Roman Croitor
email: romancroitor@europe.com

Ion Cojocaru

An Antlered Skull of a Subfossil Red Deer, Cervus elaphus L., 1758 (Mammalia: Cervidae), from Eastern Romania

Keywords: Carpathian red deer, Cervus elaphus maral, morphology, systematics, taxonomy, Romania 1898: p. 79

A subfossil antlered braincase of red deer discovered in the Holocene gravel deposits of Eastern Romania is described. The morphology of antlers suggests that the studied specimen is related to the Caucasian and Caspian stags and belongs to the oriental subspecies Cervus elaphus maral OGILBY, 1840. An overview and discussion of taxonomical issues regarding modern red deer from South-eastern Europe and some fossil forms of the region are proposed. The so-called Pannonian red deer (Cervus elaphus pannoniensis BANWELL, 1997) is considered a junior synonym of Cervus elaphus maral OGILBY, 1840. Cervus elaphus aretinus AZZAROLI, 1961 from the last interglacial stage of Italy seems to be very close to Cervus elaphus maral.

Introduction

The subspecies status and systematic position of the red deer from the Carpathian Mts. is still a matter of discussions. The comparatively larger Carpathian red deer has massive antlers with less developed crown tines as compared to the red deer subspecies from Western Europe. It was assigned to two subspecies, C. vulgaris montanus BOTEZAT, 1903 (the "mountain common deer") and C. vulgaris campestris BOTEZAT, 1903 (the "lowland common deer"). [START_REF] Botezat E | Gestaltung und Klassifikation der Geweihe des Edelhirsches, nebst einem Anhange über die Stärke der Karpathenhirsche und die zwei Rassen derselben[END_REF] proposed for red deer species the name Cervus vulgaris, since, according to his opinion, the Linnaean Greek-Latin name Cervus elaphus is tautological. [START_REF] Lydekker | Artiodactyla, Families Cervidae (Deer), Tragulidae (Chevrotains), Camelidae (Camels and Llamas), Suidae (Pigs and Peccaries), and Hippopotamidae (Hippopotamuses)[END_REF] and [START_REF] Grubb P | Valid and invalid nomenclature of living and fossil deer, Cervidae[END_REF] considered the name C. vulgaris as a junior synonym of C. elaphus. LYDEKKER (1898) included the Eastern Carpathians in the geographical range of the Caspian red deer Cervus elaphus maral OGILBY. Nonetheless, in his later publication, [START_REF] Lydekker | Artiodactyla, Families Cervidae (Deer), Tragulidae (Chevrotains), Camelidae (Camels and Llamas), Suidae (Pigs and Peccaries), and Hippopotamidae (Hippopotamuses)[END_REF] generally accepted BOTEZAT's viewpoint on the taxonomical distinctiveness between the two Carpathian forms of red deer. However, LYDEKKER (1915) indicated that C. vulgaris campestris is preoccupied since it has been used as Cervus campestris CUVIER, 1817 (a junior synonym of Odocoileus virginianus). Therefore, [START_REF] Lydekker | Artiodactyla, Families Cervidae (Deer), Tragulidae (Chevrotains), Camelidae (Camels and Llamas), Suidae (Pigs and Peccaries), and Hippopotamidae (Hippopotamuses)[END_REF] considered the red deer from the typical locality Marmoros and Bukovina districts of the Hungarian and Galician Carpathians as Cervus elaphus ssp. According to [START_REF] Lydekker | Artiodactyla, Families Cervidae (Deer), Tragulidae (Chevrotains), Camelidae (Camels and Llamas), Suidae (Pigs and Peccaries), and Hippopotamidae (Hippopotamuses)[END_REF] this deer may be to some degree intermediate between Cervus elaphus germanicus from Central Europe and Cervus elaphus maral from Northern Iran and Caucasus. With some doubts, [START_REF] Lydekker | Artiodactyla, Families Cervidae (Deer), Tragulidae (Chevrotains), Camelidae (Camels and Llamas), Suidae (Pigs and Peccaries), and Hippopotamidae (Hippopotamuses)[END_REF] included C. vulgaris montanus in the synonymy of Cervus elaphus maral and suggested that both Carpathian red deer forms described by BOTEZAT may represent recently immigrated dwarfed forms of C. elaphus maral. [START_REF] Heptner | Deer of the USSR (Systematics and Zoogeography). -Transactions on Study of Fauna and Flora of the USSR[END_REF] also rejected BOTEZAT's subspecies name campestris as preoccupied; however, they recognized the validity of Cervus elaphus montanus BOTEZAT with type locality in Bukovina (Romania) and the vast area of distribution that included the entire Carpathian-Balkan region. This subspecies is characterised by underdeveloped neck mane, the missing black stripe bordering the rump patch (or caudal disk), generally grayish colour of pelage, poorly developed distal crown in antlers, and comparatively larger body size [START_REF] Heptner | Deer of the USSR (Systematics and Zoogeography). -Transactions on Study of Fauna and Flora of the USSR[END_REF]. [START_REF] Flerov | Musk deer and deer. The Fauna of USSR[END_REF] and [START_REF] Sokolov | Hoofed animals (Orders Perissodactyla and Artiodactyla). Fauna of the USSR[END_REF] placed the Carpathian red deer in the nominotypical subspecies Cervus elaphus elaphus Linnaeus since the diagnostic characters of antler morphology, pelage colour as well as body size used for the description of the Carpathian red deer are not constant characters and, therefore, are not suitable for subspecies designation. According to [START_REF] Flerov | Musk deer and deer. The Fauna of USSR[END_REF], the morphological peculiarities of the Carpathian and Crimean red deer are insignificant and do not permit to place those populations in any separate subspecies. ALMAŞAN et al. (1977) referred the Carpathian red deer to the Central European subspecies Cervus elaphus hippelaphus ERXLEBEN, 1777. According to [START_REF] Danilkin | Deer (Cervidae). (Series: Mammals of Russia and adjacent regions)[END_REF], the "Carpathian race" montanus is a transitional form between the Western European C. elaphus elaphus and the Caucasian C. elaphus maral. [START_REF] Tatarinov | Mammals of Western Regions of Ukraine[END_REF] applied a new subspecies name Cervus elaphus carpathicus for the red deer from the Ukrainian part of the Carpathian Mts. [START_REF] Heptner | Artiodactyla and Perissodactyla[END_REF] regarded TATARINOV's subspecies as a junior synonym of campestris and montanus and considered it as a nomen nudum. [START_REF] Grubb P | Valid and invalid nomenclature of living and fossil deer, Cervidae[END_REF] considered C. vulgaris campestris BOTEZAT and C. vulgaris montanus BOTEZAT as homonyms of Cervus campestris CUVIER, 1817 and Cervus montanus CATON, 1881, respectively, and, therefore, both names were suggested to be invalid. [START_REF] Banwell | The Pannonians -Cervus elaphus pannoniensis -a race apart[END_REF] proposed another new subspecies name, Cervus elaphus pannoniensis, for red deer from Hungary, Romania and the Balkan Peninsula. [START_REF] Banwell | The Pannonians -Cervus elaphus pannoniensis -a race apart[END_REF][START_REF] Banwell | Identification of the Pannonian, or Danubian, Red Deer[END_REF] described a set of specific morphological characters that distinguish the so-called "maraloid" Pannonian red deer from the Western European red deer. However, BANWELL did not provide the diagnostic characters distinguishing Cervus elaphus pannoniensis from Cervus elaphus maral. Nonetheless, BANWELL 's subspecies C. elaphus pannoniensis was accepted by several authors (GROVES & GRUBB 2011; MARKOV 2014) and even its taxonomic status was raised to the species level [START_REF] Groves C | Ungulate Taxonomy[END_REF]. [START_REF] Zachos | Species inflation and taxonomic artefacts -A critical comment on recent trends in mammalian classification[END_REF] regard the full-species status for the Pannonian red deer as an objectionable "taxonomic inflation". [START_REF] Geist | Deer of the World: Their Evolution, Behaviour and Ecology[END_REF], in his comprehensive publication on evolution, biology and systematics of red deer and wapiti (C. elaphus canadensis ERXLEBEN, 1777, or Cervus canadensis according to the latest genetic studies, see e.g. [START_REF] Polziehn | A Phylogenetic Comparison of Red Deer and Wapiti Using Mitochondrial DNA[END_REF], did not indicate explicitly the systematical position of the Carpathian red deer. However, he supported BOTEZAT's idea on the presence of two forms of red deer in the Carpathian region. According to [START_REF] Geist | Deer of the World: Their Evolution, Behaviour and Ecology[END_REF] 1777) who first applied this name for the red deer from Germany and Ardennes and gave its scientific description supplemented with synonymy and detailed bibliographic references. Later, KERR (1792) applied the species and subspecies name Cervus elaphus hippelaphus ("maned stag") with a reference to ERXLEBEN's (1777) work.].

