Antlers, frontal view. A , Alces alces has short beams and a horizontal palmation plane with a pronounced upper concavity; B , Cervalces has long beams and a vertical palmation plane with a light posterior concavity (reconstruction based on C . latifrons remains from several German localities). 

Contexts in source publication

Context 1

... (1988), Caloi and Palombo (1995), and Valli and Palombo (2005) agree in suggesting that, in deer, the development of these tubercles is not indicative of diet. Regarding the ectostylid, it is worth noting, that in those molars in which the ectostylid is well developed (mainly in Cervalces ), the distal wing of the protoconid is remodelled forming a groove beneath it (Breda, 2001b). This grove has been wrongly interpreted by Azzaroli (1952:134) as “ traces of Paleomeryx fold ” (Breda, 2001a) but its relationship to the ectolstylid is clear because it is deeper in those teeth in which the ectostylid is more developed (mainly m1) and disappears toward the occlusal surface (which the ectostylid does not reach), being more evident in worn teeth (again mainly m1). Given that the presence/absence of this groove, both in Alces and Cervalces , depends on the presence/absence and development of the entostylid (it can be interpreted as a remodelling of the tooth wall to give place to the ectostylid itself), it does not have a functional meaning by itself and so it does not suggest dietary adaptations. The living moose, compared to Eurasian Cervalces , has a reduced span of antlers, because of the shortening of the beam (Lister, 1993a). Moreover, the palmation plane is vertical and has a light posterior concavity in C . gallicus – C . latifrons , whereas it is horizontal with a pronounced upper concavity in A . alces (Fig. 7) (Breda, 2001b; Breda and Marchetti, 2005). Antlers are very plastic structures dependent on sexual selection and varying many times in the same evolutionary lineage. Probably Eurasian Cervalces antlers were too wide and heavy to be used as defen- sive or aggressive weapons, so they could be interpreted as display organs. Gould (1973; 1974) suggests that Megaloceros giganteus , because of the huge weight and lateral extension of its antlers, was not able to wave its head laterally as other deer with palmated antlers (living moose included) do. Moreover, the wide span of its antlers was visible in frontal view as it was in Cervalces because of the vertical orientation of the palmations (Breda, 2001b). The display function could explain why in the evolution of the lineage of Cervalces the development of antlers was not positively allometric as it was in M . giganteus and as it usually is in large sized deer (Gould, 1974; Clutton-Brock et al., 1980; Clutton-Brock, 1982). In the transition from C . gallicus to C . latifrons , the vast increase in size (about one and a half, Lister, 1987) is not followed by an isometric increase of antlers. That is, the lateral span is kept roughly the same (about 2.0 – 2.5 m) but the palmate portion enlarges giving a stronger visual impact (Breda, 2001b). An isometric (or, even more dramatically, a positively allometric) development of antlers with respect to body size, would have been disadvantageous for biomechanical reasons, so the palmation enlarged in medial direction by shortening the beam, rather than in lateral direction. This enlargement of the palmation over the beam length is extremely valuable in terms of weight and energy saving, because the palmation requires less compact bone than the tines or the beam. Moreover, the ...

