Biochronology of Spanish Quaternary Small Vertebrate Faunas
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Quaternary International 212 (2010) 109–119 Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Biochronology of Spanish Quaternary small vertebrate faunas Gloria Cuenca-Besco´ s a,*, Juan Rofes a, Juan Manuel Lo´ pez-Garcı´a b, Hugues-Alexandre Blain b, Roger J. De Marfa´ c, Maria A. Galindo-Pellicena d, M. Lluc Benna´sar-Serra b, Marı´a Melero-Rubio a, Juan Luis Arsuaga d, Jose´ Marı´a Bermu´ dez de Castro e, Eudald Carbonell b a Paleontologı´a, Aragosaurus-IUCA, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna, 12, E-50009 Zaragoza, Spain b Institut de Paleoecologia Humana i Evolucio´ Social (CSIC associated unit), A`rea de Prehisto`ria de la Universitat Rovira i Virgili, Plaça Imperial Tarraco 1, E-43005 Tarragona, Spain c Departament d’Estratigrafı´a, Paleontologı´a i Geocie`ncies Marines, Facultat de Geologia, Universitat de Barcelona, C/Martı´ Franques s/n, 08028 Barcelona, Spain d Centro Mixto de Investigacio´n (UCM-ISCIII) de Evolucio´n y Comportamiento Humanos, c/Sinesio Delgado, 4 (Pabello´n 14), E-28029 Madrid, Spain e Centro Nacional de Investigacio´n sobre la Evolucio´n Humana, Avenida de la Paz 28, E-09004 Burgos, Spain article info abstract Article history: Thousands of fossils of small vertebrates are recorded in one of the most complete stratigraphic sequences Available online 21 June 2009 of the continental European Pleistocene, in the Sierra de Atapuerca. This sequence, with a few interrup- tions, spans the last 1.5 million years. The stratigraphic series is recorded in six karstic cavities in the Sierra de Atapuerca. From the oldest record to the most modern one, these are the Sima del Elefante, Gran Dolina, Galerı´a–Zarpazos, Sima de los Huesos, El Portalo´ n and El Mirador. The faunal successions of continental microvertebrates have made it possible to divide the Atapuerca sequence into 7 faunal units (Atapuerca Faunal Units, ATA FUs), which are based on the first and last local appearances of taxa (LO, HO). The Spanish Quaternary small vertebrate faunas are grouped into 5 distinct biozones, from the oldest to the most recent: Allophaiomys pliocaenicus, Allophaiomys lavocati, Allophaiomys chalinei, Iberomys brecciensis and Iberomys cabrerae. These are calibrated with radiometric and palaeomagnetic dating, allowing the proposal of a continental biochronological scale for the Pleistocene of the Iberian Peninsula. Ó 2009 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction with reference localities in Europe (Cuenca-Besco´ s et al., 1997,1999, 2001; Cuenca-Besco´ s and Garcı´a, 2007; Blain et al., 2008, 2009; The Pleistocene is a time span that represents important faunal Lo´ pez-Garcı´a, 2008). On the basis of the small vertebrate succession turnovers in western Europe (here and in the rest of the text the in the Sierra de Atapuerca cave-infill sites and other localities in lower Pleistocene boundary is applied without considering the Spain, the biochronology of the Early to the Late Pleistocene faunal Gelasian). However, knowledge of the evolution of these faunas and events, is proposed, including the scenario in which humans the biostratigraphy of the continental Pleistocene has in general evolved. Here and in the text that follows, the chronostratigraphical faced the problem of being based on isolated sites and on short and correlations are taken from Kretzoi (1956, 1969), Fejfar and Hein- mostly discontinuous sequences that tend to have a poor small- rich (1990), Markova (1998), Sardella et al. (1998), Tesakov (1998), mammal record. Exceptions include the long stratigraphic Koenigswald and Heinrich (1999), Kowalski (2001), Gibbard and sequences at Kozarnika Cave in Bulgaria (Popov and Marinska, Kolfschoten (2004), Gibbard and Markova (2007), Gliozzi et al. 2007), Ka¨rlich in Germany (Kolfschoten and Turner, 1996) and, for (1997), Masini and Sala (2007), Sala and Masini (2007), and Maul the first part of the Early Pleistocene, the Zu´ jar section in Spain et al. (2007). Biostratigraphic terms follow the synthesis proposed (Agustı´ et al., 2001). The continuous Pleistocene sedimentary by Woodburne (2006). record in the Sierra de Atapuerca caves, with its abundant During the 2007 excavation campaign, new human fossils were mammalian fossil record, offers the possibility of recognizing extracted from Sima del Elefante, from a level (in TELRU TE9) bio- faunal replacements, dating their numerical age, establishing stratigraphically dated to roughly 1.3 Ma (Cuenca-Besco´ s and Rofes, a stratigraphic range of faunal associations and correlating them 2004; Rofes and Cuenca-Besco´ s, 2006), a dating subsequently confirmed by radiometric methods (Carbonell et al., 2008). These human fossils have been provisionally attributed to Homo ante- cessor, thus broadening the temporal range of this new hominin * Corresponding author. Fax: þ34 976761106. species of hominid from 0.8–0.9 Ma (Cuenca-Besco´ s and Garcı´a, E-mail address: [email protected] (G. Cuenca-Besco´ s). 