Natural selection in isolated environments led to the positive selection of species bearing an ex... more Natural selection in isolated environments led to the positive selection of species bearing an extraordinary array of morphological traits and a very high grade of endemism. The unbalanced mammal assemblage found in the Upper Miocene karst infillings of the Gargano Peninsula (southern Italy), and especially the intriguing ruminant Hoplitomeryx, is one of the best examples of fast, isolated evolution. Hoplitomeryx exhibits a peculiar combination of craniodental and postcranial characters, some of which are unique among the other ruminant families. For this reason, its phylo-genetic position is still puzzling and far from being clarified. Thus, every contribution to a more comprehensive knowledge of the genus is crucial to better understand the evolutionary process that led to such an advanced and peculiarly adapted ruminant. Here we report newly discovered dentognathic remains from the Gargano Peninsula, which are attributed to six different species of Hoplitomeryx on the basis of mo...
American journal of physical anthropology, Jan 25, 2018
High-resolution imaging of fossils with X-ray computed microtomography (μCT) has become a very po... more High-resolution imaging of fossils with X-ray computed microtomography (μCT) has become a very powerful tool in paleontological research. However, fossilized bone, embedding matrix, and dental tissues do not always provide a distinct structural signal with X-rays. We demonstrate the benefits of high-resolution neutron radiation in three different specimens showing problematic contrasts with X-ray μCT. We compare neutron with X-ray μCT scans of fossils from two Miocene catarrhines from the Vallès-Penedès Basin: the cranium (IPS58443.1, holotype) of the putative stem hominoid Pliobates cataloniae, to discriminate between bone and matrix; and two lower molars (IPS1724n,o, holotype) of Barberapithecus huerzeleri, to discriminate among dental tissues. X-ray μCT scans of these specimens fail to retrieve any contrast between matrix/bone and enamel/dentine, whereas neutron μCT scans deliver high-contrast images, enabling a proper evaluation of the specimens' internal anatomy. Low bone/m...
Phylogenetic relationships among extinct hominoids (apes and humans) are controversial due to per... more Phylogenetic relationships among extinct hominoids (apes and humans) are controversial due to pervasive homoplasy and the incompleteness of the fossil record. The bony labyrinth might contribute to this debate, as it displays strong phylogenetic signal among other mammals. However, the potential of the vestibular apparatus for phylogenetic reconstruction among fossil apes remains understudied. Here we test and quantify the phylogenetic signal embedded in the vestibular morphology of extant anthropoids (monkeys, apes and humans) and two extinct apes (Oreopithecus and Australopithecus) as captured by a deformation-based 3D geometric morphometric analysis. We also reconstruct the ancestral morphology of various hominoid clades based on phylogenetically-informed maximum likelihood methods. Besides revealing strong phylogenetic signal in the vestibule and enabling the proposal of potential synapomorphies for various hominoid clades, our results confirm the relevance of vestibular morphol...
Natural selection in isolated environments led to the positive selection of species bearing an ex... more Natural selection in isolated environments led to the positive selection of species bearing an extraordinary array of morphological traits and a very high grade of endemism. The unbalanced mammal assemblage found in the Upper Miocene karst infillings of the Gargano Peninsula (southern Italy), and especially the intriguing ruminant Hoplitomeryx, is one of the best examples of fast, isolated evolution. Hoplitomeryx exhibits a peculiar combination of craniodental and postcranial characters, some of which are unique among the other ruminant families. For this reason, its phylo-genetic position is still puzzling and far from being clarified. Thus, every contribution to a more comprehensive knowledge of the genus is crucial to better understand the evolutionary process that led to such an advanced and peculiarly adapted ruminant. Here we report newly discovered dentognathic remains from the Gargano Peninsula, which are attributed to six different species of Hoplitomeryx on the basis of mo...
American journal of physical anthropology, Jan 25, 2018
High-resolution imaging of fossils with X-ray computed microtomography (μCT) has become a very po... more High-resolution imaging of fossils with X-ray computed microtomography (μCT) has become a very powerful tool in paleontological research. However, fossilized bone, embedding matrix, and dental tissues do not always provide a distinct structural signal with X-rays. We demonstrate the benefits of high-resolution neutron radiation in three different specimens showing problematic contrasts with X-ray μCT. We compare neutron with X-ray μCT scans of fossils from two Miocene catarrhines from the Vallès-Penedès Basin: the cranium (IPS58443.1, holotype) of the putative stem hominoid Pliobates cataloniae, to discriminate between bone and matrix; and two lower molars (IPS1724n,o, holotype) of Barberapithecus huerzeleri, to discriminate among dental tissues. X-ray μCT scans of these specimens fail to retrieve any contrast between matrix/bone and enamel/dentine, whereas neutron μCT scans deliver high-contrast images, enabling a proper evaluation of the specimens' internal anatomy. Low bone/m...
Phylogenetic relationships among extinct hominoids (apes and humans) are controversial due to per... more Phylogenetic relationships among extinct hominoids (apes and humans) are controversial due to pervasive homoplasy and the incompleteness of the fossil record. The bony labyrinth might contribute to this debate, as it displays strong phylogenetic signal among other mammals. However, the potential of the vestibular apparatus for phylogenetic reconstruction among fossil apes remains understudied. Here we test and quantify the phylogenetic signal embedded in the vestibular morphology of extant anthropoids (monkeys, apes and humans) and two extinct apes (Oreopithecus and Australopithecus) as captured by a deformation-based 3D geometric morphometric analysis. We also reconstruct the ancestral morphology of various hominoid clades based on phylogenetically-informed maximum likelihood methods. Besides revealing strong phylogenetic signal in the vestibule and enabling the proposal of potential synapomorphies for various hominoid clades, our results confirm the relevance of vestibular morphol...
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Papers by Alessandro Urciuoli