The recently published results on genetic analysis of red deer populations from Western Eurasia bring new views on systematic position and taxonomical status of red deer from the Carpathian region. According to [START_REF] Ludt Ch | Mitochondrial DNA phylogeography of red deer (Cervus elaphus)[END_REF], the analysis of mtDNA cytochrome b sequence could not distinguish the red deer from the Balkan-Carpathian region from the red deer forms of Central and Western Europe. However, the study of [START_REF] Ludt Ch | Mitochondrial DNA phylogeography of red deer (Cervus elaphus)[END_REF] confirmed the subspecies status of C. elaphus barbarus from North Africa, C. elaphus maral from the Caspian Region, and C. elaphus bactrianus and C. elaphus yarkandensis from Central Asia. All the mentioned subspecies and forms of red deer are included in the so-called Western group of red deer. KUZNETZOVA et al. (2007) confirmed that the molecular-genetic analysis of red deer from Eastern Europe did not support the validity of red deer subspecies C. elaphus montanus from the Balkan-Carpathian area and C. elaphus brauneri from Crimea as well as C. elaphus maral from North Caucasus. The genetic integrity of the Carpathian populations of red deer was confirmed through the haplotype distribution, private alleles and genetic distances [START_REF] Feulner | Mitochondrial DNA and microsatellite analyses of the genetic status of the presumed subspecies Cervus elaphus montanus (Carpathian red deer)[END_REF]. Therefore, the complicated ancestral pattern for Carpathian red deer suggested by [START_REF] Geist | Deer of the World: Their Evolution, Behaviour and Ecology[END_REF] was not supported. [START_REF] Skog | Phylogeography of red deer (Cervus elaphus) in Europe[END_REF] and [START_REF] Zachos | Phylogeography, population genetics and conservation of the European red deer Cervus elaphus[END_REF] suggested that the modern Carpathian red deer had originated from the Balkan Late Glacial refugium. [START_REF] Skog | Phylogeography of red deer (Cervus elaphus) in Europe[END_REF] also assumed that the Balkan Late Glacial refugium could extend further to the south-east (Turkey and Middle East). [START_REF] Sommer | Late Quaternary distribution dynamics and phylogeography of the red deer (Cervus elaphus) in Europe[END_REF] regarded Moldova (East Carpathian foothills) as a part of the East European Late Glacial refugium.

However, a certain caution is needed with the results of the genetic analysis. [START_REF] Micu | Ungulates and their management in Romania[END_REF] reported that the Austrian red deer with multi-tine crowns were introduced to Romania in the 19th and early 20th centuries in order to "improve" the quality of antlers of the local red deer race. Therefore, although the level of genetic introgression may be low, the modern populations of Carpathian red deer are not truly natural anymore (ZACHOS & HARTL 2011).

The taxonomic status and systematic position of the Carpathian red deer is complicated further by the fact that the previously published data on morphology of Cervus elaphus from the Carpathian Region are poor and quite superficial (ALMAŞAN et al. 1977;[START_REF] Saraiman | Prezenţa speciilor Bos primigenius Boj. şi Cervus elaphus L., în terasa de 8-10 m a Siretului. -Analele ştiinţifice ale Universităţii[END_REF].

In the context of the above-mentioned controversies, the new subfossil material of red deer from the Carpathian Region represents a special interest and may elucidate the systematic position of the aboriginal red deer forms. In the present work, we propose a morphological description of the well preserved antlered braincase from Holocene gravel deposits in Eastern Romania and a discussion on the systematic position of the original red deer from the Eastern Carpathian area.

