Equids from Emine-Bair-Khosar Cave (Crimea, Ukraine): co-occurrence of the stenonid Equus hydruntinus and the caballoid E. ferus latipes based on skull and postcranial remains

Eline N. van Asperen, Krzysztof Stefaniak, Iurii Proskurnyak, and Bogdan Ridush

Plain Language Abstract

Amongst the bones excavated from the cave Emine-Bair-Khosar in the Chatyrdag Massif in the Crimean Mountains, Ukraine, there are about 250 horse remains dating from the last ice age. Analyses of the size and shape of these bones reveal that in this area, a small, ass-like horse occurred alongside a large horse. The fossil assemblage includes several well-preserved skulls, unique finds for the smaller ass species. This horse had a short muzzle, which is thought to be advantageous in a cold climate. The larger horse is characterised by relatively long legs, indicating that the climate and environment in which these animals lived was suitable for horses. There are more fossils of the small horse than of the large horse in this cave. This is as expected from what we know of the behaviour of modern horse species and how behavioural differences between the two horse species would influence their use of the habitats in the region.

Resumen en Español

Équidos de la cueva de Emine-Bair-Khosar (Crimea, Ucrania): concurrencia del estenonoide Equus hydruntinus y el caballoide E. ferus latipesbasada en restos craneales y postcraneales

Las asociaciones faunísticas del Pleistoceno superior procedentes de la cueva de Emine-Bair-Khosar en el macizo de Chatyrdag (Montes de Crimea, Ucrania) contienen unos 250 restos de équidos. Los análisis morfológicos detallados revelan la existencia entre ellos de la especie estenonoide, de pequeño tamaño, Equus hydruntinus junto con una especie caballoide, de mayor tamaño, identificada como Equus ferus latipes. La presencia en la asociación de dos cráneos extraordinariamente bien conservados de Equus hydruntinus es muy significativa y contribuye en gran medida a nuestro conocimiento de esta enigmática especie del Pleistoceno. En este artículo se describen estos cráneos, así como uno de Equus ferus latipes, y se comparan con los de otras especies estrechamente relacionadas. Los cráneos de E. hydruntinus se diferencian de los de otras especies cercanas por su corto hocico, una adaptación a condiciones climáticas frías. Los huesos postcraneales completos de ambas especies también son frecuentes en la asociación, con huesos largos de Equus hydruntinus relativamente robustos y similares a los de otras muestras de E. hydruntinus del Pleistoceno superior. La presencia de una forma de Equus ferus latipes con extremidades largas indica que las condiciones ambientales en las que se acumuló la asociación eran relativamente frías pero favorables a los équidos. Las abundancias relativas de las dos especies en la asociación están de acuerdo con los patrones de uso de los recursos observados en las especies cercanas actuales.

Palabras clave: Equidae; morfología esquelética; Pleistoceno superior; Crimea

Traducción: Miguel Company

Résumé en Français

Les équidés de la grotte Emine-Bair-Khosar (Crimée, Ukraine) : co-occurrence du sténoïd Equus hydruntinus et du caballoïd E. ferus latipes sur la base des restes crâniens et post-crâniens.

Les assemblages fauniques du Pléistocène supérieur extraits de la grotte Emine-Bair-Khosar du massif de Chatyrdag dans les montagnes criméennes, Ukraine, contiennent près de 250 restes d’équidés. Des analyses morphologiques détaillées révèlent l’occurrence de la petite espèce de sténoïd Equus hydruntinus en association avec une grande espèce de caballoïd identifiée comme Equus ferus latipes. La présence dans cet assemblage de deux crânes de Equus hydruntinus extrêmement bien préservés est de grande importance et contribue grandement à notre connaissance de cette espèce énigmatique du Pléistocène. Ces crânes, de même qu’un crâne de Equus ferus latipes, sont décrits ici et comparés à des crânes d’autres espèces proches. Les crânes de E. hydruntinus se distinguent des autres équidés proches par leurs museaux courts, une adaptation aux conditions climatiques froides. Les os post-crâniens complets sont également fréquents dans les échantillonnages pour les deux espèces, avec des os longs relativement robustes pour Equus hydruntinus, similaires à ceux des autres échantillons de E. hydruntinus du Pléistocène supérieur. La présence de formes de membres allongés chez Equus ferus latipes indique que les conditions environnementales sous lesquelles l’assemblage s’est accumulé étaient froides mais favorables aux équidés. L’abondance relative des deux espèces dans l’assemblage est cohérente avec les schémas d’occupation des terres documentés chez leurs parents actuels.

