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Elephas tiliensis n. sp. from Tilos island (Dodecanese, Greece)

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... In the following years, several research expeditions were made by teams of the University of Athens, often in collaboration with the Natural History Museum of Vienna. The systematic excavations in the cave yielded several thousands of fossils, mainly of elephants, but also of deer in the deeper layers, as well as of tortoises (Symeonidis 1973;Symeonidis et al. 1973;Bachmayer and Symeonidis 1975b;Bachmayer et al. 1976Bachmayer et al. , 1984Theodorou 1983;Symeonidis 1994, 2001;Theodorou et al. 2007;Mitsopoulou et al. 2015). The material from Tilos is curated at AMPG and MNHW. ...
... ★Palaeoloxodon tiliensis (Theodorou, Symeonidis and Stathopoulou, 2007) Taxonomic and Nomenclatural History The elephant sample from Charkadió was initially (Symeonidis 1973) referred to two distinct subspecies, originally defined on material from Malta, the smaller Palaeoloxodon antiquus falconeri (Busk, 1867) and the larger P. antiquus melitensis (Falconer, 1862). In the same year, the identification was changed in part, by referring the material to P. a. falconeri and P. a. mnaidriensis Adams, 1874 ). ...
... A new species was erected for the Tilos dwarf elephant much later, classified in the extant genus Elephas (E. tiliensis; Theodorou et al. 2007). ...
Chapter
Several Aegean islands are known for their Pleistocene endemic mammal species. In isolation from the mainland, these mammals adapted to insular environments evolving unique characters. Only flying animals (birds, bats, insects) and animals that are capable of long-distance overseas traveling—by swimming, rafting, or floating—managed to successfully colonize the islands. Crete, the largest Greek island, had the richest endemic fauna. It has been isolated from the mainland since roughly five million years ago. Most mammals endemic to Crete did not survive into the Holocene, but went extinct before. Only the Cretan shrew is a surviving relict of the Pleistocene fauna. All native Cretan mammals today are feral descendants of introduced species. The review here of the fossil record of Crete shows the presence of 17 species of endemic mammals, consisting of dwarf elephants and mammoths, dwarf hippos, several species of deer (varying in size from dwarf deer to giant deer), giant mice, an otter, and the Cretan shrew. These taxa are distributed from the Early Pleistocene until the late Late Pleistocene, and their fossils mainly originate from coastal localities. The most biodiverse of these localities is Liko Cave, west of Réthymnon on the northern coast. The peak in taxonomic diversity is noted during the Late Pleistocene, when the large herbivores consisted of at least eight species of deer and a dwarf elephant. The majority of Pleistocene Cretan species follow the “island rule,” with the Cretan dwarf mammoth (Mammuthus creticus) at the extreme end of the trend toward dwarfism, weighing a mere 4% of the body mass of its mainland relative, M. meridionalis, and the Cretan rat (Kritimys catreus) at the extreme end toward gigantism, being about 6.7 times larger than its mainland relative, Praomys. The notorious exception is shown by the Cretan deer, Candiacervus, which instead evolved a spectacular adaptive radiation into eight species. Close to Crete are Kárpathos and Kassos. These islands were united during large periods of the Middle and Late Pleistocene, and harbored four endemic species: one elephant, two deer, and a mouse. The elephant (Palaeoloxodon aff. creutzburgi) evolved a size reduction similar to that of the Cretan elephant, in accordance with the “island rule.” The Karpathos deer belong to two species and are probably the result of in situ speciation. On Tilos, an older deer fauna was replaced by a younger elephant fauna. These elephants (P. tiliensis) show a significant degree of dwarfism (approx. 9% of the body mass of its mainland relative). Fossils of elephants have also been discovered on Rhodes, Naxos, Astypálaea, and Delos, which are all dwarf forms of the mainland species P. antiquus. The presence of fossil elephants has further been reported from Kýthnos, Sériphos, Milos, and Paros. The presence of fossil deer finally has been also reported from Amorgós and Rhodes.
... Since the finds are usually scanty, their taxonomic identity is not always clear. The currently generally accepted endemic elephant species in the Eastern Mediterranean region, after more than a century of palaeontological research, are the following: Mammuthus creticus (Bate, 1907) and Palaeoloxodon creutzburgi (Kuss, 1965) on Crete, Palaeoloxodon lomolinoi van der Geer et al., 2014 on the central Cyclades, Palaeoloxodon tiliensis (Theodorou et al., 2007) on Tilos, and Palaeoloxodon cypriotes (Bate, 1903) and Palaeoloxodon xylophagou Athanassiou et al., 2015 on Cyprus (Theodorou, 1986;Poulakakis et al., 2002;Theodorou et al., 2007;van der Geer et al., 2014;Athanassiou et al., 2015;Sen, 2017). In the following subsections we present previously undescribed specimens and comment on elephant samples that were previously considered to represent endemic populations or for which taxonomic attribution is uncertain. ...
... Since the finds are usually scanty, their taxonomic identity is not always clear. The currently generally accepted endemic elephant species in the Eastern Mediterranean region, after more than a century of palaeontological research, are the following: Mammuthus creticus (Bate, 1907) and Palaeoloxodon creutzburgi (Kuss, 1965) on Crete, Palaeoloxodon lomolinoi van der Geer et al., 2014 on the central Cyclades, Palaeoloxodon tiliensis (Theodorou et al., 2007) on Tilos, and Palaeoloxodon cypriotes (Bate, 1903) and Palaeoloxodon xylophagou Athanassiou et al., 2015 on Cyprus (Theodorou, 1986;Poulakakis et al., 2002;Theodorou et al., 2007;van der Geer et al., 2014;Athanassiou et al., 2015;Sen, 2017). In the following subsections we present previously undescribed specimens and comment on elephant samples that were previously considered to represent endemic populations or for which taxonomic attribution is uncertain. ...