Material and Methods

The studied specimen represents an antlered braincase with almost complete left antler and proximal part of the right antler. The specimen was discovered in a gravel pit located in the area of Răchiteni Village, Iasi County, north of the Roman town (Fig. 1). Most likely, the gravel deposits from Răchiteni are of Post-Glacial (Holocene) age (Paul TIBULEAC, personal communication). The cranial measurements are taken according to von den DRIESCH (1976). The antler measurements are taken following [START_REF] Heintz E | Les cervidés villafranchiens de France et d'Espagne. -Mémoires du Muséum[END_REF]. The terminology of antler morphology is according LISTER (1996).

Results

Systematics

Genus Cervus LINNAEUS, 1758

Cervus elaphus LINNAEUS, 1758

Cervus elaphus maral OGILBY, 1840

Description

The antlered skull of red deer from Răchiteni belongs to a mature but not old male individual: its pedicles are rather short and robust (their height is significantly smaller than their diameter; Table 1, Fig. 2), the bone sutures of neurocranium are still visible but in some places (the area between pedicles) are completely obliterated and, therefore, indicate the fully mature age (MYSTKOWSKA 1966). We assume, therefore, that the antlers of the red deer from Răchiteni most probably attained their maximal development.

The cranial measurements of the specimen suggest that the individual from Răchiteni was rather large, exceeding body size of modern red deer from Bialowieza Forest and Caucasus. The greatest breadth of the skull across orbits in males of Cervus elaphus hippelaphus from Bialowieza Forest (three individuals) range 165-181 mm; the breadth of occipital condyles ranges 72-76 mm [START_REF] Heptner | Deer of the USSR (Systematics and Zoogeography). -Transactions on Study of Fauna and Flora of the USSR[END_REF]. The analogous measurements of males of Cervus elaphus maral from Caucasus (nine individuals) range 145-187 mm, and from 67 mm to 80 mm, respectively [START_REF] Heptner | Deer of the USSR (Systematics and Zoogeography). -Transactions on Study of Fauna and Flora of the USSR[END_REF]. The corresponding measurements of the skull from Răchiteni were greater than the measurements of the largest Caucasian stag reported by HEPTNER & ZALKIN (1947) with ca. 1 cm (the greatest breadth across the orbits and the breadth of occipital condyles were 198.0 mm and 87.8 mm, respectively).

The antlers from Răchiteni were characterized by a comparatively long curved brow (first) tine situated at a short distance from the burr, the missing bez (second) tine, and the rather long and strong trez (third) tine, which is, however, shorter than the brow tine (Table 2). The antler beam was somewhat bent toward the posterior at the level of trez tine insertion and after slightly arched acquiring the upright orientation in lateral view. The distal portion of antler formed a crown that consisted of six tines (Fig. 3). Therefore, the total number of antler tines amounted to eight. The crown of antler was formed by two transversely oriented forks, the additional prong and the apical tine (broken). The antler beam was curved towards the posterior in the area of distal crown and formed the pointed posterior axe of the crown, reminding the morphological pattern typical of the Caucasian and Caspian red deer C. elaphus maral (LYDEKKER 1915: 127, fig. 23). The antler surface was covered with a characteristic "pearling" specific for the so-called Western group of red deer [START_REF] Geist | Deer of the World: Their Evolution, Behaviour and Ecology[END_REF].

Discussion

According to LYDEKKER (1898), the number of tines of Cervus elaphus maral seldom exceeded eight. GEIST (1998) described the antlers of Carpathian stags as large, heavy but poorly branched as compared to Western European red deer. LYDEKKER (1898) reported also a frequent poor development of bez tine in Cervus elaphus maral. According to LYDEKKER (1898), the bez tine was often much shorter than brow tine or even might be absent in the Carpathian red deer, as could be seen in the case of the specimen from Răchiteni.

The antlers of red deer from Prăjeşti (Siret Valley) described by [START_REF] Saraiman | Prezenţa speciilor Bos primigenius Boj. şi Cervus elaphus L., în terasa de 8-10 m a Siretului. -Analele ştiinţifice ale Universităţii[END_REF] also show a rather weak bez tine, which is less developed than brow tine and much shorter than trez tine. The distal crown in two better preserved larger antlers from Prăjeşti (SARAIMAN & ŢARĂLUNGĂ 1978: Pl. V, figs. 1, 2) is rather weak. It consists of four tines, of which the first crown tine is much distinct in the crown as in modern Caspian deer (see the description in LYDEKKER 1898). Therefore, the crown shape of red deer from Prăjeşti resembles the typical morphological condition seen in the Caucasian and Caspian red deer. The remains of red deer from Prăjeşti have been found together with a fragment of skull of Bos primigenius. [START_REF] Saraiman | Prezenţa speciilor Bos primigenius Boj. şi Cervus elaphus L., în terasa de 8-10 m a Siretului. -Analele ştiinţifice ale Universităţii[END_REF] have suggested the Würmian age for the osteological remains from Prăjeşti. [START_REF] Spassov | The Remains of Wild and Domestic Animals from the Late Chalcolithic Tell Settlement of Hotnitsa (Northern Bulgaria)[END_REF] described from the Late Chalcolithic (4100-4500 BC) of North Bulgaria remains of a very large form of red deer that rivalled the size of Siberian maral Cervus canadensis. Besides the larger size, the subfossil red deer from Bulgaria was characterised by massive antler beams, a simplified antler crown and a relatively limited number of tines. This brief description generally corresponds to the characteristics of the Caucasian and Caspian red deer Cervus elaphus maral LYDEKKER, 1898, and suggests its close resemblance to the Romanian subfossil red deer. The larger size of the subfossil red deer, as compared to the modern forms from the same area, is explained by the long tradition of trophy hunting that has likely led to dwarfing of the populations of game species [START_REF] Spassov | The Remains of Wild and Domestic Animals from the Late Chalcolithic Tell Settlement of Hotnitsa (Northern Bulgaria)[END_REF].

