Reinforcing the idea of an early dispersal of Hippopotamus amphibius in Europe: Restoration and multidisciplinary study of the skull from the Middle Pleistocene of Cava Montanari (Rome, central Italy).

A skull of Hippopotamus recovered from the area of Tor di Quinto, within the urban area of Rome (central Italy) is here redescribed. Despite being one of the most complete specimens of hippopotamuses of the European Pleistocene, the Tor di Quinto skull did not attract much research interest, due to long-standing uncertainties on its provenance. This work begun in 2021, when the skull was restored, within a large renovation project on the vertebrate exposed at the Earth Science University Museum of Sapienza University of Rome. Original sediments were found inside the cranial and mandible cavities during the restoration work, which were sampled for petrographic analyses. By combining a review of the old paleontological, archeological and geological literature published during the 19th and 20th century on the Rome basin and the correlation of these new sedimentological and petrographic information with the lithostratigraphic and synthemic units of the national geological cartography, we clarify that the Hippopotamus skull was most likely to have been collected from a quarry called Cava Montanari, from a formation dated between 560 and 460 ka. Morphological and biometric analyses clearly support an attribution of the Cava Montanari specimen to the extant species Hippopotamus amphibius. The reassessment of the stratigraphic and geological data on Cava Montanari implies that the studied specimen is the earliest confirmed occurrence of Hippopotamus amphibius in the European fossil record.

Stratigraphic reassessment of Grotta Romanelli sheds light on Middle-Late Pleistocene palaeoenvironments and human settling in the Mediterranean.

During the last century, Grotta Romanelli (Southern Italy) has been a reference site for the European Late Pleistocene stratigraphy, due to its geomorphological setting and archaeological and palaeontological content. The beginning of the sedimentation inside the cave was attributed to the Last Interglacial (MISs 5e) and the oldest unearthed evidence of human occupation, including remains of hearths, was therefore referred to the Middle Palaeolithic. Recent surveys and excavations produced new U/Th dates, palaeoenvironmental interpretation and a litho-, morpho- and chrono-stratigraphical reassessment, placing the oldest human frequentation of the cave between MIS 9 and MIS 7, therefore embracing Glacial and Interglacial cycles. These new data provide evidence that the sea reached the cave during the Middle Pleistocene and human occupation occurred long before MISs 5e and persisted beyond the Pleistocene- Holocene boundary.

A Middle Pleistocene wolf from central Italy provides insights on the first occurrence of Canis lupus in Europe.

Here, we describe a partial cranium of a large canid dated at 406.5 ± 2.4 ka from the Middle Pleistocene of Ponte Galeria (Rome, Italy). The sample represents one of the few Middle Pleistocene remains of a wolf-like canid falling within the timeframe when the Canis mosbachensis-Canis lupus transition occurred, a key moment to understand the spread of the extant wolf (Canis lupus) in Europe. CT-based methods allow studying the outer and inner cranial anatomy (brain and frontal sinuses) of a selected sample of fossil and extant canids. Morphological and biometric results allowed to: (I) ascribe the cranium from Ponte Galeria to an adult Canis lupus, representing the first reliable occurrence of this taxon in Europe; (II) provide the content for a biochronological revision of the Middle Pleistocene record of European wolves.

The origin of early Acheulean expansion in Europe 700 ka ago: new findings at Notarchirico (Italy).

Notarchirico (Southern Italy) has yielded the earliest evidence of Acheulean settlement in Italy and four older occupation levels have recently been unearthed, including one with bifaces, extending the roots of the Acheulean in Italy even further back in time. New 40Ar/39Ar on tephras and ESR dates on bleached quartz securely and accurately place these occupations between 695 and 670 ka (MIS 17), penecontemporaneous with the Moulin-Quignon and la Noira sites (France). These new data demonstrate a very rapid expansion of shared traditions over Western Europe during a period of highly variable climatic conditions, including interglacial and glacial episodes, between 670 and 650 (i.e., MIS17/MIS16 transition). The diversity of tools and activities observed in these three sites shows that Western Europe was populated by adaptable hominins during this time. These conclusions question the existence of refuge areas during intense glacial stages and raise questions concerning understudied migration pathways, such as the Sicilian route.

Old African fossils provide new evidence for the origin of the American crocodiles.

Molecular and morphological phylogenies concur in indicating that the African lineages formerly referred to Crocodylus niloticus are the sister taxon the four Neotropical crocodiles (Crocodylus intermedius, C. moreleti, C. acutus and C. rhombifer), implying a transoceanic dispersal from Africa to America. So far the fossil record did not contribute to identify a possible African forerunner of the Neotropical species but, curiously, the oldest remains referred to the African C. niloticus are Quaternary in age, whereas the oldest American fossils of Crocodylus are older, being dated to the early Pliocene, suggesting that another species could be involved. We re-described, also thanks to CT imaging, the only well-preserved topotipic skull of Crocodylus checchiai Maccagno, 1947 from the late Miocene (Messinian) African site of As Sahabi in Libya. As previously suggested on the basis of late Miocene material from Tanzania, C. checchiai is a valid, diagnosable species. According to our phylogenetic analyses, C. checchiai is related to the Neotropical taxa and could be even located at the base of their radiation, therefore representing the missing link between the African and the American lineages.