Mots clés : Equidae ; morphologie du squelette ; Pléistocène supérieur ; Crimée

Translator: Olivier Maridet

Deutsche Zusammenfassung

Equiden aus der Emine-Bair-Khosar Höhle (Crimea, Ukraine): das gemeinsame Vorkommen des stenoiden Equus hydruntinus und des caballoiden E. ferus latipes auf der Grundlage von Schädel-und Postcranialelementen

Die spätpleistozänen Faunenassemblagen aus der Emine-Bair-Khosar Höhle im Chatyrdag Massiv der Crimea Berge, Ukraine umfassen rund 250 Equidenreste. Detaillierte morphologische Untersuchungen ergaben, dass die kleine stenoide Art Equus hydruntinus neben der großen caballoiden Art, die als Equus ferus latipes identifiziert wurde, vorkommt. Die Existenz zweier sehr gut erhaltener Schädel von Equus hydruntinus in der Assemblage ist von großer Relevanz und trägt viel zum Wissen über diese rätselhafte pleistozäne Art bei. Diese Schädel werden hier zusammen mit einem Schädel von Equus ferus latipes beschrieben und mit den Schädeln von nah verwandten Arten verglichen. Die Schädel von E. hydruntinus unterscheiden sich von anderen nah verwandten Equiden durch ihre kurzen Schnauzen, eine Adaption an kalte Klimabedingungen. In der Probe kommen auch häufig Postcranialelemente von beiden Arten vor, insbesondere relativ robuste Langknochen von Equus hydruntinus, die ähnlich denen aus anderen spätpleistozänen Proben mit E. hydruntinus sind. Das Vorhandensein einer langbeinigen Art von Equus ferus latipes weist darauf hin, dass die Umweltbedingungen während der die Assemblage angehäuft wurde, relativ kühl waren, jedoch günstig für Equiden. Die relative Häufigkeit der beiden Arten in der Assemblage entspricht den Flächennutzungsmustern die für die heute noch lebenden Verwandten dokumentiert sind.

SCHLÜSSELWÖRTER: Equidae; Skelettmorphologie; Spätes Pleistozän; Crimea

Translator: Eva Gebauer

Arabic

Translator: Ashraf M.T. Elewa

Polski Abstrakt

Koniowate z jaskini Emine-Bair-Khosar (Krym, Ukraina): współwystępowanie konia Equus hydruntinus i zebry E. ferus latipes na podstawie materiału czaszkowego i pozaczaszkowego<

Późnoplejstoceński zespół faunistyczny wydobyty w jaskini Emine-Bair-Khosar usytuowanej w Masywie Chatyrdag w Górach Krymskich na Ukrainie, zawiera około 250 szczątków koniowatych. Szczegółowa analiza morfologiczna ujawniła obecność małego konia z gatunku Equus hydruntinus obok dużej zebry zidentyfikowanej jako Equus ferus latipes. Obecność dwóch bardzo dobrze zachowanych czaszek Equus hydruntinus w danym zespole jest bardzo znacząca i przyczynia się znacznie do zwiększenia naszej wiedzy na temat tego enigmatycznego gatunku plejstoceńskiego. Czaszki te, jak i czaszki Equus ferus latipes, opisujemy oraz porównujemy do czaszek blisko spokrewnionych gatunków. W obrębie koniowatych, czaszki E. hydruntinus wyróżniają się swymi krótkimi pyskami; co jest adaptacją do zimnych warunków klimatycznych. U obu gatunków często obecne są również kompletne kości szkieletu pozaczaszkowego, przy czym stosunkowo solidne kości długie Equus hydruntinus podobne są do kości innych późnoplejstoceńskich okazów E. hydruntinus. Obecność długonogich form Equus ferus latipes wskazuje, iż warunki środowiskowe, w których dany zespół faunistycznego został nagromadzony, były stosunkowo chłodne, ale dla koni korzystne. Względne liczebności obu gatunków w zespole zgodne są z wzorcami wykorzystania terenu udokumentowanymi u dziś żyjących krewnych.

