Jelle Reumer & Isabelle Robert Two interesting taphonomical phenomena in remains of Artiodactyla (Mammalia: Cervidae, )

Author’s address: Jelle Reumer, Natuurmuseum Rotterdam, P.O. Box 23452, 3001 KL Rotterdam, the Nether- lands & Faculty of Geosciences, Utrecht University, the Netherlands, [email protected]; Isabelle Robert, Muséum national d’histoire naturelle, Paris, France; present address: Centre Guillaume le Conquérant, 13 bis rue de Nesmond, F.14402 Bayeux, France, [email protected]

Abstract of endemic Candiacervus cretensis from the cave of Mavro Mouri (, Greece) are here identified as having been altered post-mortem by gastric juices of the bearded vulture Gypaetus barbatus. They are not pathological, neither the result of malnutrition, and malnutrition must thus be eliminated as a possible cause of endemic evolution within Candiacervus. Horns of the endemic Myotragus balearicus from Mallorca show peculiar V-shaped endings, which are the result of gnawing by the ruminants themselves. The phenomenon is known from other ruminant taxa and from other places, such as Weichselian Rangifer tarandus from the Netherlands, and is not due to human action. kaupia | Darmstädter Beiträge zur Naturgeschichte | Heft 14 | 53–57 | Heftkaupia Beiträge 14 | Darmstadt, | Darmstädter zur Naturgeschichte 18. Juli 2005 | 53 Fig. 1a: SONDAAR’s (1977) illus- Introduction tration of a sick Cretan metatarsal. Two taphonomical phenomena that appear to be persistently misunderstood are found in the palaeon- tological literature. One is the bizarre condition of a sample of bones that belonged to the endemic deer Candiacervus spp. from the locality of Mavro Mouri (Crete, Greece). Their aberrant charac- ter has been explained as being the result of either malnutrition, of a disease, or of the influence of bor- ing insects. Here we will provide a simple taphono- mical explanation: post-mortem damage to the bones inflicted by bearded vultures (Gypaetus barbatus). The other one is the partial disappearance of the horns of the Pleistocene| endemic bovid Myotragus balearicus from localities in Mallorca (Balearis Islands, Spain) that has been explained as the result of human action, in this case deliberate trimming of the horns. The same phenomenon among Candiacervus bones and antlers (again from Crete, Greece) has been published as also being the result of human action, but this time tool-making: an ›osteokeratic culture‹. Old publications and new material – among which a recently discovered Weich- selian reindeer Rangifer tarandus antler from the Netherlands – shed another light on this phenome- non, which is explained as -gnawing by the 4 cm ruminants themselves. anaemia (comparable to the human Thalassaemia The case of the ›sick‹ Cretan bones Major syndrome) as a possible cause. This leaves us The Cretan locality of Mavro Mouri (De Vos 1984: with at least four possible causes, both pre-mortem fig. 1) has yielded a sample of bones of the endemic and post-mortem, neither of which is, however, fossil deer Candiacervus cretensis and related taxa of satisfactory. It now appears that the seemingly patho- the Cretan cervid species flock (e.g., Kuss 1975, Son- logical changes of the bones could have been caused Daar 1977, De Vos 1979). Many of these bones show by the bearded vulture Gypaetus barbatus. It is an aberrant morphology that has led researchers to thus post-mortem, and a case of taphonomy, not of various explanations. Sondaar (1977) provided the pathology. first illustration of an inflicted bone (Fig. 1a). The bones are generally thin, provided with enlarged The bearded vulture is a very large cave nesting . foramina and often a rough surface, and they have a Its diet consists of bones removed from carcasses of thin to very thin cortex. Condyles seem changed by large ungulates (Terrasse 2001). Some of these some sort of shrinkage. In general, these bones look measure up to 25 cm long. The highly acid gastric extremely unhealthy at first sight. Kuss (1975) wrote juices in its stomach extract organic substances from in a first publication about these bones: »Sie erweck- the bones, necessary for the bird’s metabolism. Occa- en zunächst den Eindruck, als handele es sich hier um sionally it happens that some swallowed bones escape krankhafte Veränderungen« (at first sight they provide complete digestion and are regurgitated inside the the impression of showing pathological changes). nest. Regurgitation after year creates an accu- In different publications, the following explanations mulation of semi-digested bones within the nesting were provided for the phenomena observed: caves. Bearded vultures still breed in Crete, Corsica boreholes made by polychaete worms of the and the Pyrenees and have recently been reintroduc- Polydora (Polychaeta, family Spionidae); this must ed in the Alps. The contents of Corsican bearded vul- have occurred at a time when high sealevel caused ture nest sites were used (by the second author) to the bones in the cave to be in contact with seawater create a taphonomic model with the aim of recogni- (Kuss 1975); a severe osteoporosis as a result of fail- sing bone accumulations in palaeontological and ure in bone formation due to malnutrition (food archaeological sites (Robert & Vigne 2002). The shortage; Sondaar 1977); malnutrition in the juve- cervid bones from Mavro Mouri were compared to nile stage leading to thinner bones during life, in this reference sample. combination with post-mortem attack of the bone by boring insects, e.g. Lepidoptera (Braber 1981); in addition, personal communications (to the first author) by staff members of the Erasmus Medical Center (Rotterdam University) suggested some Fig. 1b: Three metatarsals of Candiacervus cretensis (Pleis- tocene, Mavro Mouri cave, Crete, Greece) showing severe stages of solution due to the action of gastric juices of Gypaetus barbatus.

Fig. 2: Antler of Rangifer taran- dus (Weichselian, sand-pit between Losser and Uelsen, Dutch-German border area), showing the effect of post- mortem gnawing on the two tines.