... In the following subsections we present previously undescribed specimens and comment on elephant samples that were previously considered to represent endemic populations or for which taxonomic attribution is uncertain. We refrain from describing and discussing in detail samples that have been repeatedly described in previous studies of the Eastern Mediterranean insular elephants, referring the reader to the relevant publications (Bate, 1905(Bate, , 1907Theodorou, 1983;Mol et al., 1996;Poulakakis et al., 2002;Theodorou et al., 2007;Herridge, 2010;van der Geer et al., 2010van der Geer et al., , 2014Herridge and Lister, 2012;Sen et al., 2014;Athanassiou et al., 2015;Sen, 2017), unless we deem an update necessary. ...
Article
The Eastern Mediterranean islands, most of which belong to the Aegean archipelago, have a complex biogeographic history, which puts its stamp on their fauna and flora. A now extinct but most important faunal component, in terms of geographic spread and taxonomic diversity, are the elephants. The Eastern Mediterranean islands are particularly rich in Pleistocene endemic elephant localities, which preserve samples of extinct endemic populations. These were either descendants of the European straight-tusked elephant Palaeoloxodon antiquus or the Southern mammoth, Mammuthus meridionalis. Their presence, history and palaeobiogeography has been documented only for Cyprus, Crete, Kasos, Rhodes, Tilos, Kýthera, Naxos, and Delos. For six other islands only anecdotal references exist in the literature: K alymnos, Astyp alaia, Milos, S eriphos, Kýthnos and Paros. Here, we provide an update on previously published specimens and taxa, describe previously undescribed specimens that were relocated in museum collections, as well as recently excavated specimens, and put these in the context of island palaeobiogeography. We conclude that dwarf elephants, endemic to their palaeo-island, lived on the islands of palaeo-Cyclades, Astyp alaia, Crete, KasoseK arpathoseSaría, Tilos, Rhodes and Cyprus, whereas the elephants from Kephallenía, K alymnos and Kýthera are indistinguishable on the species level from mainland Palaeoloxodon antiquus. Elephant fossils of unresolved taxonomic status are reported from five present-day islands. The Eastern Mediterranean endemic elephants likely derived from separate and independent colonisation events from the mainland. No island supported more than one proboscidean species at any time. We found that isolation had no effect on the degree of dwarfism, but that there exists a threshold of about 6e10 km distance between the island and the mainland, below which no dwarfism evolved, likely as a result of genetic contact with the mainland population. We also found that although island area is correlated with the degree of dwarfism in elephants, other factors, such as the level of interspecific competition, may limit this degree.
... On the other hand, the excellent preservation of fossil bones from Tilos provided identifiable skeletal remains belonging to Palaeoloxodon tiliensis n.sp. (Mitsopoulou et al. 2015), previously known as Elephas tiliensis (Theodorou et al. 2007). Thus, poorly and exceptionally preserved fossils are equally represented in this study. ...
... In 1971, Symeonidis found a very rich endemic fauna in Charkadio cave (Symeonidis 1972). Since then, the continuous research directed towards the recognition of a new dwarf elephant species originally named Elephas tiliensis (Theodorou et al. 2007) and later attributed to Palaeoloxodon (Mitsopoulou et al. 2015). This elephant is considered to be the last in Europe, while its appearance on the cave ranges from 45,000 to 4000-3500 years BP (Mitsopoulou et al. 2015;Stathopoulou and Theodorou 2001;Theodorou et al. 2007). ...
... Since then, the continuous research directed towards the recognition of a new dwarf elephant species originally named Elephas tiliensis (Theodorou et al. 2007) and later attributed to Palaeoloxodon (Mitsopoulou et al. 2015). This elephant is considered to be the last in Europe, while its appearance on the cave ranges from 45,000 to 4000-3500 years BP (Mitsopoulou et al. 2015;Stathopoulou and Theodorou 2001;Theodorou et al. 2007). The fauna from Charcadio cave also includes deer (140,000 years old), chelonia, aves and micromammals (Bachmayer et al. 1976;Symeonidis 1972;Theodorou 1983;Theodorou 1988). ...
Article
The present study concerns the histological description of fossilized mammalian bone behavior, under the effect of hydrogen peroxide, acetic acid, and formic acid. These reagents have been applied on such material for decades, mainly for matrix removal and surface cleaning. The material used includes fossil bone parts from two different fossiliferous sites in Greece, Charkadio Cave on Tilos Island (Dodecanese) and Kerassia (Euboea Island). In order to conclude on the extent of histological damage on fossilized bone by the different chemicals and discuss their optimum application on bone, numerous experiments were realized. In each of these, samples from both sites were exposed to different combinations of parameters such as the type and concentration of reagents and the duration of exposure. The methodology applied included the detailed observation of bone histology under a scanning electron microscope (SEM), as well as qualitative chemical analyses through X-ray microanalysis (EDS) and mineralogical analyses by X-ray diffraction (XRD) when needed. pH measurements were collected during each subsequent stage of the experiment. All samples underwent density and porosity measurements before and after treatment. In conclusion, the results of this study confirmed that the initial state of preservation is the determinant factor when deciding upon the conservation strategy to be followed and the type and concentration of the applied chemical on fossilized skeletal remains. Also, it became evident that high concentrations of acetic and formic acid tend to deteriorate the microstructure of fossils and thus render any histological study impossible.
