically changed. The climate became drier, with stronger seasonality and the appearance of a dry season (Escarguel et al, 2008;Tanrattana et al, 2020). The vegetation cover changed from forests to woodland savannah (Escarguel et al, 2008).…”

Reconstructing leaf area from fragments: testing three methods using a fossil paleogene species

“…According to this second hypothesis, increased leaf size might be consistent with a moderate cooling. Alternatively, a strengthening of temperature seasonality (i.e., mean annual range of temperatures), with colder winters, has been documented in Europe from the late‐middle Eocene to the early Oligocene (e.g., Mosbrugger et al, 2005; Eldrett et al, 2009; Hren et al, 2013; Tanrattana et al, 2020). Among different temperature metrics, leaf size seems particularly correlated to temperature of the growing season (Wright et al, 2017).…”