First report of Sus strozzii (Suidae, Mammalia) from the Early Pleistocene of Hungary (Dunaalmás) and species distinction based on deciduous teeth.

Herein we describe a fragment of a mandible with a deciduous fourth premolar (dp4) from the Early Pleistocene locality of Dunaalmás, representing the first confirmed report of Sus strozzii from Hungary. The comparison of dp4 measurements supports a statistically significant distinction between S. strozzii and Sus scrofa. The two species overlap in time during the late Early Pleistocene of Europe (Epivillafranchian), but suid remains of this time-span are seldom classified at a species level. The correct taxonomic identification of the Epivillafranchian suids, which are often associated with evidences of hominin presence, is of great palaeoenvironmental value because S. scrofa and S. strozzii possess different ecological requirements.

The Late Pleistocene European badger Meles meles from Grotta Laceduzza (Brindisi, Apulia, Southern Italy): the analysis of the morphological and biometric variability.

In the last decades, many studies have focused on the description of fossil badger materials from Eurasia and several evolutionary hypotheses have been proposed. Nevertheless, the debate on taxonomy of the Late Villafranchian-Aurelian European badgers is still far from being solved and several species/subspecies were established over time. Herein, we described for the first time the craniodental and postcranial remains of Meles meles from Grotta Laceduzza (Apulia, Southern Italy), representing the largest sample of this taxon in the European Pleistocene record. Morphological and morphometric comparisons with fossils coming from the European Pleistocene sites were carried out; morphometric data were also compared with those of several extant populations of the European badger. The results of this work suggest that the badger fossil remains from the Mediterranean region can be considered as an ecomorphotype of this highly polymorphic species, showing a great morphological and morphometric variability throughout its wide geographical range. This variability is mainly expressed in some craniodental features and body size and could reflect local ecological adaptations, also linked to glacial/interglacial cycles.

MicroWeaR: A new R package for dental microwear analysis.

Mastication of dietary items with different mechanical properties leaves distinctive microscopic marks on the surface of tooth enamel. The inspection of such marks (dental microwear analysis) is informative about the dietary habitus in fossil as well as in modern species. Dental microwear analysis relies on the morphology, abundance, direction, and distribution of these microscopic marks. We present a new freely available software implementation, MicroWeaR, that, compared to traditional dental microwear tools, allows more rapid, observer error free, and inexpensive quantification and classification of all the microscopic marks (also including for the first time different subtypes of scars). Classification parameters and graphical rendering of the output are fully settable by the user. MicroWeaR includes functions to (a) sample the marks, (b) classify features into categories as pits or scratches and then into their respective subcategories (large pits, coarse scratches, etc.), (c) generate an output table with summary information, and (d) obtain a visual surface-map where marks are highlighted. We provide a tutorial to reproduce the steps required to perform microwear analysis and to test tool functionalities. Then, we present two case studies to illustrate how MicroWeaR works. The first regards a Miocene great ape obtained from through environmental scanning electron microscope, and other a Pleistocene cervid acquired by a stereomicroscope.

Synchrotron radiation reveals the identity of the large felid from Monte Argentario (Early Pleistocene, Italy).

We describe here a partial skull with associated mandible of a large felid from Monte Argentario, Italy (Early Pleistocene; ~1.5 million years). Propagation x-ray phase-contrast synchrotron microtomography of the specimen, still partially embedded in the rock matrix, allows ascribing it reliably to Acinonyx pardinensis, one of the most intriguing extinct carnivorans of the Old World Plio-Pleistocene. The analysis of images and 3D models obtained through synchrotron microtomography - here applied for the first time on a Plio-Pleistocene carnivoran - reveals a mosaic of cheetah-like and Panthera-like features, with the latter justifying previous attributions of the fossil to the extinct Eurasian jaguar Panthera gombaszoegensis. Similarly, we reassign to A. pardinensis some other Italian materials previously referred to P. gombaszoegensis (sites of Pietrafitta and Ellera di Corciano). The recognition of Panthera-like characters in A. pardinensis leads to reconsidering the ecological role of this species, whose hunting strategy was likely to be different from those of the living cheetah. Furthermore, we hypothesise that the high intraspecific variation in body size in A. pardinensis can be the result of sexual dimorphism, as observed today in all large-sized felids.

Phylogenetic and functional implications of the ear region anatomy of Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina.