... In Greece, the use of computer-aided visualization techniques have been applied only recently in the field of vertebrate palaeontology (Lyras, 2009;Provatidis et al., 2011;Polydoras et al., 2014;Theodorou et al., 2014). In the current study, skeletal remains of the insular dwarf elephant Palaeoloxodon tiliensis (Theodorou et al., 2007) from the island of Tilos (Dodecanese, Greece) are visualized with the use of 3D visualization techniques and fabricated by Rapid Prototyping technologies, known as 3D printing, for the first time. Objectives are the accurate digitization of the morphology with the use of both CT scan and surface Laser Scanning, the 3D modeling of the digital data, the mathematical manipulation of the dimensions of the skeletal elements taking into account taphonomical data and allometry, and finally the 3D printing of anatomically and metrically accurate skeletal elements. ...
... It is one of the best known localities in the Eastern Mediterranean with remains of Pleistocene to Holocene insular dwarf elephants, as well as remains of reptiles, birds, and deer. Excavations in Charkadio Cave have been carried out since 1971 (Symeonidis, 1972;Theodorou et al., 2007). Early excavations focused on the eastern border of the cave and resulted in an 8.5 m deep section, aiming at the clarification of the stratigraphy of the cave sediments. ...
... Subsequently, a thorough biometric study revealed that the observed two size groups correspond to male and female individuals of a single endemic species (Theodorou, 1983). In 2007, this species was named Elephas tiliensis Theodorou et al., 2007. In the current study the species is referred to as Palaeoloxodon tiliensis in accordance to the prevailing opinion that Palaeoloxodon is a valid genus and that Mediterranean endemic proboscideans derived from a Palaeoloxodon antiquus ancestor, as supported by morphological traits (Shoshani and Tassy, 2005;Shoshani et al., 2007;Ferretti, 2008;Herridge, 2010). ...
Article
Charkadio Cave, on Tilos Island, is one of the richest Mediterranean fossiliferous sites, preserving remains of the dwarf elephant Palaeoloxodon tiliensis. This species is considered to be the last European elephant. Recent advances in the fields of engineering and imaging technology and their applications in palaeontology have allowed the digitization, modelling and 3D printing of skeletal remains of P. tiliensis for the first time. Taphonomical data were combined with appropriate mathematical methods and allometric analyses in order to determine missing bone measurements and estimate correct relative proportions of skeletal elements. Computed Tomography and non-contact digitization via Laser Scanning were used in order to capture the specimens' surface morphology and create 3D models that are adjusted to the correct dimensions derived from the mathematical analyses. The 3D models were then 3D printed with the use of Rapid Prototyping technologies. A research potential of fossil 3D modeling could be its application in morphological comparisons between different taxa. In this study, atlas 3D models of P. tiliensis and Palaeoloxodon antiquus (Falconer and Cautley, 1847) have been combined in a single 3D model that quantifies morphological differences by a color scale, thus minimizing observation error. 3D models and 3D printed replicas facilitate and enhance inter-institutional scientific interaction, minimizing costs and risks related to the transfer of irreplaceable fossil specimens. Finally, a positive outcome related to the above research could be its application in educational activities hosted in institutes such as schools, universities and museums.
... In Greece, the use of computer-aided visualization techniques have been applied only recently in the field of vertebrate palaeontology (Lyras, 2009;Provatidis et al., 2011;Polydoras et al., 2014;Theodorou et al., 2014). In the current study, skeletal remains of the insular dwarf elephant Palaeoloxodon tiliensis (Theodorou et al., 2007) from the island of Tilos (Dodecanese, Greece) are visualized with the use of 3D visualization techniques and fabricated by Rapid Prototyping technologies, known as 3D printing, for the first time. Objectives are the accurate digitization of the morphology with the use of both CT scan and surface Laser Scanning, the 3D modeling of the digital data, the mathematical manipulation of the dimensions of the skeletal elements taking into account taphonomical data and allometry, and finally the 3D printing of anatomically and metrically accurate skeletal elements. ...
... It is one of the best known localities in the Eastern Mediterranean with remains of Pleistocene to Holocene insular dwarf elephants, as well as remains of reptiles, birds, and deer. Excavations in Charkadio Cave have been carried out since 1971 (Symeonidis, 1972;Theodorou et al., 2007). Early excavations focused on the eastern border of the cave and resulted in an 8.5 m deep section, aiming at the clarification of the stratigraphy of the cave sediments. ...
... Subsequently, a thorough biometric study revealed that the observed two size groups correspond to male and female individuals of a single endemic species (Theodorou, 1983). In 2007, this species was named Elephas tiliensis Theodorou et al., 2007. In the current study the species is referred to as Palaeoloxodon tiliensis in accordance to the prevailing opinion that Palaeoloxodon is a valid genus and that Mediterranean endemic proboscideans derived from a Palaeoloxodon antiquus ancestor, as supported by morphological traits (Shoshani and Tassy, 2005;Shoshani et al., 2007;Ferretti, 2008;Herridge, 2010). ...
... The ex is tence was first confirmed in 2005, when a unique el e phant skull was ex ca vated by the Na tional Kapoditstrian Uni ver sity of Ath ens in collab o ra tion with the Geo log i cal Sur vey of Cy prus on the Xylofagou coast (Theodorou et al., 2005). The ma te rial from Xylofagou and Aetocremnos is com pa ra ble with the di mensions of E. tiliensis Theodorou et al., 2007b, con firm ing the ex is tence of at least two Pleis to cene el e phant pop u la tions on Cy prus (Theodorou et al., 2007a). The Agia Napa el e phant re mains from the Phanourios mi nor site are too frag men tary to prove the ex is tence of the larger el e phant spe cies. ...