Understanding the significance of the observed peculiarities of antler morphology of fossil and subfossil red deer from Eastern Romania and neighbouring countries, and their resemblance to the Caucasian and Caspian modern red deer, requires a discussion of already described taxa of red deer from Southeastern Europe. A conspicuously weak bez tine may be also noticed in the modern Crimean deer, which is often regarded as a true subspecies: Cervus elaphus brauneri [START_REF] Charlemagne N | Les Mammiferes de l'Oukraine. Court manuel de determination, collection et observation des mammiferes de l'Oukraine[END_REF]. DANILKIN (1999: fig. 122-2) presented the antlered skull of Crimean red deer from the collection of the Zoological Museum of the Moscow State University that shows a very weak bez tine on the left antler and a missing bez tine on the right antler, while its distal crown reminds the morphological condition of Cervus elaphus maral.

The origin of the modern Crimean population is not clear and its taxonomic status is controversial. FLEROV (1952: 162) placed the Crimean stag in an informal group together with the Balkan and Carpathian red deer within the European subspecies Cervus elaphus elaphus, since, according to his opinion, the morphological peculiarities of the above mentioned populations are not taxonomically significant. SOKOLOV (1959: 219) also considered that the separation of the Crimean subspecies brauneri is not justified. Nonetheless, HEPTNER et al. (1988) believed that the Crimean deer represented a taxonomically independent form that occupied an intermediate position between the Carpathian and Caucasian red deer. [START_REF] Danilkin | Deer (Cervidae). (Series: Mammals of Russia and adjacent regions)[END_REF] regarded the Crimean population of red deer as a small-sized "insular" form of North-Caucasian red deer that was introduced in Crimea in the early 20th century. Finally, VOLOKH (2012) reported multiple and uncontrolled introductions of red deer individuals to Crimea at least from the times of the Crimean Khanate until very recent times. Therefore, the debates on the taxonomical status of the modern Crimean red deer become useless. [START_REF] Ludt Ch | Mitochondrial DNA phylogeography of red deer (Cervus elaphus)[END_REF] discovered that the modern red deer from Crimea belongs to the haplogroup of Western European red deer. However, this conclusion was based only on two modern specimens from Crimea. Obviously, the adequate results of genetic analysis could be obtained only from subfossil and archaeozoological remains. [START_REF] Stankovic | First ancient DNA sequences of the Late Pleistocene red deer (Cervus elaphus) from the Crimea, Ukraine[END_REF] analysed the ancient DNA sequences of Late Pleistocene red deer from Crimea and revealed a very interesting fact: the Crimean Peninsula was colonized several times by various forms of red deer of different zoogeographic origin: the youngest form of red deer from Crimea (two specimens dated 33.100 ± 400 BP and 42.000 ± 1200 BP) are genetically close to C. elaphus songaricus from China, while the older specimen (>47,000 BP) is close to the Balkan populations of red deer. The origin of indigenous Holocene Crimean population of red deer still remains unclear. It is necessary to mention that the subfossil red deer from Crimea (early Iron Age, settlement of Uch-Bash, Sevastopol) is characterised by a peculiar high frequency of primitive unmolarised lower fourth premolar (P4), which distinguishes this population from Cervus elaphus of Western Europe (CROITOR, 2012).

The recently established new subspecies

Cervus elaphus pannoniensis BANWELL, 1997 from the Middle Danube area also requires a special discussion here. Although [START_REF] Banwell | The Pannonians -Cervus elaphus pannoniensis -a race apart[END_REF][START_REF] Banwell | Identification of the Pannonian, or Danubian, Red Deer[END_REF] had the opportunity to see the red deer from Anatolia and the Balkan Peninsula, the description of his new subspecies was based only on morphological differences between the so-called Pannonian red deer and Western European ("Atlantic") Cervus elaphus hippelaphus, while a differential diagnosis between Cervus elaphus pannoniensis and Cervus elaphus maral and a comparison of these two subspecies were not provided. The antlered skull from Southern Hungary (displayed in the Chateau Chambord) presented by [START_REF] Banwell | The Pannonians -Cervus elaphus pannoniensis -a race apart[END_REF], should be considered as a type specimen (lectotype according to GROVES & GRUBB 2011). Its extremely large antlers bear additional long tines on its beams and crowns, well-developed both brow and bez tines and apparently represent an exceptional hunter's trophy specimen. BANWELL (1998) provides a good and very detailed morphological description of the Pannonian red deer, which are distinguished from the Western European forms, according to the description, by the larger size and elongated Romannosed face (obviously, these two characters are correlated), poorly developed mane, underdeveloped caudal disk, large antlers with poorly developed distal crown. Finally, as BANWELL (1997,1998,2002) reasonably noticed, the Pannonian red deer belongs to the Oriental "maraloid" type. The area of distribution of the new Pannonian subspecies includes, according to BANWELL (1998), Hungary, Romania, the Western Balkan states, Bulgaria, and may range until Crimea, Eastern Turkey and Iran. One can notice that the assumed area of distribution of BANWELL's subspecies broadly overlaps with the known area of distribution of Cervus elaphus maral. Although [START_REF] Groves C | Ungulate Taxonomy[END_REF] affirm that BANWELL has provided a set of characters (colour, spotting, mane and antlers) distinguishing Cervus elaphus pannoniensis from Cervus elaphus maral, such data are not available. The latter subspecies was ignored in BANWELL's (1994,1997,1998,2002) publications. Therefore, taking in consideration the absence of distinguishing diagnostic characters and the overlapping of claimed areas of distribution, we regard Cervus elaphus pannoniensis BANWELL as a junior synonym of Cervus elaphus maral OGILBY.

Most probably, the studied fossil and sub-fossil Carpathian red deer are also closely related to Cervus elaphus aretinus AZZAROLI, 1961 from the last interglacial phase of Val di Chiana (Central Italy). The Italian fossil red deer is characterised by a presence of only one basal tine (the brow tine) and a massive distal crown, which, however, still resembles the maral type (Fig. 4). It is necessary to mention here the observed by [START_REF] Banwell | Identification of the Pannonian, or Danubian, Red Deer[END_REF][START_REF] Banwell | In defence of the Pannonian Cervus elaphus pannoniensis[END_REF] development of slight distal palmation in the so-called Pannonian red deer; in our opinion, this also makes it similar to Cervus elaphus aretinus. One of the authors of the present study [START_REF] Croitor R | Functional morphology of small-sized deer from the early and middle Pleistocene of Italy: implication to the paleolandscape reconstruction[END_REF][START_REF] Croitor R | Early Pleistocene small-sized deer of Europe[END_REF] assumed in his previous publications that Cervus elaphus aretinus (or Cervus aretinus) represents a local archaic specialized form. However, the morphological resemblance between the fossil form Cervus elaphus aretinus and the modern Cervus elaphus maral, in our opinion, is obvious and one may not exclude that those two subspecies could be even synonymous. Another antlered fragment of skull that strongly reminds the morphology of Cervus elaphus maral is reported from the Late Pleistocene of Liguria (Le Prince, Italy; BARRAL & SIMONE 1968: 87, Figs. 14-1).

