The First Complete Skeleton of Megaloceros Verticornis
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Mitt. Mus. Nat.kd. Berl., Geowiss. Reihe 5 (2002) 289-308 10.11.2002 The first complete skeleton of Megaloceros verticornis (Dawkins, 1868) Cervidae, Mammalia, from Bilshausen (Lower Saxony, Germany): description and phylogenetic implications Thekla Pfeiffer With 5 figures and 4 tables Abstract The first well preserved, articulated skeleton of a young male deer of Megaloceros verticornis (Dawkins, 1868) was excavated from early Middle Pleistocene sediments of the clay pit of Bilshausen (Unter-Eichsfeld, Lower Saxony). This find made it possible, for the first time, to establish, using cladistic techniques, the systematic position of Megaloceros verticornis among Pleistocene and Holocene plesiometacarpal and telemetacarpal cervids. By contrast to the antler and tooth characters, the postcranial characters, in particular, are suitable for phylogeny reconstruction. Megaloceros verticornb from Bilshausen shows great similarity with M. giganteus of the Upper Pleistocene of Europe in its skeletal morphology, and bootstrap values (BP = 100) show strong support for the monophyly of M. giganteus and M. verticornis. The analysis yields no evidence, however, of a close relationship between Duma and Megaloceros, which has been widely discussed in the literature because of the presence of large, palmated antlers in both genera. Key words: Pleistocene, vertebrate palaeontology, cervids, Megaloceros verticornis, skeletal morphology, phylogeny reconstruc- tion, cladistic analysis, taxonomy. Zusammenfassung Aus der Tongrube von Bilshausen (Unter-Eichsfeld, Niedersachsen) konnte das erste, vollstandige Skelett eines jungen Hirsches von Megaloceros verticornis (Dawkins, 1868) aus mittelpleistozanen Sedimentablagerungen geborgen werden. Dieser Fund ermoglichte es erstmalig, die systematische Stellung von Megaloceros verticornis im System plesiometacarpaler und tele- metacarpaler Hirsche des Pleistozans und Holozans auf breiter Basis zu untersuchen. Im Gegensatz zu den Geweih- und Zahnmerkmalen eignen sich die postcranialen Merkmale des Skelettes besonders gut fir eine phylogenetische Rekonstruk- tion der Hirsche. Die Gemeinsamkeit grol3er Schaufelgeweihe bei Duma duma und dem Riesenhirsch Megaloceros giganteus hat dazu ge- fiihrt, beide in eine enge phylogenetische Beziehung zu setzen, was in der Literatur zu einer anhaltenden Kontroverse gefiihrt hat. Die Analyse der Morphologie der postcranialen Elemente zeigt jedoch, dass es keine enge Verwandtschaft zwischen Duma und Megaloceros gibt. Schliisselworter: Pleistozan, Wirbeltierpalaontologie, Cerviden, Megaloceros verticornis, Skelettmorphologie, phylogenetische Rekonstruktion, kladistische Analyse, Taxonomie. Introduction vestigations ceased during the second world war, and some material was lost, but fortunately the In the early 20th century, Schmidt (1930, 1934) best preserved find of the early years, the articu- recovered a complete skeleton of AZces Zutifrons lated skeleton of A. Zutifrons, was later discov- from the clay pit of Bilshausen (Lower Saxony, ered in the Museum of the Institute for Palaeon- 20 km SE Gottingen), and several finds of articu- tology at the University of Gottingen. lated skeletal elements of large mammals were This museum also houses the well preserved brought to light in the following years. In 1952 skeleton of a young male deer of MeguZoceros the complete extremities of another large cervid verticornis from Bilshausen (Fig. 1) excavated by were found embedded in the clay, although the D. Meischner and J. Schneider (both at the body was dislocated and destroyed. Scientific in- University of Gottingen) in November 1964 I Gutswiese 21, D-38162 Cremlingen, Germany. Received April, accepted July 2002 290 F‘feiffer. T.. ComDlete skeleton of Mepaloceros Fig. 1. The first articulated skeleton of a young male of Meguloceros verticornis (Dawkins, 1868) from Bilshausen. (Meischner & Schneider 1967). Pollen analysis of Brockentuff of Karlich, 396,000 +/- 20,000 mea- the interglacial profile from Bilshausen was car- sured using the 40Ar/”Ar laser method by v. d. ried out by Muller (1965), and Gruger et al. Bogaard et al. (1989) was fully compatible with (1994) who made detailed studies of the Middle the dating suggested by Bittmann & Miiller Pleistocene warm phases of this area. Bittmann (1996) on the basis of the vegetational develop- & Miiller (1996) correlated the Karlich Inter- ment. The taphonomy of Bilshausen was inter- glacial site with Bilshausen. The age of the preted by Meischner (1995) as follows: “Bils- Mitt. Mus. Nat.kd. Berl., Geowiss. Reihe 5 (2002) 291 hausen was during its existence a meromictic within the Pleistocene plesiometacarpal deer for pond ... fishes and mammals abound in the the first