... Up to now, there is no di rect ev i dence for a hu man pres ence on Cy prus dur ing the Late Pleis to cene. Dur ing the ex ca va tions that took place at Agia Napa, on the east ern side of Cy prus, a well-preserved par tial skull and some ex trem i ties of an en demic genet, Genetta plesictoides (Bate, 1903) were ex ca vated from the un dis turbed Phanourios mi nor lay ers, dated at 13,500-11,000 years (Theodorou et al., 2007b). Ge nets could not have mi grated by swim ming to Cy prus as el e phants or hip pos did. ...
Article
Full-text available
In 2005, numerous vertebrate tracks were discovered in carbonate aeolianites in and around the town of Paphos, in the southwestern part of Cyprus. The main track-bearing exposure is located in a protected archaeological site near the Agia Solomoni Church inside the city of Paphos, where cross-sections through tracks are abundant in vertical exposures of the aeolianite along Apostolou Pavlou Avenue. Some exposures show as many as 10 tracks per m2 of vertical exposure. Several additional tracks were found in the extensive subterranean tomb complex, the Tombs of the Kings, just outside Paphos. The aeolian deposit was formed when westerly to south- westerly winds drove fine- to medium-grained calcareous sand onshore from the beach. This generated low coastal dunes, represented by 1-2-m-thick, cross-bedded sets made up of grainflow and wind-ripple strata, and sand sheets composed entirely of wind-ripple strata. The sediment does not yet have an absolute date, but is conside- red to be of Late Pleistocene to Early Holocene age, as are many other coastal aeolianites in the Mediterranean area. The Late Pleistocene endemic fauna in Cyprus was limited to the dwarf hippopotamus Phanourios minor Desmarest, 1822, the dwarf elephant Elephas cypriotes Bate, 1902, a small carnivore Genetta plesictoides Bate, 1903, and (possibly) humans. The exposed tracks are 5-15 cm in diameter, with a few tracks up to 23 cm in size. This range of size correlates well with the estimated foot size of dwarf hippopotami and dwarf elephants. This low-diversity, endemic island fauna provides a unique opportunity to correlate tracks with trackmakers.
... The Zourida and Gerani caves are especially important for specimens of the endemic Cretan tortoise Testudo marginata cretensis Bachmayer, Brinkerink and Symeonidis, 1975. Indeterminate probable testudinid material has been discovered in Kandilia Cave on Karpathos island in the southern Aegean (Kuss, 1975), and in Charkadio Cave on the Dodecanese island of Tilos, the latter dating from between 4500-3500 years before present (Theodorou et al., 2007). On mainland Greece, Pleistocene fossils attributed to Testudo sp., Testudo marginata Schoepff, 1793, and Testudo graeca have been reported from Psychiko near Athens (Bachmayer and Symeonidis, 1970), Lakonia in the Peloponnese (Schleich, 1982), Xerias in eastern Macedonia , and Petralona Cave in Chalikidiki (Table 1); Petralona additionally manifests a large-bodied tortoise of uncertain affinities (Kretzoi and Poulianos, 1981). ...
... Interestingly, the current Cretan Testudo population is thought to have been introduced by humans, perhaps for food (Lymberakis and Poulakakis, 2010). Indeed, butchering might explain the unusual taphonomic accumulations of tortoise limb bones in other latest Pleistocene-Holocene cave assemblages around the Aegean (e.g., Charkadio on Tilos; Theodorou et al., 2007); note that isolated turtle limb elements similarly dominate Pleistocene-Holocene middens in other island settings (e.g., Vanuatu; White et al., 2010). ...
Article
Turtle remains are common in the Miocene-Holocene deposits of Greece, and are a key focus of the growing research interest in Neogene herpetofaunas from the Aegean region. Some of the most important finds include one of Europe's stratigraphically youngest pleurodiran taxa, Nostimochelone lampra, from the Early Miocene of Macedonia, together with arguably the richest record of fossil tortoises from the Eastern Mediterranean. This incorporates the presently oldest definitive representatives of the quintessential genus Testudo sensu stricto from the Late Miocene of Attica and Macedonia, and numerous specimens of the colossal (carapace ∼2 m-length) testudinid Cheirogaster from Late Miocene-Late Pliocene sediments in southern and northern Greece, as well as on the eastern Aegean islands of Samos and Lesvos. Tantalising, but as yet unconfirmed Miocene accounts of the geoemydid Mauremys in Macedonia, and indeterminate emydid-like remains from Euboea, also provide potentially significant range extensions. Although hampered by a historically sparse documentation, the fossil turtles of Greece are a significant resource that record both assemblage changes and the origin of modern lineages.
... (ii) Rates of evolution are known to be greatly accelerated on islands, so that fossils of large insular P. antiquus are less likely to be represented: dwarfism may evolve rapidly in a so-called tachytelic stage (spanning the order of millennia), followed by a second stage of slower, but ultimately much more pronounced size change [22,53,86,87]; see also quantitative dwarfing models of [68,[88][89][90]). It is also pertinent to note that on numerous other islands with abundant endemic palaeoloxodont fossil records, the ancestral P. antiquus has also often not been retrieved (Table 1.2 in [8,91]). ...
... Thus, the larger males and smaller females of sexually size-dimorphic insular elephants have on several occasions been misdiagnosed as belonging to separate species, as happened for example with the Charkadio Cave assemblage on Tilos (e.g. [91] vs. [104]). The opposite is also a cause for confusion, with multiple species being conflated with single, sexually dimorphic species (as has for example happened with remains from Luparello Fissure, Sicily, see p. in 87 [66] vs. [8]). ...