2007) to 0.8–1.3 Ma (this work). 1040-6182/$ – see front matter Ó 2009 Elsevier Ltd and INQUA. All rights reserved. doi:10.1016/j.quaint.2009.06.007 110 G. Cuenca-Besco´s et al. / Quaternary International 212 (2010) 109–119 2. The Atapuerca sites The palaeoanthropological sites of Atapuerca, located near the city of Burgos on St James’s Way in northern Spain (Fig. 1), contain the world’s most extraordinary accumulation of Pleistocene fossil humans and related stone artefacts (e.g., Arsuaga et al., 1993, 1999a,b; Carbonell et al., 1995, 1999; Bermu´ dez de Castro et al., 1997, 2004). In particular, the infilled karstic cave site, the Sima del Elefante (TE) Lower Red Unit (TE-LRU), has yielded the oldest direct evidence of hominins in western Europe, dating from 1.5 to 1.3 Ma (Carbonell et al., 2008). In the Gran Dolina (TD) cave, more than a hundred hominin remains have so far been recovered from the Aurora stratum within lithostratigraphic unit TD 6, around 1.5 m below the Brunhes–Matuyama (B–M) geomagnetic boundary (Berger et al., 2008; Bermu´ dez de Castro et al., 2008). The Atapuerca sites are part of a complex karst system known as the Sierra de Atapuerca. The Sierra de Atapuerca is a minute Mesozoic-core hill, connected to the Iberian Range. It is located 14 km east of Burgos (Fig. 1). The Sierra constitutes a fossil relief barely emphasized in the middle of the Neogene sediments of the Bureba Corridor which connects the Ebro and Duero Basins (Mediterranean and Atlantic realms). For a detailed geomorphological study, see Benito (2004). This small and apparently insignificant hill is of the utmost importance to the faunal migrations between the Mediterranean and the Atlantic. Even today, Burgos is a landmark on St James’s Way. The Sierra de Atapuerca has three main cave systems (Fig. 2). From east to west these are El Mirador, Cueva Mayor and Trinchera del Ferrocarril. The first has provided one of the best Holocene sequences in the Iberian Peninsula (Verge´s et al., 2002). The second comprises the sites of Sima de los Huesos, Galerı´a del Sı´lex, Galerı´a Baja–Sima del Elefante (Sima del Elefante is exposed at the railway trench, and is thus one of the ‘‘Railway’’ or Trinchera localities), Galerı´a del Silo, Galerı´a de las Estatuas and El Portalo´ n. The fossils of Sima de los Huesos represent one of the most important collections of fossil human remains from the Middle Pleistocene (Arsuaga et al., 1997; Martı´nez et al., 2004; Bischoff et al., 2007). The El Portalo´ n sequence includes the end of the Upper Pleistocene and much of the Holocene (Lo´ pez-Garcı´a, 2008). The third, Trinchera del Ferrocarril, is an ancient railway cutting that exposed several fossiliferous beds as well as fossil caves, including the sites of Gran Fig. 1. Map showing the geographic situation of the Sierra de Atapuerca sites (Burgos, Spain). Dolina, Trinchera Penal and Zarpazos–Galerı´a–Tres Simas (Fig. 2). The sequences of Gran Dolina and Sima del Elefante have the oldest hominin record in Europe (Carbonell et al., 1995, 2008; Bermu´ dez de Castro et al., 1997). The Galerı´a–Zarpazos system has provided lithic industry (Cuenca-Besco´ s et al., 1995, 1997, 1999, 2001, 2005; human remains from the Middle Pleistocene that allow these levels Blain et al., 2008, 2009; Rofes and Cuenca-Besco´ s, 2009a,b). to be correlated with those of Sima de los Huesos (Arsuaga et al., The specimens were obtained by concentrating the sediment 1999a,b). The conspicuous red cave sediments from the railway after a process of washing and sieving the sedimentary material trench have long attracted the attention of archaeologists. Never- that had been extracted during the excavation, which took place in theless, it was not until the 1960s that the enterprise of archaeo- yearly campaigns between 1991 and 2007 (roughly 25 tonnes of logical studies was initiated by Clark, Straus and Apella´niz (Ortega, sediment in each campaign). The product was a concentrate con- 1999). The first work in the palaeontology of the Sierra was done by sisting fundamentally of fossil remains of small vertebrates. This Torres in 1976, consisting of an investigation into the fossil Ursidae was duly labelled with an abbreviation indicating the site and from Spain (Torres, 1988). Emiliano Aguirre set the Atapuerca stratigraphic level from which it came, the excavation grid unit, the Project in motion in 1978 (Aguirre, 1995). depth (Z, in metres above sea-level), and the year in which the remains were recovered (e.g. TD 6/H-18/Z: 993,6–993,7/ATA 96), maintaining rigorous stratigraphic control throughout. The 3. Material and methods continuous stratigraphic revision over the course of the excavations made it necessary to fuse or separate some of the classic levels, as in Since the early 1990s, the current Atapuerca team has been the case of TD 3 and TD 4, which are now considered a single carrying out excavations, in various phases, in all the stratigraphic stratigraphic level, TD 3–4 (Pare´ s and Pe´ rez-Gonza´ lez, 1999).