Słowa kluczowe: Equidae; morfologia; późny plejstocen; Krym

Translation: supplied by authors

Riassunto in Italiano

Equidi della Emine-Bair-Khosar Cave (Crimea, Ucraina): compresenza dell’equide stenonide Equus hydruntinus e dell’equide caballoide E. ferus latipes sulla base di resti craniali e postcraniali

Un’associazione faunistica del Pleistocene superiore rinvenuta nella Emine-Bair-Khosar Cave (Massiccio del Chatyrdag, Monti di Crimea, Ucraina) ha restituito circa 250 resti di equidi. Analisi morfologiche di dettaglio rivelano la presenza della specie stenonide di piccola taglia Equus hydruntinus insieme ad una specie di grande taglia, caballoide, identificata come Equus ferus latipes. Molto significativa è la presenza nell’associazione di due crani estremamente ben conservati di Equus hydruntinus, in quanto contribuisce ad una migliore conoscenza di tale enigmatica specie pleistocenica. I suddetti crani, così come un cranio di Equus ferus latipes, sono qui descritti e confrontati con crani di specie ad essi vicine. I crani di E. hydruntinus si distinguono per i loro musi corti, un adattamento a condizioni climatiche fredde. Nel campione sono frequenti anche ossa postcraniali complete di entrambe le specie, con ossa lunghe relativamente robuste appartenenti ad Equus hydruntinus; in questo tali reperti sono simili ad altri, sempre di E. hydruntinus, del Pleistocene superiore. La presenza di una forma di Equus ferus latipes dagli arti allungati indica che le condizioni ambientali in cui l’associazione si è accumulata erano relativamente fredde ma favorevoli agli equidi. L’abbondanza relativa delle due specie nell’associazione è in accordo con il pattern di utilizzo del territorio documentato per le specie viventi ad esse più vicine

Parole chiave: Equidae; morfologia scheletrica; Pleistocene superiore; Crimea

Translator: Chiara Angelone

APPENDIX 1. Full dataset for the equid remains from Emine-Bair-Khosar, recovered during field seasons 1999-2009 (available as Excel spreadsheet).

APPENDIX 2. Measurements on the EBK cranial specimens and mean values for comparative material; Equus hemionus and Equus przewalskii: Eisenmann, 1980; Equus ferus gallicus: Cardoso and Eisenmann, 1989; Equus ferus latipes: Kuzmina, 1997; Equus hydruntinus: Burke et al., 2003.

APPENDIX 3. Mean, minimum, and maximum values for the upper dental elements of the EBK equid specimens and comparative material; L=length, W=width, Lprot=length of the protocone; Equus hemionus: Eisenmann, 1980; Equus hydruntinus (Lunel-Viel): Bonifay, 1991; Equus hydruntinus (Crimea), Equus przewalskii, Equus ferus latipes: Kuzmina, 1997; Equus ferus gallicus: Eisenmann, online data.

APPENDIX 4. Mean, minimum, and maximum values for the lower dental elements of the EBK equid specimens and comparative material; L=length, W=width; Equus hemionus: Eisenmann, 1981; Equus hydruntinus (Lunel-Viel): Bonifay, 1991; Equus hydruntinus (Crimea), Equus przewalskii, Equus ferus latipes: Kuzmina, 1997; Equus ferus gallicus: Eisenmann, online data

APPENDIX 5. Longbone mean, minimum, and maximum values for the EBK specimens and comparative material; Equus hemionus, Equus ferus gallicus and Equus przewalskii: Eisenmann, online data; Equus hydruntinus: Kuzmina, 1997; Equus ferus latipes: Kuzmina, 1997, Eisenmann, 1991.