Article
Full-text available
The phenomenon of insular dwarfism in proboscideans is particularly well represented on the Siculo-Maltese Palaeoarchipelago, an island group on which a species complex of palaeoloxodont elephants evolved during the Middle-Late Pleistocene. This likely included three species from Malta, four from Sicily (and possibly its palaeo-islands), and one from Favignana Island, ranging in size from the 1 m-tall Palaeoloxodon falconeri to continental-sized 4m-tall P. antiquus. However, our understanding of the causes for extreme differences in body size among insular samples in such a small geographic region is still limited. Here, I document the full range in size of elephants from the palaeoarchipelago, and discuss the reasons for size differences on the three islands in time and space in relation to predation, competition, resource limitation, accelerated life history, and duration of isolation. Differences in size between larger and smaller Sicilian elephants from Luparello Fissure, as well as possibly also in P. ex gr. P. mnaidriensis from Puntali Cave, San Teodoro Cave, and Favignana Island, may relate to the duration of isolation, or alternatively environmental stressors associated with the Last Glacial Maximum in the case of the Favignana elephant. Additionally, small but significant differences in size observable in Middle Pleistocene P. ex gr. P. falconeri from different localities on Sicily, as well as in Maltese P. ‘melitensis’ may also relate to duration of isolation, highlighting the need for better geochronological data in order to better distinguish macro-ecological causes driving body size change from more subtle effects relating to duration of isolation.
... The ex is tence was first confirmed in 2005, when a unique el e phant skull was ex ca vated by the Na tional Kapoditstrian Uni ver sity of Ath ens in collab o ra tion with the Geo log i cal Sur vey of Cy prus on the Xylofagou coast (Theodorou et al., 2005). The ma te rial from Xylofagou and Aetocremnos is com pa ra ble with the di mensions of E. tiliensis Theodorou et al., 2007b, con firm ing the ex is tence of at least two Pleis to cene el e phant pop u la tions on Cy prus (Theodorou et al., 2007a). The Agia Napa el e phant re mains from the Phanourios mi nor site are too frag men tary to prove the ex is tence of the larger el e phant spe cies. ...
... Up to now, there is no di rect ev i dence for a hu man pres ence on Cy prus dur ing the Late Pleis to cene. Dur ing the ex ca va tions that took place at Agia Napa, on the east ern side of Cy prus, a well-preserved par tial skull and some ex trem i ties of an en demic genet, Genetta plesictoides (Bate, 1903) were ex ca vated from the un dis turbed Phanourios mi nor lay ers, dated at 13,500-11,000 years (Theodorou et al., 2007b). Ge nets could not have mi grated by swim ming to Cy prus as el e phants or hip pos did. ...
... Endemic elephants, variously reduced in size, have been reported from a number of Mediterranean islands. Most of the species originated from the mainland species Palaeoloxodon antiquus (e.g., dwarf straight-tusked elephants from Siculo-Maltese archipelago, Crete, Tilos, Rhodos, palaeo-Cyclades, Cyprus) (see, e.g., Ambrosetti, 1968;Athanassiou et al., 2015;Ferretti, 2008;Herridge, 2010;Herridge and Lister, 2012;Mangano and Bonfiglio, 2012;Masseti, 2006;Palombo, 2004Palombo, , 2010Poulakakis et al., 2002;Theodorou et al., 2007;Sen et al., 2014;Van der Geer et al., 2010, 2014. Conversely, in the Mediterranean islands, few dwarf mammoth remains have been reported, and those only in the oldest Pleistocene fauna of Crete (Mammuthus creticus), and in the youngest Pleistocene fauna of Sardinia (Mammuthus lamarmorai) (Herridge and Lister, 2012;Palombo et al., 2012). ...
... On the other hand, the distal portion of the Alghero tibia differs from that of Palaeoloxodon ex gr. P. mnaidriensis from Puntali cave (Sicily) (Ferretti, 2008), in which the inferior outline of the distal epiphysis is more sinuous with a more robust, rounded medial malleolus, features that are respectively more and less pronounced in Palaeoloxodon tiliensis (Theodorou et al., 2007) and P. antiquus (Fig. 4). ...
Article
Full-text available
Endemic elephants, variously reduced in size, have been reported from a number of Mediterranean islands. Most of these originated from the mainland species Palaeoloxodon antiquus. A few dwarf mammoth remains are recorded from Crete and Sardinia. In Sardinia, a largely incomplete skeleton and a few mammoth teeth have been reported from localities believed to range in age from the late middle to the late Pleistocene. The chronology of colonisation by the ancestral species, the actual persistence through time of Mammuthus lamarmorai on the island, and the morphological and dimensional range of the species are, however, poorly known. This research aims to describe a distal portion of a left tibia of a dwarf elephant found in the Alghero area (NW Sardinia), showing some morphological traits and dimensions consistent with those of the endemic Sardinian mammoth (Mammuthus lamarmorai). The main unanswered questions about chronology, colonisation and population dynamics of endemic Sardinian elephants are highlighted and briefly discussed.
... In addition, total bone length (TL: from most proximal end of lateral tuberosity to most distal end of lateral condyle) and diaphyseal length (DL: between proximal and distal epiphyseal lines, taken on anterior surface) were collected for adult humeri of P. falconeri from Spinagallo Cave, Sicily (UCat; n ¼ 7), Palaeoloxodon tiliensis, a medium-sized (approx. 810 kg) dwarf Palaeoloxodon from Charkadio Cave, Tilos [22] (UoA; n ¼ 6) and M. lamarmorai from Sardinia (MSNF). 'Adult' is here defined as those bones with fused distal epiphyses. ...
