Estimating physical characteristics of neonate Myotragus balearicus (Artiodactyla, Caprinae)

Myotragus balearicus BATE, 1909 is a fossil dwarf bovid endemic to the Gymnesic Islands (Mallorca, Menorca and surrounding islets, Western Mediterranean Sea); it became extinct more than 4,000 years ago. Its neonate body dimensions have been studied comparing them with some extant neonate bovids. The small size of the adult specimens (shoulder height about 45-50 cm) is one of the most peculiar features displayed by Myotragus balearicus. From the identified neonate leg bones coming from three caves of Mallorca (Cova des Moro, Cova Estreta and Cova de Son Maiol) and one cave of Menorca (Cova C-2), an estimated shoulder height of 18 cm has been obtained for the Late Pleistocene neonate Myotragus. The difference in length of the bones of Pleistocene and Holocene Myotragus, being slightly more than 20 % shorter the latter, gives a shoulder height of 15 cm for Holocene neonates. The neonate Myotragus height was less than half the mother’s shoulder height. This proportion differs substantially from the recorded ratio for the extant bovids. An estimated weight of 700-900 g for Late Pleistocene Myotragus balearicus neonates have been approached from similar body sized mammals. The small ratio (about 2%) between neonate and adult weight in Myotragus balearicus agrees with a suiform pattern, in a clear contrast to the typical ruminant pattern (where neonate weight is usually > 4%). Our estimate of the neonate size has been checked through the study of the dimensions of the birth canal in adult females.