Apparently, the origin of the indigenous Carpathian red deer is linked to the Balkan-Anatolian-Caucasian glacial refugium [START_REF] Sommer | Late Quaternary distribution dynamics and phylogeography of the red deer (Cervus elaphus) in Europe[END_REF][START_REF] Skog | Phylogeography of red deer (Cervus elaphus) in Europe[END_REF][START_REF] Meiri | Late-glacial recolonization and phylogeography of European red deer[END_REF]. The Italian Cervus elaphus aretinus could be very close also to the red deer form from the glacial refugium in Eastern Europe. The placement of the postglacial Carpathian red deer in the subspecies Cervus elaphus maral, according to our opinion, is supported by the reported in the present study antler morphology. Nonetheless, the history of the red deer from the Carpathian-Balkan area and the adjacent regions requires a more complex and extensive interdisciplinary research combining zoological, archaeozoological, palaeontological and genetic data in the future.

Fig. 1 .

 1 Fig. 1. Geographical location of the Răchiteni site, Iaşi County, Romania

Fig. 2 .

 2 Fig. 2. Cervus elaphus maral OGILBY from Răchiteni: A, lateral view of the braincase; B, occipital view of the braincase; C basal view of the braincase.

Fig. 3 .

 3 Fig. 3. Cervus elaphus maral OGILBY from Răchiteni: A, frontal view; B lateral view; C medial view of left antler.

Fig. 4 .

 4 Fig. 4. Cervus elaphus aretinus AZZAROLI from the last interglacial phase of Val di Chiana, Italy (adapted from AZZAROLI 1961): A frontal view of antlered frontlet; B lateral view of antler crown.

, European west (C. elaphus elaphus) and east (C. elaphus maral) types of red deer meet in the Balkans. Within this context, GEIST (1998) also discussed the so-called "cave stag", Strongyloceros spelaeus OWEN, 1846 from Western Europe, a Glacial Age wapiti that rivalled the size of the giant deer Megaloceros giganteus Blumenbach, 1799. GEIST (1998), taking in consideration PHILIPOWICZ's (1961) description of the Carpathian red deer, presumed that the largest European red deer

  with somewhat simplified smooth antlers (not pearled as in West European red deer) from the Carpathian Alpine meadows is a descent of the giant Glacial Age wapiti. Later,[START_REF] Geist V | Defining subspecies, invalid taxonomic tools, and the fate of the woodland caribou[END_REF] placed the Carpathian red deer in Central European subspecies Cervus elaphus hippelaphus KERR, 1792 [Sic! The authorship of subspecies Cervus elaphus hippelaphus belongs to ERXLEBEN (

Table 1 .

 1 Measurements of the skull of Cervus elaphus maral OGILBY from Răchiteni (measurements are numbered according to von den Driesch 1976: fig. 11).

	Measurements	mm	notes
	dorsal view
	(10) Median frontal length	198.0 incompletely preserved
	(11) Lambda -Nasion	152.0 incompletely preserved
	(31) Least frontal breadth	178.0 orbits incompletely preserved
	(32) Greatest breadth across the orbits	198.0 orbits incompletely preserved
	(41) distal circumference of the burr	211.0 in both antlers
	Distance between antler burrs	79.8
	Distance between pedicles and nucal crest	113.0
	lateral view
	(38) basion -the highest point of the superior nuchal crest	97.0
	(40) proximal circumference of the burr	190.0
	bazal view
	(6) basicranial axis	130.0 basicranium length
		91.0	taken from the visible suture to the posterior
			edge
	(26) Greatest breadth of occipital condyles	87.8
	(28) Greatest breadth of the foramen magnum	35.4
	(27) Greatest breadth at the bases of the paraoccipital	158.0 incompletely preserved
	processes

Table 2 .

 2 Measurements of the antlers of Cervus elaphus maral OGILBY from Răchiteni.

Acknowledgements:

We thank Adrian LISTER, Nikolai SPASSOV and Stefano MATTIOLI for their kindness while providing missing bibliographical sources used in this research.


I Egry

D M Herlach

L Ratke

M Kolbe

D Chatain

S Curiotto

L Battezzati

E Johnson

N Pryds

Interfacial properties of immiscible Co-Cu alloys

Keywords: miscibility gap, interfacial tension, surface tension, levitation, oscillating drop, microgravity

Using electromagnetic levitation under microgravity conditions, the interfacial properties of an Cu 75 Co 25 alloy have been investigated in the liquid phase. This alloy exhibits a metastable liquid miscibility gap and can be prepared and levitated in a configuration consisting of a liquid cobalt-rich core surrounded by a liquid copper-rich shell. Exciting drop oscillations and analysing the frequency spectrum, both surface and (liquid-liquid) interfacial tension can be derived from the observed oscillation frequencies. This paper briefly reviews the theoretical background and reports on a recent experiment carried out on board the TEXUS 44 sounding rocket.

Introduction

Alloys with a metastable miscibility gap are fascinating systems due to the interplay between phase separation and solidification. In contrast to systems with a stable miscibility gap, the demixed microstructure can be frozen in by rapid solidification from the undercooled melt. Electromagnetic levitation offers the possibility to study compound drops consisting of a liquid core, encapsulated by a second liquid phase. The oscillation spectrum of such a compound drop contains information about both, the surface and the interface tension. The binary monotectic alloy CuCo is an ideal model system for such investigations. Its phase diagram is shown in Figure 1.