... Mammuthus creticus molars are wider than, but similar in length and crown height to, those of P. falconeri and P. cypriotes (table 1), resulting in a tooth that is larger overall, though significantly different only from P. falconeri ( figure 2a). The M. creticus adult humerus falls within, or just above, the upper range of P. falconeri for TL and DL, respectively, and well below the range of P. tiliensis (the next largest dwarf Palaeoloxodon species after P. falconeri and P. cypriotes [22]) for both DL and TL (table 3). This suggests a body size closer to P. falconeri (shoulder height: approximately 1 m; mass: approximately 240 kg) than P. tiliensis (1.5 m; approximately 810 kg), which is similar in size to M. exilis and M. lamarmorai (table 3). ...
Article
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The insular dwarfism seen in Pleistocene elephants has come to epitomize the island rule; yet our understanding of this phenomenon is hampered by poor taxonomy. For Mediterranean dwarf elephants, where the most extreme cases of insular dwarfism are observed, a key systematic question remains unresolved: are all taxa phyletic dwarfs of a single mainland species Palaeoloxodon antiquus (straight-tusked elephant), or are some referable to Mammuthus (mammoths)? Ancient DNA and geochronological evidence have been used to support a Mammuthus origin for the Cretan 'Palaeoloxodon' creticus, but these studies have been shown to be flawed. On the basis of existing collections and recent field discoveries, we present new, morphological evidence for the taxonomic status of 'P'. creticus, and show that it is indeed a mammoth, most probably derived from Early Pleistocene Mammuthus meridionalis or possibly Late Pliocene Mammuthus rumanus. We also show that Mammuthus creticus is smaller than other known insular dwarf mammoths, and is similar in size to the smallest dwarf Palaeoloxodon species from Sicily and Malta, making it the smallest mammoth species known to have existed. These findings indicate that extreme insular dwarfism has evolved to a similar degree independently in two elephant lineages.
... Previously referred to as two distinct forms, the Tilian elephants are now considered as belonging to a single species with marked dimorphism. This form, however, has been only recently specifically described as Elephas tiliensis by Theodorou, Symeonidis, and Stathopoulou (2007), previously described from Sicily and Malta (Vaufrey 1929;Ambrosetti 1968). The proboscidean of Tilos is slightly larger than the Sicilian pygmy elephant, whilst the age of the deposits of the discovery site range from the very late Pleistocene to the Holocene (Symeonidis et al. 1973;Bachmayer and Symeonidis 1975;Bachmayer et al. 1976;Dermitzakis and Sondaar 1978;Theodorou 1983Theodorou , 1988. ...
... According to Symeonidis (1972) and Theodorou and Agiadi (2001), it appears that the species first appeared in the sediment of the Charkadio Cave about 45,000 years BP and became extinct almost 4,000-3,500 years ago. Relating to different parts of the cave, the more recent of these datings appear to prove the simultaneous existence of the Tilian elephants and post-Palaeolithic man (Bachmayer and Symeonidis 1975;Bachmayer et al. 1976, MASSETI: ANCIENT EXPLORATIONS OF THE MEDITERRANEAN 11 FIGURE 8. Artist's reconstruction of the extinct dwarf elephant, Elephas tiliensis Theodorou, Symeonidis, and Stathopoulou, 2007, of Late Pleistocene-Holocene Tilos, adapted from the osteological material in the Museum of Megalochorio (Tilos, Greece), and compared to the size of its supposed ancestor E. antiquus Falconer and Cautley, 1847 (drawing by Alessando Mangione and Marco Masseti). Bachmayer et al. 1984;Theodorou and Symeonidis, 2001). ...
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sailing the wine-dark sea to men of alien language…" (Homer, The Odyssey, I: 183) When there were no geographical maps, when the marine routes were still uncertain, the ships unsafe and the oceans wild and dangerous, travelling was an epic endeavour. The explorers of antiquity almost always departed without knowing exactly where they were going, generally heading for exot-ic seascapes populated in their imagination by fabulous creatures (Fig. 1). The three books of the Odyssey between the ninth and the twelfth are considered to be the oldest of the poem. Here Odysseus recounts the vicis-situdes of his travels before the council of the Phaeacians, King Alcinous and his wife, Arete. His account embodies perfectly the attitude of the man of the ancient world towards travel and exploration. These are adventures dominated by the Olympic and supernatural, where Odysseus and his companions find themselves tackling the most arduous exploits, in the cavern of Polyphemus, between the rock and the whirlpool of Scylla and Charybdis or before the enchanted palace of Circe. Together with the episodes of the cattle of Helios, the overhanging rocks, the winds of Aeolus and the Sirens, the adventures recounted by Odysseus undoubtedly have disparate origins in folklore and in the most ancient heroic cycles, such as that of the Argonauts (Codino 1974). Nevertheless, the journey that Homer's hero tells the king and queen of the Phaeacians about was undertaken in a relatively recent period, when the main sea routes of the Mediterranean were already known and codified, despite what the king of Ithaca wishes us to believe. Effectively, Homerian critics date the definitive ver-sion of the two epic poems — the Iliad and the Odyssey — to the seventh century BC. The same critics maintain that what are considered the most recent books of the Odyssey, in terms of lan-guage and style, describe a post-Mycenaean world coinciding with the centuries of darkness of the so-called Dark Age of Greece (1200–800 BC) (cf. James 1991). The routes along which Odysseus must have sailed had been mapped out many millennia earlier by intrepid sailors who explored the FIGURE 1. The image of a striped dolphin, Stenella ceruleoalba (Mayen, 1833), in the decoration of a Late Helladic I blade referred to about 1500 BC (Athens, National Museum). This cetacean seems to be the species of dolphin most frequent-ly represented in Aegean Bronze Age art.
