The Late Pleistocene Site of Equi (Massa, Apuane Alps): Revaluation of Historical Data and New Discoveries
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DOTTORATO DI RICERCA IN Scienze della Terra CICLO XXVII COORDINATORE Prof. L. Rook The Late Pleistocene site of Equi (Massa, Apuane Alps): revaluation of historical data and new discoveries. Morphological comparison of Italian and European Felids Il sito del Pleistocene superiore di Equi (Massa, Alpi Apuane): rivalutazione dei dati storici e nuove scoperte. Comparazione morfologica dei felidi italiani ed europei Settore Scientifico Disciplinare GEO/01 Dottorando Tutore Dott. Ghezzo Elena Prof. Rook Lorenzo _______________________________ ____________________________________ Coordinatore Prof. Rook Lorenzo ____________________________________ Anno 2012/2014 levan di terra al ciel nostr'intellecto Il Canzoniere, Canto X Francesco Petrarca (1304-1374) 1. Contents 1. Contents 1. Contents 1 2. Introduction 5 2.1. Purposes of the study 5 2.2. Organization of the text 7 2.3. Pleistocene and the large carnivore assemblage of MIS3 9 3. Materials and Methods 13 3.1. Materials 13 3.2. Comparative materials 16 3.3. Methods 18 - Recording of paleontological data 18 - Georeferenting of European sites 21 - Tools for the dimensional and morphological analysis 22 - Abbreviation 23 4. The Late Pleistocene site of Equi 25 4.1. Early studies 25 4.2. New research 31 4.3. Stratigraphical analysis of De Stefani’s historical collection 33 - Metods 38 - Results 41 - Discussion 45 5. Carnivorans from Equi 49 5.1. The faunal guild 49 5.2. Family Felidae Fischer Von Waldheim, 1817 52 1 Ghezzo E. - The Late Pleistocene site of Equi (Massa, Apuane Alps) 5.2.1. The remarkable Panthera Pardus (Felidae, Mammalia) record: taphonomy, morphology, and paleoecology 55 - Anatomical description 56 - Taphonomy 73 - Bites 79 - Sex determination 80 - Body size 83 - Cubs 95 5.3. Family Canidae G. Fischer de Waldheim, 1817 99 5.3.1. Cuon alpinus (Pallas, 1811) (Mammalia, Carnivora): anatomical analysis and palaeoethological contextualisation 105 - Anatomical description 105 - The dhole within the carnivore guild 118 - Concluding remarks 120 6. Focused studies on Felids 123 6.1. Critical overview about cranial variability of European and African lions ( Panthera leo ) 125 - Different scholars for the European lion 127 - General overview 130 - Cranial description 134 - Results 135 6.2. Lynx remains from the Pleistocene of Valdemino Cave (Savona, Northwestern Italy), and the best preserved occurrence of Lynx spelaeus (Carnivora, Felidae) 142 - The Valdemino Cave 144 - Taphonomical remarks 147 2 1. Contents - Description 147 - Lynx spelaeaus (Boule, 1919) 147 - Lynx sp. 151 - Discussion 152 - Evolutionary implications 155 7. Summary and Conclusions 159 8. References 169 9. Appendix 205 10. About the author 227 10.1. Future research 232 11. Acknowledgments 235 3 Ghezzo E. - The Late Pleistocene site of Equi (Massa, Apuane Alps) 4 2. Introduction 2. Introduction 2.1. Purposes of the study This study focuses on the morphological and systematic description of the outstanding historical collection from the Late Pleistocene site of Equi, Apuane Alps (northwestern Tuscany). Historical collections usually do not preserve information about the stratigraphical context, thus lack basic information for understanding and decoding the significance of a particular site or faunal association. Today, many collections represent just a proof of the richness of the sites, but data on bones distribution within the deposit is unknown, and the represented species result as a mixture from different layers, preventing the interpretation of many aspects of the record (from taphonomy, to palaeoecology, to climatic changes, etc.). The very large collection dug out from the Equi site in the 1910s by De Stefani represents a great exception, and in this study we reevaluate, with new interpretations and discoveries, the careful and “modern” professional work of De Stefani and his team. The main part of the study concerns the leopards from Equi, for its exquisite amount of specimens, both from young and adult individuals and for the general paleontological debate about its presence in caves and its role as bone accumulator. The other determined carnivores from Equi are not considered in detail within this study, with the exception of the dhole, a member of the family Canidae which sporadically appears in Italy and Europe and even more rarely is described for its postcranial bones. As a fortunate excetion, dhole is found in the De Stefani collection from Equi with several cranial and postcranial remains, and their features deserved a deeper analysis. Finally, additional studies have been performed on lion and lynx from other Italian Middle to Late Pleistocene sites, taking into account their scarce frequency at Equi. 5 Ghezzo E. - The Late Pleistocene site of Equi (Massa, Apuane Alps) The modern knowledge about morphology, taxonomic position and the evolution of the family Felidae in Europe are sufficiently advanced for the last half million of years (from mid Middle Pleistocene up to the Holocene), with the general presence of large lions as top predator, and leopard, small lynx, and wild cats as subordinate species. In this thesis, I also analyze the paleoecological relationships among these large carnivores in order to clarify their behaviour in the cold climatic conditions of the MIS3. 