In order to study this system, including potential industrial applications, the European Space Agency ESA funded a European project, COOLCOP [1]. In the past years, this team devoted a lot of effort to understand the behaviour of such systems, starting from phase diagram calculations [2], drop dynamics [3], modelling of interfacial properties [4], and extending to solidification theories and experiments [5]. The investigations laid the ground for microgravity experiments. First results for a Co 25 Cu 75 alloy onboard a sounding rocket are reported here.

As the temperature of a homogeneous melt of the alloy is lowered below the binodal temperature, demixing sets in and small droplets of one liquid, L1, in the matrix of the other liquid, L2, are formed. These two immiscible liquids do not consist of the pure components, but have concentrations according to the phase boundary of the miscibility gap; therefore, L1 is rich in component 1, while L2 is rich in component 2. Initially, depending on the nucleation kinetics, a large amount of liquid droplets is created. This initial phase is energetically very unfavourable, due to the high interface area created between the different drops. In the next stage, Ostwald ripening sets in [START_REF] Ratke | Immiscible Liquid Metals and Organics[END_REF]. This diffusive mechanism leads to the growth of large drops at the expense of the small ones, thereby coarsening the structure of the dispersion and finally leading to two separated liquid phases. For a levitated drop, without contact to a substrate, the liquid with the lower surface tension -in the present case the copper-rich liquidencapsulates the liquid (cobalt-rich) core. Terrestrial levitation experiments suffer from the detrimental side effects of the levitation field, in particular by electromagnetic stirring effects which destroy the separated two-phase configuration. Therefore, it was decided to perform such an experiment under microgravity conditions on board a TEXUS sounding rocket. As will be discussed below, the drawback of this carrier is the short available experiment time of about 160 s. Due to a specific preparation of the sample, it was nevertheless possible to conduct three melting cycles during this short time.

Drop Dynamics

Generally speaking, the interfacial tension between two liquids is difficult to measure, and only few data exist [START_REF] Merkwitz | [END_REF]. The oscillating drop technique [8] is a non contact measurement technique for surface tension measurements of levitated liquid drops. In its original form, it assumes a homogeneous non-viscous drop, free of external forces. In this ideal case, the frequency of surface oscillations is simply related to the surface tension s 0 by Rayleigh's formula [9] :

2 0 0 3 0 0 8 R s w r = (1)
where r 0 is the density of the drop and R 0 its radius. By substituting r 0 R 0 3 = 3M/4p, the apparent density dependence of the frequency disappears which makes this equation particularly easy to use.

The oscillating drop technique can be extended to the measurement of the interfacial tension between two immiscible liquids [10]. Based on the theory of Saffren et al. [START_REF] Saffren | Proceedings of the 2 nd International Colloquium on Drops and Bubbles[END_REF], the theory was worked out for force-free, concentric spherical drops. The geometry considered is summarized in Figure 2. Due to the presence of the interface between liquid L1 and L2, this sytem possesses two fundamental frequencies, driven by the surface tension s 0 and the interfacial tension s 12 .

Adopting the nomenclature of ref [START_REF] Saffren | Proceedings of the 2 nd International Colloquium on Drops and Bubbles[END_REF], the normal mode frequencies w of a concentric, force-free, inviscid compound drop read:

2 W K J w ± ± = (2)
K and J are dimensionless, while W is a frequency squared. W/J is given by:

2 8 0 10 1 (1 ) 2 3 i i W J w t s r t r = + D + D (3)
Here, a number of symbols has been introduced which are defined as follows: w 0 is the unperturbed Rayleigh frequency (eqn (1)) of a simple drop with density r 0 , Radius R 0 and surface tension s 0 (see also Figure 2 for the definition of the symbols).

0 i R R t = (4)
is the square root of the ratio between outer and inner radius,

0 12 s s s = (5)
is the square root of the ratio of the surface tension and the interface tension, and

0 0 3 5 i i r r r r - D = (6)
is the weighted relative density difference between liquids L1 and liquid L2. It remains to write down the expression for K. It is given by:

2 3 3 0 0 3 3 1 1 1 2 4 i i m m m m K s t s t t s t s ± ae ö ae ö = + ± - + ç ÷ ç ÷ è ø è ø (7)
where two additional symbols have been introduced, namely:

5 5 0 3 2 5 5 m t t - = + (8) and 5 5
(1 )

i i i m r t r t - = + D -D (9)
For large s and small Dr i , approximate equations can be derived for the two frequencies w + and w -:

2 2 0 2 4 1 1 w w s t + ae ö = + ç ÷ è ø (10) 6 2 2 1 0 0 2 5 1 3 t w w t s - - ae ö = - ç ÷ è ø (11)
From an experimental point of view it is interesting to discuss the frequencies as a function of the initial, homogeneous composition of the drop. To this end we introduce the relative mass fraction of component 2, i.e. the component with the lower surface tension which will eventually constitute the outer liquid shell. it is given by:

1 3 0 0 1 shell i i rel i m R m m R R r r - ae ö ae ö ç ÷ = = + ç ÷ ç ÷ - è ø è ø (12)
In Figure 3, the frequency spectrum is shown as a function of m rel for parameters corresponding to the Cu-Co system.

Figure 3. The normalized normal mode frequencies w ± /w 0 as a function of the relative mass fraction m rel . For the figure, following parameters were chosen: s 0 =1.3 N/m, s 12 =0.5 N/m, r 0 =7.75 g/cm 3 ,

r i =7.86 g/cm 3 .
Although the oscillations of the inner radius, R i , cannot be observed optically for nontransparent liquid metals, both eigenfrequencies can be determined from the oscillations of the outer radius, R 0 , alone. This is due to the coupling of the two oscillators via the common velocity field in the melt. The relative amplitudes of the oscillations of the outer and inner surface are shown in Figure 4 for both oscillatory modes. The larger the value of |dR 0 /dR i |, the better the detectability. Consequently, the optimal choice to detect both modes, lies between 0.7 < m rel < 0.8.

Results

The experiments were carried out using the TEXUS-EML module during the TEXUS 44 campaign. Two experiments, one on demixing of CuCo, described here, and one on calorimetry and undercooling of an Al-Ni alloy were accommodated. The allotted time span of microgravity for the present experiment was 160 s.