... Palaeoloxodon "mnaidriensis" disappeared on Sicily around 32 ka (Bonfiglio et al., 2008), on Crete a population slightly reduced in size has been claimed to be present during the LGM, ca. 18 ka or later (¼"Palaeoloxodon chaniensis" in Symeonides et al., 2001), dwarf elephants have been supposed to have survived on Cyprus to the end of the Pleistocene ca.11e10 ka (Reese, 1999), and on Tilos Palaeoloxon tiliensis persisted during the Holocene, maybe to about 3.5 ka Theodorou et al., 2007), roughly the same time during which the latest M. primigenius inhabited Wrangel Island (Vartanyan et al., 2008). ...
Article
A rich Upper Paleolithic iconography testifies to a long coexistence of humans and Mammuthus primigenius during the last glacial in most of Europe, including northern Spain, and supplies additional information for a better understanding of the dispersion and last occurrence of woolly mammoths in southernmost Europe (i.e. in the Iberian and Italian peninsulas) during this time. In Italy, where the scanty M. primigenius findings are likely not younger than 38 ka (except for the Gravettian remains from the Arene Candide cave, eastern Liguria), no representations of woolly mammoths have been reported to date. An exception is the carved mammoth objects (a few Gravettian ornaments and female figurines), recorded in Ligurian sites, but the hypothesis that they could have been imported from some distant area cannot be ruled out. Conversely, in Spain along the northern Atlantic coast, M. primigenius remains have been found in some sites yielding mammoth representations. In southern Spain, where M. primigenius was present in the Padul basin (Granada) during most of MIS 3 (between 40.4 and 30.6 cal ka BP), artistic representations of woolly mammoths are unknown. As regard to Palaeoloxodon, some populations were present during the late MIS 3 in the Iberian Peninsula as in Western Europe, whereas no sound data support the persistence of straight-tusked elephants on mainland during MIS 2. Therefore, whether the intriguing elephant painting of the Spanish El Castillo cave could represent a straight-tusked elephant – suggesting a survival of the species in Northern Spain during the Last Glacial Maximum – or an unusual representation of a woolly mammoth, still remains an unanswered question.
... One of the most important co-occurrences of turtles and proboscideans is that of the Charkadio cave in Tilos Island. Along with many findings of dwarf elephants (Elephas tiliensis, see Theodorou et al., 2007), the preliminary study of the material revealed several postcranial remains of a small testudinid taxon (see Bachmayer and Symeonidis, 1975). The complete absence of shell remains raised questions of possible human interaction in the cave, but recent studies do not support this claim (see Michailidis et al., this volume). ...
... The current view on the distribution of insular dwarf elephants is that every island harbours its own endemic species (Doukas and Athanassiou, 2003) as already suggested earlier (Sondaar, 1977;Dermitzakis and Sondaar, 1978;Theodorou, 1983;Theodorou et al., 2007). Species can thus not be shared by two islands unless these islands were connected to each other previously during periods of low sea-level and the period of isolation since the break-up of the islands was insufficient for speciation. ...
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During the Late Pleistocene, Naxos and adjacent areas, including Delos and Paros, constituted a mega-island, here referred to as palaeo-Cyclades. The extensive low-lying plains with lakes and rivers provided a suitable habitat for elephants. Due to long-term isolation from the mainland and mainland populations, these elephants evolved miniature size. The species found on Naxos had a body size of about ten percent of that of the mainland ancestor, Palaeoloxodon antiquus. During the glacial periods of the Late Pleistocene, P. antiquus may have migrated eastwards and southwards in search of better conditions and reached the islands. The dwarf species of the various Southern Aegean islands (e.g. Crete, Tilos, Rhodos, palaeo-Cyclades) are each the result of independent colonisation events. The very small size of the Naxos species respective to the dwarf elephants from Crete is explained as due to the lack of competitors. The only other elements of the contemporaneous fauna were a rock mouse (Apodemus cf. mystacinus) and a shrew (Crocidura sp.). Submergence of the area, climate change, volcanism, hunting by humans or a combination of these factors during the terminal Pleistocene may have caused the extinction of this endemic fauna.
... The finds indicate an animal quite larger than P. cypriotes, of a size comparable to that of Tilos elephant, P. tiliensis (Theodorou et al., 2007b). ...
... Notably, both the right and left zygopodials (ulna and radius) are fused (Figs. 9 and 10). This feature, possibly representing a locomotory adaptation, occurs rather frequently among small-sized insular elephant species, as Palaeoloxodon falconeri (Ambrosetti, 1968) and Palaeoloxodon mnaidriensis (Ferretti, 2008) from Sicily, but not in Palaeoloxodon tiliensis, whose size is only a bit larger than that of P. falconeri (Theodorou, 1983; Theodorou et al., 2007) and is rather rare among large-sized continental taxa (Palombo et al., 2010). As discussed below, the Morimenta elephant shows a different degree of size reduction from both Sicilian P. " mnaidriensis " and P. falconeri. ...