Of the total amount of Cretan Candiacervus bones Up to three quarters of the length of the horns has recovered (Number of Identified Specimens = 1404), disappeared, leaving a stump, a remnant with a typi- 55% showed semi-digestion marks, such as enlarged cally forked appearance (Waldren 1982: pl. 26, 27|1, foramina and very thin cortical surfaces (Fig. 1b). 29, 30, 31). Waldren – who consistently wrote above This proportion is the same in the reference material ›V-trimmed horns‹ – attributed this phenomenon to from Corsica (52.5%). The most severely attacked human action, that is, prehistoric man cutting the skeletal elements are phalanges, carpals and tarsals, horns of corralled Myotragus. This was done in order and metapodials, i.e., the distal parts of the limbs. to reduce the risk of damaging each other When compared to modern ungulate bones regurgi- during fights. He corroborated this hypothesis with tated by the bearded vulture, damage locations and the known practise of Mallorcan present-day shep- damage intensity were identical. Analysing the quan- herds to saw off the horns of their goats for this pur- tity of Candiacervus bones, we can conclude that pose (Waldren, 1982: pl. 27|2, 28|2). The hypothesis successive pairs of bearded vulture probably nested came forth from the presumption that prehistoric in the Mavro Mouri cave during a few centuries, and man had lived alongside Myotragus balearicus for a in this period produced the remarkable faunal accu- considerable period of time, and that man had even mulation that has caused so much misinterpretation. attempted to domesticate or – at least – corral the The aspect of the deer bones from Mavro Mouri is . It sounds perfectly reasonable to poll cor- not due to any disease, neither to malnutrition lead- ralled (male) Myotragus-es for the purpose of avoi- ing to severe osteoporosis. All the deer present in this ding unnecessary wounds, but (1) would Myotragus cave died naturally and the vultures carried their car- really be corralled? and (2) would a practice of horn- casses inside. As malnutrition is not the reason of the trimming leave the strange rounded V-shaped phenomena, it cannot be used as an explanation for stumps? endemic morphological developments such as dwarfism, or for final of the endemic deer There is ample evidence against a long period of in the island of Crete. Island endemisms must have overlap of Myotragus and Homo. The overlap in time adaptive causes. between the first arrival of man and the demonstra- ted last occurrence of Myotragus is little (e.g., Alcover The case of the trimmed horns et al., 2001). Is seems plausible to assume that – like While Crete harboured endemic deer (Cervidae), on many other islands – the endemic fauna collapsed Mallorca – at the other end of the Mediterranean – in a short time-span after human arrival. The rather witnessed the presence of another endemic rumi- immediate introduction of sheep and goat, two nant: Myotragus balearicus (Bovidae). Waldren species that were already domesticated long before (1982) published the discovery of Myotragus baleari- human arrival on Mallorca, made attempts to cus skulls possessing highly damaged horncores. domesticate Myotragus quite obsolete. It is reasonable to envisage a quick extinction of Myotragus due to both overhunting (the ›dodo-effect‹) and probable Jelle Reumer & Isabelle Robert 55 Fig. 2: Antler of Rangifer taran- dus (Weichselian, sand-pit between Losser and Uelsen, Dutch-German border area), showing the effect of post- mortem gnawing on the two tines.

competition for food with the newly introduced the same forked pattern as the material illustrated by ruminants. We suppose that man did not try to Kuss (1969) for Candiacervus,by Waldren (1982) for domesticate the endemic ruminant because there Myotragus and by Sutcliffe (1973) who correctly was no need to do so, and hence there was no such attributed the phenomenon to the post-mortem ef- thing as a horn-trimming practice either. fect of gnawing by the Artiodactyla themselves. It is thus post-mortem, and a case of taphonomy, and not The phenomenon of V-shaped bones and antlers due of culture. to gnawing had already been published in 1973 by Sutcliffe, who gave an overview of this practice Acknowledgments among Artiodactyla. Cattle, caribou and reindeer, red The comparative study about Mavro Mouri and the deer, muntjac, camel, giraffe, wildebeest, kudu, gems- bearded vulture was supported by the CNRS (APN bok, and sable antilope all gnaw bones and antlers or program) ›Référentiels taphonomiques créés par des horns. The reason for this behaviour is the lack of agents non humains modernes‹. Mr. F. van Stuiven- phosphorous in the vegetable diet, a result from berg (Natuurmuseum Enschede, the Netherlands) either a phosphorous-poor subsoil or a calcium-rich allowed us to study the Rangifer antler. subsoil, whereby calcium reduces the availablitiy of phosphorous in plants. Mallorca consists largely of Mesozoic limestones, a calcium-rich sediment. Any bone-gnawing habit in Myotragus will thus come as no surprise. The same reasoning applies to the island of Crete, where identical forked (V-shaped) bones and antlers of the endemic deer Candiacervus creten- sis had been found and considered to be cultural relics by Kuss (1969). This author attributed the bone and antler forks to a Palaeolithic ›osteokeratic‹ cul- ture, whatever that was supposed to be. We recently found an antler of Cervus elaphus showing the same forked pattern in Mont-Lozère, France. Similarly gnawed antlers were found in the Doñana reserve, as indicated by Pérez Ripoll & Nadal (2000), who also discussed this matter after describing V-shaped horns and bones of Myotragus balearicus from the Cova des Moro (near Manacor, Mallorca). As a final proof against the theories of horn-polling or of ›osteokeratic‹ cultural practices, we recently discovered an antler of reindeer (Rangifer tarandus) from Weichselian sediments close to the Dutch-Ger- man border (Fig. 2). The antler shows, on two tines, References Alcover, J. A., Ramis, D., Coll, J. & Trias, M. (2001): Bases per al coneixement del contacte entre els primers colonitzadors humans i la naturalesa de les Balears. - Endins, 24: 5–57; Palma de Mallorca.

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