time. Analysis of the morphology of the warved black shales. The skeleton of the giant postcranial skeletal elements verifies a close rela- deer showed no remnants of the skin, but the tionship between M. verticornis and M. gigun- arrangement of the bones indicate that the teus. corpse sank to the bottom, fell on the right side, Gould (1974) showed that the dramatic size and came to rest head-down on a slope. Bones reduction of spike antlers in the advanced South maintained their original arrangement, but be- American genera Pudu and Muzania suggests came disarticulated and were partly rotated, that the reversal of morphological trends is pos- partly pulled-apart, by downslope movement of sible as a consequence of selection correlated the still soft sediment.” The skeleton of the with small body size. Some morphological char- young male deer of Megaloceros verticornis is acters seem therefore to be with highly homo- especially important because it is the first articu- plastic in ungulates (Scott & Janis 1993), and are lated skeleton found for this species. difficult to use for determining phylogenetic rela- Fossil and recent cervids have been described tionships. primarily on the basis of antler-, skull- and tooth characters, and additionally on body size. Cur- rent morphological taxonomy splits the family Material Cervidae on the basis of a single character: ab- sence (Hydropotinae) or presence (Odocoileinae The analysis conducted here was based on skeletons from + Cervinae) of antlers (Groves & Grubb 1987), males and females of a large number of Recent and fossil even though the taxonomic value of antlers has deer species, and the skeleton of Megaloceros verticornis from Bilshausen (Table 1). This taxon list includes the Re- been repeatedly questioned (see, for example, cent telemetacarpal species Alces alces, Rangifer tarandus, Scott & Janis 1993). Antlers show high varia- Capreolus capreolus, C. pygargus, the Middle Pleistocene bility within a species, and this is dependent on on- Roe deer C. suessenbomensis, the Lower Pleistocene plesio- metacarpal species Eucladoceros tegulensis, E. dicranios, togenetic growth patterns and habitat conditions. Dama rhenana, Dama nestii, the Middle Pleistocene Megalo- Unfortunately, previous workers attempted to ceros verticornis, M. giganteus, Cervus elaphus acoronatus, ascertain relationships of cervids based only on Dama darna clactoniana, D. duma geiselana, and the extant forms Cervus elaphus, C. nippon nippon, C. nippon hortulor- the comparison of antler and skull characters. An um, Axis axis, D. darna mesopotamica, and D. darna darna. example of this problem is the unresolved discus- Skeletons of the Recent Moschus rnoschiferus and skeletal sion concerning the relationships of the Recent material of the taxa Blastomeryx and Parablastomeryx from the Miocene of North America were added as outgroups. fallow deer (Duma duma) and the giant deer In addition to skeletons, isolated bones of fossil taxa from (Megaloceros giganteus) which stemms from the different localities were also used. The scapula and pelvis, beginning of the last century. The presence of like the skull, were often broken. In the case of Megaloceros verticornis, the skeleton of the young stag from Bilshausen large, palmated antlers in Dama duma and Mega- was analysed together with skulls, antlers and isolated post- loceros giganteus suggested a close relationship cranial bones of adult individuals from SiiBenborn and Voigt- between these two taxa (Freudenberg 1914, Geist stedt. Because the skull of the deer from Bilshausen is not preserved and this specimen reprents a juvenile, it was neces- 1971, 1987, Lister 1984). By contrast Thenius sary to study additional elements from adult individuals. (1958) and Kahlke (1994) held the view that the giant deer must have evolved from deer with an- tlers that lacked any palmation. Investigations by Method Pfeiffer (1999a, in press) that also include post- cranial characters, show that the genera Megulo- A data matrix was coded for the 20 fossil and Recent deer ceros and Duma belong to clearly separate listed above, and the antlerless musk deer, Moschus moschi- ferus, together with Blastomeryx and Parablastorneryx from lineages in the Pleistocene, and that their pal- the Miocene of North-America were used as outgroups. In mate antlers must have evolved independently. current taxonomy, Moschus is commonly accepted as a close The systematic position of Meguloceros verti- relative of the family Cervidae. Blastomeryx and Parablasto- meryx share many ancestral features with early cervids in- cornis has also been controversial (see below). cluding, for example, large upper canines. On the basis of the skeleton from Bilshausen, The one-hundred and twenty-two morphological characters and together with skulls, antlers, and selected