As this time is much too short for undercooling and complete phase separation, it was decided to perform the experiment on a sample which was prepared ex-situ as a two-phase compound drop using a DTA furnace and a melt flux technique which allows deep undercooling and subsequent phase separation of the Cu-Co sample [START_REF] Willnecker | [END_REF]. Of course, such a system is not in equilibrium when it is remelted, but it takes some time to destroy the interface between the two liquids L1 and L2, and this time is sufficient to excite and observe oscillations of the (unstable) interface.

The experiment consisted of three heating cycles:

• one cycle with a completely phase-separated sample

• one cycle with a homogenised sample

• one cycle for maximum undercooling

The experiment was conducted with one sample of the composition Cu 75 Co 25 with a pre-separated microstructure. Careful heating should melt the Cu shell first and then, at higher temperature, the Co core. The aim of the experiment was to observe the oscillations of this separated microstructure in the liquid and to experimentally determine the interface energy of Cu-Co. In a second heating cycle, the microstructure was homogenized and two pulses were applied to observe oscillations of a homogeneous sample for comparison. A third heating cycle was used to investigate growth of a droplet dispersion starting after undercooling at the binodal.

The most important parameter in the preparation of the experiment was the choice of the maximum temperature in the first heating cycle. It had to be chosen such that both, the outer copper shell, and the inner cobalt core are fully molten, but not intermixed. Microstructure analysis of the samples from previous parabolic flights showed that a maximum temperature of 1800°C of the heating cycle was too high, as the pre-separated microstructure has been destroyed. On the other hand, a minimum temperature of about 1500 °C is required to melt the cobalt-rich core. Consequently, a maximum temperature of 1600°C has been chosen for the TEXUS experiment.

The experiment was successful and three heating cycles could be conducted. The second cycle led probably to homogenisation of the liquid sample (T max » 1850°C). Two heating pulses for excitation of the homogeneous droplet oscillations have been applied in the high temperature region. The third cycle led to an undercooling of the melt and a recalescence due to release of latent heat, which is indicated by an arrow in the temperature-time profile in Figure 5. The sample was saved and the experiment with Cu-Co was finished.

Discussion

Temperature Calibration

The emissivity of the sample changes depending on whether or not it is phase separated. The pyrometer data were calibrated for e=0.1, corresponding to a demixed sample. It is assumed that the second heating homogenizes the sample, leading to an emissivity of e=0.13. Therefore, the pyrometer signal had to be corrected according to:

ln 0 1 1 2 2 2 1 1 T T c l e e -= (13)
where l 0 is the operating wavelength of the pyrometer, and c 2 = 1.44 10 4 µm K.

The pyrometer operates in a band of 1.45 -1.8 µm. Assuming an effective wavelength of l 0 = 1.5 µm results in a correction of -2.733 10 -5 K -1 .

Taking this correction into account, the pyrometer signal was recalibrated and is shown in Figure 5. Also shown (dashed line) is the heater control voltage, controlling the heating power in the coil system of the EML module. The sample is molten within 30 s, between 45260 and 45290 s. During cooling, short heater pulses are applied to excite oscillations of the liquid drop. Due to the time resolution of the data acquisition, not all such pulses are shown in Figure 5.

The temperature signal is rather noisy, especially during heating. This is due to sample movement and sample rotation. As explained above, the sample was prepared in a melt flux, and part of this flux was still attached to the sample surface. This flux has a much higher emissivity than the metallic sample. Whenever such a clod of glass entered the measuring spot of the pyrometer, its signal went up, resulting in spikes. In fact, the temporal distance of these spikes is a quantitative measure of the sample's rotation frequency.

The solidus temperature is, according to the phase diagram, T s = 1080 °C and is visible in the signal around 45280 s. The liquidus temperature, T L , of the phaseseparated sample is around 1437 °C, also visible at 45290 s. The liquidus temperature of the homogeneous, single-phase sample is determined as T L = 1357 °C. The binodal temperature is located at T b = 1248 °C and can be recognised around 45350 s. After the final sequence the sample undercooled and solidified at 45410 s, displaying a recalescence peak. Undercooling relative to the corresponding liquidus temperature was about DT = 200 K.

Oscillation Spectra

For the analysis of the spectra, a number of sample parameters need to be known. First of all, the mass was determined before and after the flight. The sample mass before the flight was M 0 = 1.31 g and M ¥ = 1.30 g after the flight, resulting in a small weight loss due to evaporation of dM = 0.01 g, which can be assumed to be mainly copper.

The initial masses of copper and cobalt were M Cu = 1.00566 g, M Co = 0.3064 g, resulting in 76.65 wt% copper. Due to evaporation, the copper content decreased to 76.38 wt% after flight. Therefore, the concentration changed only by 0.27 wt%, which is acceptable.

For the evaluation of the oscillation frequencies, the radius in the liquid phase is required. This cannot be measured directly, and we estimate it from the sample mass according to

3 eff 3M R 4pr = (14)
The densities of liquid copper and cobalt were measured by Saito and coworkers [13,14]. At the melting point, the quoted values are: r Cu (T m )=7.86 g/cm 3 , r Co (T m )=7.75 g/cm 3 . The temperature dependent densities are as follows:

r Co (T) = 9.71 -1.11 10 -3 T g/cm 3 r Cu (T) = 8.75 -0.675 10 -3 T g/cm 3 At T = 2000 K, we obtain r Co (2000 K)=7.49 g/cm 3 and r Cu (2000 K)=7.44 g/cm 3 . As these two densities are very close, we have decided to neglect the density difference and to assume r Co = r Cu = 0.765 r Cu (2000 K) + 0.235 r Co (2000 K) = 7.45 g/cm 3 throughout the analysis. Inserting this value into above equation, we obtain

R eff = R 0 = 3.

mm

We still need to determine m rel and R i . For these two quantities we need to know the compositions of the two separated liquids L1 and L2. This of course depends on the solidification path and is not known a priori. From EDX analysis of samples prepared identically to the flight sample we estimate that the L2 liquid consists of app. 90 wt% copper and 10 wt% cobalt, while L1 is composed of 16 wt% copper and 84 wt% cobalt. We therefore estimate m rel = (1.31) -1 and obtain .