Several detailed studies of the external morphology of the ear region in extinct sloths have been published in the past few decades, and this anatomical region has proved extremely helpful in elucidating the phylogenetic relationships among the members of this mammalian clade. Few studies of the inner ear anatomy in these peculiar animals were conducted historically, but these are increasing in number in recent years, in both the extinct and extant representatives, due to wider access to CT-scanning facilities, which allow non-destructive access to internal morphologies. In the present study, we analyze the extinct ground sloth Glossotherium robustum and provide a description of the external features of the ear region and the endocranial side of the petrosal bone, coupled with the first data on the anatomy of the bony labyrinth. Some features observable in the ear region of G. robustum (e.g., the shape and size of the entotympanic bone and the morphology of the posteromedial surface of the petrosal) are highly variable, both intraspecifically and intraindividually. The form of the bony labyrinth of G. robustum is also described, providing the first data from this anatomical region for the family Mylodontidae. The anatomy of the bony labyrinth of the genus Glossotherium is here compared at the level of the superorder Xenarthra, including all available extant and extinct representatives, using geometric morphometric methods. In light of the new data, we discuss the evolution of inner ear anatomy in the xenarthran clade, and most particularly in sloths, considering the influence of phylogeny, allometry, and physiology on the shape of this highly informative region of the skull. These analyses show that the inner ear of Glossotherium more closely resembles that of the extant anteaters, and to a lesser extent those of the giant ground sloth Megatherium and euphractine armadillos, than those of the extant sloths Bradypus and Choloepus, further demonstrating the striking morphological convergence between the two extant sloth genera.

A revision of hominin fossil teeth from Fontana Ranuccio (Middle Pleistocene, Anagni, Frosinone, Italy).

The Fontana Ranuccio hominin teeth (FR, Latium, Italy) are dated to the Middle Pleistocene. In previous studies these teeth were classified as two lower (left and right) second molars, one lower left central incisor and a badly worn incisor crown, the exact position of which could not be determined. In 2012 these remains were acquired by the Anthropological Service of S.B.A.L. (Italian Ministry of Culture) and for this reason re-analysed. In a thorough revision we have reassessed them both morphologically and dimensionally as two lower (left and right) first molars, one lower left lateral incisor and a possible upper left canine. The comparison with penecontemporaneous and diachronic samples shows that the Fontana Ranuccio teeth are morphologically similar to Atapuerca-Sima de los Huesos, Arago XIII and Neanderthal samples.

CT scanning analysis of Megantereon whitei (Carnivora, Machairodontinae) from Monte Argentario (Early Pleistocene, central Italy): evidence of atavistic teeth.

CT scanning analysis applied to vertebrate palaeontology is providing an increasing number of data of great interest. This method can be used in many branches of palaeontology such as the investigation of all the fossilized elements in a hard matrix and the hidden structures in the bones. A large number of pathologies are "hidden", completely or partially invisible on the external surface of the bones because their development took place within the bones. However, the study of these diseases and abnormalities plays a crucial role in our understanding of evolutionary and adaptive processes of extinct taxa. The analysis of a partial skeleton of the sabre-toothed felid Megantereon whitei from the Early Pleistocene karst filling deposits of Monte Argentario (Tuscany, Italy) has been carried out. The CT scanning analysis put in evidence the presence of supernumerary teeth (P(2)) and the absence of P3 in the mandible. The occurrence of P(2) can be considered as an evidence of atavism. Such an archaic feature is recorded for the first time in Megantereon.

A pathological Late Pleistocene canid from San Sidero (Italy): implications for social- and feeding-behaviour.

Evidence of diseases on vertebrate fossil bones can provide detailed information on many aspects of extinct animals. This study focused on pathological craniodental remains (left maxilla and dentary) referred to the canid Cuon alpinus unearthed from a Late Pleistocene karst filling deposit at San Sidero (Apulia, southern Italy). These fossils show clear evidence of a chronic periodontitis that caused the animal's death. Clinical diagnosis of the disease and the timing of its development have been defined on the basis of a veterinary odontostomatology approach, in addition to radiographic and tomographic techniques. From the initiation of the infection until death, a time span of at least 6 months occurred, and three main steps have been defined: (1) the bacterial infections of the buccal cavity turning into severe periodontitis, (2) the fracture of the lower carnassial and (3) the loss of teeth due to the worsening infection that deformed and/or eroded maxillary and mandibular bones and enlarged alveoli. The analysis of the palaeopathology also provides information about the biomechanics of the bite, on the feeding behaviour and on the relationships of injured members in a pack of Late Pleistocene canids.

Evidence of earliest human occurrence in Europe: the site of Pirro Nord (Southern Italy).

Some flint lithic artifacts were discovered in the fissure fillings of the well-known Pirro Nord site (Apulia, Southern Italy). The lithic industry, composed by three cores and some flakes, has been found to be associated to an Early Pleistocene vertebrate fossil assemblage. The fossil association contains a wide range of micromammals, including Allophaiomys ruffoi and Episoriculus gibberodon and large mammals including Bison degiulii and Equus altidens together with African elements as the gelada baboon Theropithecus and the saber-toothed cat Megantereon whitei. It defines the latest Villafranchian chronological unit (Pirro Nord Faunal Unit) in the Western European mammal biochronology. The lithic industry of Pirro Nord represents the oldest occurrence of the genus Homo in Europe as it is attributable to a chronological interval between 1.3 and 1.7 Ma. This supports the hypothesis that the genus Homo, with Oldowaian technology, extended its range in Europe, probably from western Asia, during the first half of the Early Pleistocene. The new discovery from Pirro Nord changes the chronology of the first arrival of hominids in Europe and offers new perspectives in the debate about the human dispersal in the Early Pleistocene.