6 2. Introduction 2.2. Organization of the text This study is divided into four main parts. The first one is a general introduction on the paleontological context, the fossils used for comparisons and the methodology. The second (and main) part focuses on Equi and its exceptional finds, while the third one concerns more specifically on concurrent studies brought out during the elaboration of this thesis. Finally, a conclusive chapter underlines and resumes the main results. In the introduction, the Italian Middle and Late Pleistocene is summarily presented (Chapter 2.3). In Materials and Methods (Chapter 3) are described the sites and fossils used for my comparative analysis. The main stock of studied material comes from Equi, which represent the core of this manuscript. Few other remains from Middle and Late Pleistocene European sites were evaluated, and compared to fossil and modern osteological collections (Chapter 3.1, 3.2). The fossils were analyzed using a traditional comparative method (morphologically and dimensionally), and each find was measured, recorded and described. The huge amount of information recoded was reorganized in a standard matrix- database explained in Chapter 3.3 and also using software for distributional analysis, which allows a graphical return of the paleontological information and intra and inter-site analysis. I took advantage from the possibility to retrieve the geographical coordinates of the sites, georeferencing the data. Chapters 4 and 5 focus on Equi and the fossil record form historical excavation (De Stefani’s collection, excavated in 1910-1917). I described the historical investigation before (Chapter 4.1) and after 1996 (Chapter 4.2). In order to allow an objective and continuative comparison between the historical and modern investigations, I set a link between the osteological labels (which accompany each fossil) and the exhaustive publication published by De Stefani in 1917. Chapter 4.3 explain in detail approach and results. The stratigraphic 7 Ghezzo E. - The Late Pleistocene site of Equi (Massa, Apuane Alps) relocation of the fossils allowed reconsidering also the whole faunal association from Equi, and in Chapter 5.1 are briefly described the carnivorans dug out from the site (in fact, about the entire collection is composed by such kind of animals), focusing the attention on the two main species: the leopards (Chapter 5.2.1) and the dhole (Chapter 5.3.1), which represents exceptional and exciting discoveries in the European paleontological panorama. Chapter 6 is entirely devoted to collateral studies, about the taxonomical position of the European lion (Chapter 6.1.1) and the exquisite preservation of lynx remains from the Middle and Late Pleistocene site of Valdemino Cave (Chapter 6.1.2). Finally, the conclusions (Chapter 7) summarize the different analyses about the main species of Italian felids, evaluating the progresses of the knowledge and new interpretations and perspectives pointed out along these three years of study. Chapter 9 shows the matrixes and table of my database (with the catalog and measurements) and Chapter 10 briefly describe the author and proposes for future paleontological researches about the exciting faunal guild from Equi. Finally, acknowledgments are reported in the Chapter 11, even though one paragraph will never be enough for express all my gratitude. 8 2. Introduction 2.3. Pleistocene and the large carnivore assemblage of MIS3 The term Pleistocene was proposed by Charles Lyell in 1839 and is characterized by the presence of modern fauna, quite similar to the extant species. It includes a time range from 2,588 My up to 11,7 ky ago. The Plio-Pleistocene boundary was related to the first climatic deterioration, determined for the appearance of typical “cold-water neighbours” such as Arctica islandica and Hyalinea baltica at the end of the Neogene. The GSSP for the beginning of Pleistocene was nailed down at Monte San Nicola (Sicily, Italy) (Gibbard, 2004; Pillars and Gibbard, 2012). The Pleistocene is usually divided into three subdivision, used for the first time in 1930s with a chronological significance of Early, Middle and Late Pleistocene (Masini and Sala, 2007). The Early-Middle boundary was placed at the Brunhes-Matuyama paleomagnetic reversal epoch (781 ky) while the Middle-Late boundary is not yet identified, but it is generally recognised with the Eemian Stage from the 2 nd INQUA Congress in 1932 and in 1996 it was posed in a little younger time, at the base of the Marine Isotope Stage 5 (at about 129 ky) (Gibbard, 2004; Pillars and Gibbard, 2012). Mammal paleontologists divide each subepochs of the Pleistocene following the composition of faunal association (Small and Large Mammal Ages). In this thesis I refer to Italian chronology and use Villafranchian, Galerian and Aurelian Ages according to the biochronological unit determined by Azzaroli et al. (1982, 1988), Gliozzi et al. (1997), and Rook and Martínez-Navarro (2010).