APPENDIX 6. Mean values for metacarpal measurements of the EBK specimens and comparative material; Equus hemionus, Equus africanus and Equus przewalskii: Eisenmann, 1979; Equus hydruntinus (Crimea) and Equus ferus latipes: Kuzmina, 1997; Equus hydruntinus (Italy): Eisenmann & Bekouche, 1986; Equus hydruntinus (Lunel-Viel): Bonifay, 1991; Equus ferus gallicus: Eisenmann, online data.

APPENDIX 7. Mean values for metatarsal measurements of the EBK specimens and comparative material; measurements according to Eisenmann, 1979; Equus hemionus, Equus africanus and Equus przewalskii: Eisenmann, 1979; Equus hydruntinus (Crimea) and Equus ferus latipes: Kuzmina, 1997; Equus hydruntinus (Italy): Eisenmann & Bekouche, 1986; Equus hydruntinus (Lunel-Viel): Bonifay, 1991; Equus ferus gallicus: Eisenmann, online data.

APPENDIX 8. Mean values for first and third phalanx measurements of the EBK specimens and comparative material; Equus hemionus, Equus asinus and Equus przewalskii: Dive &Eisenmann, 1991; Equus hydruntinus (Crimea) and Equus ferus latipes: Kuzmina, 1997; Equus hydruntinus (Lunel-Viel): Bonifay, 1991; Equus ferus gallicus: Eisenmann, online data.

APPENDIX 9. Scatter plots of measurements on selected dental elements and longbones for the EBK specimens compared with several equid species; 1. M1/2; 2. m1/2; 3. humerus (breadth of the proximal epiphysis plotted against greatest length); 4. tibia (smallest depth of the diaphysis plotted against greatest length).

Eline N. van Asperen
Research Centre in Evolutionary Anthropology and Palaeoecology
School of Natural Sciences and Psychology
Liverpool John Moores University
Liverpool
and
Centre for Anatomical and Human Sciences
Hull York Medical School
University of York, United Kingdom
 
Eline van Asperen earned an MA with distinction in Archaeological Sciences from Leiden University, The Netherlands, where she worked on the faunal material of the Middle Pleistocene site Schöningen 13II-4. She then moved to York, United Kingdom, where she did her PhD in Archaeology, studying the biostratigraphy and ecology of European late Middle Pleistocene horses. She is presently a Marie Curie ERG postdoctoral fellow in the Faculty of Science of Liverpool John Moores University, United Kingdom. Her current research focuses on the interaction of climatic factors and community dynamics in the shaping of the Last Interglacial large mammal fauna of Europe.

Krzysztof Stefaniak
Department of Palaeozoology
Zoological Institute
University of Wrocław
Wrocław, Poland

Krzysztof Stefaniak graduated from Wrocław University, Poland in 1986 and received his PhD in 2001. He has been working at the Department of Palaeozoology, Zoological Institute, University of Wroclaw, Poland since 1984. His interests are focused on fossil mammals, especially mammalian ungulates, including Neogene and Quaternary deer. Further areas of research are archaeozoology, caves and study of fossil DNA in Quaternary mammals from Poland and Ukraine. He has participated and led research (excavation) for 30 years on karst area in Poland and Ukraine. He lectures to students in Palaeontology, Archaeozoology, and Quaternary Studies at the University of Wrocław.

Iurii Proskurnyak
Department of Paleozoology and Paleontological Museum
National Museum of Natural History of the National Academy of Science of Ukraine
Kiev, Ukraine

Iurii Proskurnyak is a biologist and palaeontologist. In 2007 he graduated from the Zoological Department of the Chernivtsi National University, Ukraine, with a Master’s degree in biology. Through his involvement in caving activities he became interested in cave palaeontology. In 2010 he completed postgraduate study in the National Museum of Natural History of the National Academy of Sciences of Ukraine, in the Department of Vertebrate Paleozoology. At present he is a fund custodian in the same institution in the Department of Vertebrate Paleozoology. The subjects of his investigation are in the area of comparative morphology, population biology, palaeozoogeography, systematics and evolution of the ungulates of the Late Pleistocene in the East-European Plain.