Context 2

... of the palmation plane from C . gallicus to C . latifrons , which increases the frontal outline without increasing the surface and so the weight (Breda, 2001b), could further support the hypothesis of a display function of antlers. The display function would better play its role in an open environment. Regarding M . giganteus , some authors (e.g., Clutton-Brock, 1982) argued with Gould ’ s (1974) hypothesis that such massive antlers, so expensive in energetic terms and so disadvantageous for their owners given their weight and their overall dimensions, could have evolved only for display. Kitchner (1987), in particular, maintains that the giant deer antlers were used for fighting as in other deer and suggests the way in which they would have been used during combats. This author (Kitchner, 1987) acknowledges Gould ’ s (1974) idea that, in the giant deer, locking the palmation tines would have been an inefficient way of fighting, given their slightly backward orientation, but shows that, by tucking the head between the front legs, the males could have locked their antlers just above the second tine. In this position, the palmed brow tine project down in front of the eyes protecting them from injury, and, moreover, this more medial interlock would have reduced the bending moment acting on the antler s during pushing, and so the risk of breaking them (Kitchner, 1987). As in red deer, pushing and twisting would have knocked the opponent off balance and its neck and shoulders would have been gored by the terminal tines of the winner (Kitchner, 1987). Kitchner (1987) further supports his fighting hypothesis, describing how the beam cross-section, in M . giganteus , is elliptical with the major axis parallel to the force that acts on the antlers in fighting, and how the hydroxyapatite crystals are differently ori- ented around the beam to better resist the forces of fighting. Kitchner ’ s (1987) study for the giant deer is very persuasive, but it cannot be applied to the Eurasian Cervalces . As a matter of fact, the antlers of the Eurasian Cervalces could interlock only on the palmation tines (other tines being absent). It means that only males of the same antler size could have locked their antlers in order to wrestle. It is difficult but still possible to imagine an interlock in C . latifrons , because of its quite flat palmation and tines, but in C . gallicus the backward concave palmation results in slightly backward pointing tines (like the palmation tines of M . giganteus ) that could not have locked at all. However, also in C . latifrons , other problems arise, because locking antlers at such a distance from the head would have given a strong bending moment that would probably have broken the antlers. Moreover, if the palmation tines were engaged in the locking, which tines could have been used to gore the opponent? Would Cervalces have been the only large deer lacking a brow tine to protect its eyes during intra-specific combats? Studies on the hydroxyapatite crystals have not been carried out in Cervalces , but the cross-section of its beam does not ap- pear to be adapted to resist the strength of wrestling. It is slightly elliptical close to the burr with the long axis parallel to the frontal bone (perpendicular to the direction of the force and so little resistant), then it is circular for most of the beam length, and it becomes elliptical again approaching the palmation with the long axis perpendicular to the frontal bone (parallel to the direction of the force). If it is very unlikely that the Eurasian Cervalces used its antlers for fighting, this cannot be ruled out for the North American C . scotti , whose very peculiar antler structure (see Scott, 1885 and Churcher and Pinsof, 1987 for a description) could have been used in fighting in about the same way as in living A . alces . The wide span of Cervalces antlers led many authors (e.g., Lister, 1987, 1993a) to think that this genus lived in a more open environment than A . alces , because its antlers would have hampered its movements in a wooded habitat. Lister (1994) reports that in the forest, large North American A . alces males do have difficulty manoeuvring their broad, palmated, and multi-tined antlers. But, as mentioned above, the present confinement of living moose to dense taiga is mainly due to human presence. Therefore, it is here suggested that the natural habitat of A . alces , a more open taiga with scattered conifers, could have been habitable also for Cervalces . Lister (1994) records a variation in the antler length and orientation of M . giganteus , suggesting that shorter and more upright antlers occurred in interglacial wooded conditions of the Holsteinian and Eemian, whereas longer and more outspread antlers occurred in the largely open habitat of the Irish Late- glacial. Such an idea of different antler length in different envi- ronmental conditions, has been proposed by Soergel (1912) for C . latifrons as well. The German author suggested a difference between the typical large specimens of C . latifrons from S ü ␤ enborn and Mosbach p.p., with long beams and associated with an open environment fauna, and some smaller specimens from Mauer and Mosbach p.p., associated with a woodland fauna and that he supposed to have shorter beams. Schmidt (1934), Erdbrink (1954), Wernert (1957), and Kahlke (1990) accepted the existence of these two forms of C . latifrons , but, as Kahlke (1990) admitted, no antler remains from Mauer were recorded up to then. Finally, Breda (2001a) recorded two antler beams from Mauer (SMNK Qp 1240 and Qp 1590, ex Freudenberg collection), broken before the beginning of the palmation but long enough to deny Soergel ’ s (1912) hypothesis. The length of the beams from the burr to the point at which they are broken (shorter than the actual beam lengths) is respectively 305 and 260 mm; the circumference above the burr is respectively 189 and 142 mm. Plotting these measures in the dispersion graph of Breda and Marchetti (2005:fig. 7), they prove longer nonetheless than part of the antlers from S ü ␤ enborn. This suggests that, as living moose, also Cervalces could live in a variety of environments, with closer or more open arboreal cover. The occipital bone is wider and shallower in Cervalces than in the living genus (Azzaroli, 1979). However, this is a quite variable feature even at intra-specific level because the development of the nuchal crest (and thus the occipital bone width), which provides insertion to the powerful neck muscles, varies with head weight and thus with antler size (Breda, 2001b). Hence, strong A . alces males with massive antlers may have a quite large occiput and, on the contrary, Cervalces females and young males may have a relatively narrow occiput. Thus, the different width of the occipital bone is here considered only as a consequence of the different antler size. Scott (1885) states that the neck of the C . scotti from New Jersey was shorter than that of A . alces . The only Eurasian Cervalces preserving the cervical vertebra is the C . gallicus holotype from S é n è ze. Azzaroli (1952), in describing the mounted skeleton from S é n è ze, states that Cervalces had a longer neck than present-day Alces , whereas, Breda (2001a; 2005) points out that the cervical vertebrae are assembled too far apart from one another and lined up on a nearly vertical axis. So, even keeping the uncertainty arising from the very bad preservation of this specimen, probably, C . gallicus neck was not longer than that of A . alces . As already suggested by Scott (1885), the short neck and the long legs of Cervalces prevented it from reaching the ground to graze and so it should have been a browser like its living relative. Geist (1999) states that the neural spines were shorter and thinner in C . scotti than in living Alces and suggests (Geist, 1999: 247) that “ . . . the relatively short neural spines indicate that there was little twisting, wrestling and lifting. ” Due to the lack of fossil record, we cannot argue if this was true for the Eurasian species of Cervalces . However, if confirmed, this would strengthen the hypothesis that the antlers were not used ...