3 i 0 r e l R R 1 m 2 149 mm = - = .
In order to get a feeling for the oscillation frequencies, we need estimates for the surface and interfacial tensions. The surface tensions of the Cu-Co system have been measured by Eichel et al. [15]. For the composition Cu 70 Co 30 which is very close to our sample, their result is:

( ) . . ( )
3 0 N T 1 22 0 29 10 T 1365 C m s - = - × - °
For T = 1665 °C this yields s 0 =1.13 N/m. Inserting this into the Rayleigh equation, eqn

, we obtain a Rayleigh frequency

n 0 = w 0 /(2p) = 27.06 Hz.
For the interfacial tension, we assume complete wetting, yielding s 12 = s L1s L2 .

From ref 15 we have:

( ) . . ( )
3

Surface Tension

As pointed out before, sample oscillations were excited by short current pulses through the heating coil, which led to a compression and subsequent damped oscillations of the sample. The sample shape was recorded by a video camera, looking along the symmetry axis of the sample (top view) operating at 196 Hz.

The obtained images were analysed off-line by image processing with respect to a number of geometrical parameters; the most important ones are: area of the visible cross section and radii in two orthogonal directions. From the latter, two more parameters can be constructed, namely the sum and the difference of these two radii. In case of non-spherical samples, the latter should have slightly different peaks in their oscillation spectra [16], while the Fourier spectrum of the area signal should contain all peaks. Although there were no big differences between the signals, the area signal was used for further analysis. The time signals of these oscillations are shown in Figure 6 for the first melting cycle. In the first cycle, three oscillations are clearly visible, but the first one is somewhat disturbed. The second cycle also shows three oscillations; they are not shown here. In order to obtain the oscillation frequencies, each oscillation was analysed separately by performing a Fourier transformation. The result is shown in Figure 7 for all pulses analysed. Except for the first pulse of the first cycle, all spectra display a single peak around 28 Hz. The first pulse of the first cycle displays two peaks at 28 Hz, and a small peak around 15 Hz. Positions and corresponding temperatures of the main peaks are shown in Table 1. Assuming that, after the first pulse, the sample is single-phase, these frequencies correspond to the Rayleigh frequency, eqn(1). We then obtain the surface tension as a function of temperature, as shown in Figure 8. Linear fit to the data yields

( ) . . ( ) / 4 T 1 29 2 7710 T 1357 C N m s - = - - ° (15)
This is in excellent agreement with the data measured by Eichel [15].

As is evident from Figure 6 and Figure 7, the oscillations during the first pulse of the first cycle are more complex than for the other pulses. We have therefore analysed this pulse in greater detail, as shown Figure 9. Regardless of the parameter analysed, two peaks around 29 Hz and 28 Hz and a small peak at 15 Hz are clearly visible. Therefore, we conclude that the liquid drop was initially phase separated, giving rise to two peaks around 15 Hz and 29 Hz, and homogenized in the course of the oscillations yielding the Rayleigh frequency at 28 Hz. If this is correct, we must be able to fit all three frequencies by two values for the surface tension s 0 and the interfacial tension s 12 . This is shown in Table 2. From the fit we obtain:

Pulse

s 0 = 1.21 N/m, s 12 = 0.17 N/m

The value for the surface tension corresponds to 1590 °C and agrees well with the fit obtained from the other pulses, see Figure 8. The value of the interfacial tension is somewhat lower than previously estimated. This may be due to a slight shift in the compositions of the two liquids L 1 and L

Summary

Using the EML module on board the TEXUS 44 microgravity mission, a Co 25 Cu 75 sample was successfully processed. Following results were obtained:

• surface tension as function of temperature • interfacial tension at 1590 °C • size distribution of precipitated Co drops The interfacial tension could not be measured as a function of temperature because the unstable interface was destroyed during the first pulse. The final and decisive experiment will have to be performed on board the ISS, when time is sufficient to keep the sample in the undercooled phase until complete phase separation is obtained and a metastable interface exists between the two liquid phases.

Figure 1 .

 1 Figure 1. Phase diagram of Cu-Co showing the metastable miscibility gap. Symbols indicate experimentally determined liquidus and binodal temperatures.

Figure 2 .

 2 Figure 2. Cross section of a spherical, concentric compound drop consisting of two immiscible liquids with densities r i and r 0 , radii R 0 and R i , surface tension of the outer liquid s 0 , and interfacial tension s 12 .

Figure 4 .

 4 Figure 4. Relative amplitudes of the oscillations of inner and outer surface as a function of mass fraction for both modes.

Figure 5 .

 5 Figure 5. Temperature-time profile of the Cu-Co TEXUS 44 experiment. Dotted lines show the heater activity, not all pulses are shown due to the time resolution of the display. The arrow indicates final solidification.

  two-phase drop.

Figure 6 .

 6 Figure 6. Oscillations of the visible cross section during the first melting cycle.

Figure 7 .

 7 Figure 7. Fourier transforms of the area signal for all evaluated pulses. The spectra are shifted vertically for clarity. From bottom to top: cycle1/pulse 1, cycle 1/pulse 2, cycle 1/pulse 3, cycle 2/pulse 1, cycle 2/pulse 2.

Figure 8 .

 8 Figure 8. Surface tension of Cu 75 Co 25 alloy.

Figure 9 .

 9 Figure 9. Fourier spectra of the 1 st pulse in the 1 st cycle. FFT of cross section (top) and radius sum (bottom) is shown. Spectra are shifted vertically for clarity.

Table 1 .

 1 Temperatures and peak positions of the pulsed oscillations.

		Temperature	Frequency	Remarks
		°C	Hz
	cycle 1			split peak
	pulse 1	1590	(28,6)	(28,1+29,06)/2
	cycle 1
	pulse 2	1490	28,7
	cycle 1
	pulse 3	1410	28,8
	cycle 2
	pulse 0	1750	27,8
	cycle 2
	pulse 1	1660	28,0
	cycle 2
	pulse 2	1570	28,3

Table 2 .

 2 2 . Measured and calculated frequencies for the first pulse of the first cycle.

		measured	calculated
	n 0	28.1	28.0
	n +	29.1	29.1
	n -	15.5	15.4

Acknowledgements

Our sincere thanks go to the EADS team in Bremen and Friedrichshafen, to the launch team at Esrange, and, last but not least, to the DLR-MUSC team for their continuous and excellent support. We also would like to thank ESA for providing this flight opportunity. Without their help, this experiment would not have been possible.