Bogdan Ridush
Department of Physical Geography and Natural Management
Chernivtsi "Fedkovych" National University
Chernivtsi, Ukraine

Bogdan Ridush is a geomorphologist, Quaternary geologist and archaeologist. He graduated from the Department of Physical Geography and Geomorphology of University of Chernivtsi, Ukraine in 1983. His special interest since his student years is in karst relief and caves exploration. For many years, he was employed in engineering geology, dealing mainly with Quaternary deposits. Since 1996 he has been involved in cave archaeology and in 2000 he received his Candidate degree (equal to Ph.D. in UIS countries) in this field from the University of Chernivtsi. Since 2000 he has expanded his research into complex investigations of cave deposits as proxies of palaeogeographical signals. Searching for and exploration of palaeontological cave sites in the Ukrainian Carpathians, Podillya, Mountain Crimea and other areas has his special attention.
At present he is an Assistant Professor in the Department of Physical Geography, Chernivtsi National “Fedkovych” University (Ukraine) and Head of Department of Cave Palaeontology and Speleoarcheology in the Ukrainian Institute of Speleology and Karstology (Symferopol).

FIGURE 1. Cross-section through the Emine-Bair-Khosar Cave (Vremir and Ridush, 2005).

FIGURE 2. Terminology used to refer to particular dental traits.

FIGURE 3.1. Skull no. Ba2 384 (photo E. van Asperen; scale in cm). FIGURE 3.2. Skull no. Bc 141 (photo P. Socha; scale in cm). FIGURE 3.3. Skull no. Bm001 (photo E. van Asperen; scale in mm).

FIGURE 4. Log ratio diagram of measurements of the small EBK equid skulls compared with those of Equus hydruntinus.

FIGURE 5.1. Log ratio diagram of measurements of the EBK equid longbones compared with those of extant and extinct equids; hum=humerus, fem=femur, rad=radius, tib=tibia, mc=metacarpus, mt=metatarsus, ph1a=anterior first phalanx, ph1p=posterior first phalanx, ph3=third phalanx; GL=greatest length, GB=greatest breadth. FIGURE 5.2. Log ratio diagram of measurements of the EBK equid longbones compared with those of extant and extinct equids; hum=humerus, rad=radius, fem=femur, tib=tibia; Bp=proximal breadth, SD=smallest breadth of the diaphysis.

FIGURE 6.1. Log ratio diagram of measurements of the small EBK equid metacarpals compared with those of Equus hemionus, several E. hydruntinus samples and E. africanus. FIGURE 6.2. Log ratio diagram of measurements of the small EBK equid metatarsals compared with those of Equus hemionus, several E. hydruntinus samples and E. africanus. FIGURE 6.3. Log ratio diagram of measurements of the EBK equid anterior first phalanges compared with those of Equus hemionus, several E. hydruntinus samples and E. asinus. FIGURE 6.4. Log ratio diagram of measurements of the EBK equid posterior first phalanges compared with those of Equus hemionus, several E. hydruntinus samples and E. asinus.

FIGURE 7. Log ratio diagram of measurements of the large EBK equid skulls compared with those of Equus przewalskii, Equus ferus gallicus and Equus ferus latipes.

FIGURE 8.1. Log ratio diagram of measurements of the large EBK equid metacarpals compared with those of Equus przewalskii, E. ferus latipes and E. ferus gallicus. FIGURE 8.2. Log ratio diagram of measurements of the large EBK equid metatarsals compared with those of Equus przewalskii, E. ferus latipes and E. ferus gallicus.

TABLE 1.Radiocarbon dates (uncalibrated) for bones from various layers at the Ba site in Emine Bair Khosar Cave (Stankovic et al.,2011; A. Nadachowski, K. Stefaniak, and B. Ridush, personal commun. 2011).

TABLE 2.Dental characteristics of different equid lineages (Alimen, 1946; Eisenmann, 1980, 1981, 2010; Eisenmann and Baryshnikov, 1994; Smit 1996; Baxter, 1998; Eisenmann and Mashkour, 1999; Burke et al., 2003; Orlando et al., 2006; Forstén, 1999).