Article
The Gonnesa Quaternary deposits have been cited since the end of the 19th century due to the discovery, during the construction of a railway, of an incomplete postcranial skeleton belonging to an endemic dwarfed elephant, afterward described by Major as a new species (“Elephas lamarmorae”Major, 1883). Although the remains have since been reported in the literature as coming from the aeolian deposits outcropping at Funtana Morimenta, the precise provenance of the findings and their chronostratigraphical setting remained uncertain. Taking into account the route of the now disused railway, the stratigraphical successions of the Morimenta area, and the fact that the elephant bones were actually collected during a number of excavations spanning several decades, the location of the fossiliferous site is most likely on the northeast end slope of Guardia Pisano hill (Gonnesa), where aeolianites correlate with the Funtana Morimenta Formation (FMF) outcrop. The FMF is supposed to predate the onset of the MIS 5e climatic event and the Tyrrhenian “Panchina” overlies equivalent deposits cropping out along the Gonnesa Gulf coast. Therefore, the hypothesis that the elephant remains found in the “Morimenta” area were retrieved from late Middle Pleistocene deposits cannot be ruled out. The anatomical features of the bones suggest they represent a single individual, perhaps partially exposed and damaged before the discovery. New evidence, including a thus far unpublished tusk fragment from the Guardia Pisano hill (Gonnesa), whose Schreger angles fall within the range of Mammuthus, supports the systematic attribution of the incomplete Morimenta skeleton to a dwarfed mammoth. The size reduction of this Sardinian dwarfed mammoth is discussed in light of body-mass changes undergone by insular endemic elephants.
... phant that was endemic to the Greek island Tilos, which is merely 65 km 2(Theodorou et al., 2007), and Santa Catarina's guinea pig, Cavia intermedia, which is endemic to a single island of only 10 ha within the Brazilian Moleques do Sul archipelago(Salvador & Fernandez, 2008). Some of the island populations we predict to speciate might therefore not survive long enough to speciate or might speciate but subsequently go extinct. ...
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Human activities are causing massive increases in extinction rates but might also lead to drastic increases in speciation rates; for example, after human‐mediated spread of species to otherwise unreachable landmasses. The long‐term net anthropogenic effects on biodiversity therefore remain uncertain. Our aim was to assess the combined anthropogenic effects of extinctions and speciations on biodiversity over geological time‐scales. Global. Present and predicted future. Terrestrial mammals. We estimated known anthropogenic and predicted future extinctions based on Red List categories from the International Union for Conservation of Nature. We inferred potential anthropogenic speciations, assuming that all introductions to isolated landmasses would, over time, evolve into distinct species. We then estimated changes in regional and global species richness and phylogenetic diversity attributable to these extinctions and speciations. We demonstrated that if all species introduced onto new landmasses develop into new species, the number of anthropogenic speciation and extinctions eventually become similar. However, even after accounting for an anthropogenic increase in speciation, our estimates suggest recovery times for phylogenetic diversity of several millions of years. Our results highlight that although humans are causing drastic biodiversity losses, human‐driven speciation could eventually counterbalance these losses in species numbers, whereas phylogenetic diversity, at least within our simulation scenarios, would remain permanently reduced. This conclusion, however, requires our pressures on biodiversity to cease soon and requires us to consider geological time‐scales rather than changes over this century.
... The Mediterranean insular endemic elephants are found in Pleistocene to early Holocene cave or open-air sites on more than a dozen islands of the Central (Sardinia, Sicily, Malta) and Eastern Mediterranean (N axos, P aros, Kýthnos, S erifos, D elos, Mílos, Astyp alaea, K asos, Crete, Tílos, Rhodes, Cyprus) (Kotsakis et al., 1980;Dermitzakis and de Vos, 1987;Kotsakis, 1990;Caloi et al., 1996;Doukas and Athanassiou, 2003;Theodorou et al., 2007a;Palombo et al., 2012;Sen et al., 2014;van der Geer et al., 2014). With the exception of the Sardinian Mammuthus lamarmorai (Forsyth Major, 1883) and the Cretan Mammuthus creticus (Bate, 1907), Mediterranean insular dwarf elephants most likely derive from founding populations of the large-sized Palaeoloxodon antiquus (Falconer and Cautley, 1847). ...
Article
Cyprus, the largest Eastern Mediterranean island, hosted a highly impoverished endemic mammalian fauna during the Pleistocene to early Holocene times. This was a result of its extreme biogeographic isolation since its formation, which prevented the immigration of most terrestrial mammals, except for those with apparent sea channel crossing abilities. The main faunal elements are the extremely dwarfed hippo Phanourios minor, commonly found in many sites across the island, and the dwarf elephant Palaeoloxodon cypriotes. The latter is a very small-sized elephant species, comparable in size with the Siculo-Maltese Palaeoloxodon falconeri. Larger dental specimens found sporadically during the last century, raised the possibility that a second endemic elephant, larger than P. cypriotes, may have also existed in Cyprus. Here we describe a skull recently excavated in the coastal area of Xylophágou, SE Cyprus, which provides evidence that, indeed, two elephant species have existed on the island. The larger species, Palaeoloxodon xylophagou n. sp., is still strongly dwarfed and characterised by elongated, low and wide skull, diverging tusk alveoli and comparatively large molars. Dimensionally the dentition is distinctly larger than P. cypriotes and close to Palaeoloxodon tiliensis, though the skull size is intermediate between P. tiliensis and P. falconeri. Both Cypriot elephant species exhibit morphological affinities with Palaeoloxodon antiquus, which is their probable ancestor. Stratigraphic data suggest that P. xylophagou is older (late Middle Pleistocene), while P. cypriotes is more recent (latest Pleistocene to early Holocene) and may have descended from the former or – less probably – evolved as a result of a separate, more recent colonisation event.
... This is due to the most robust morph of dwarf adults. Another dwarf elephant from Tilos, P. tiliensis, was substantially larger, the excavated femora of up to 700 mm (Theodorou et al. 2007) indicate that the Tilos elephant was around 185 cm at the shoulders and 1.3 tonnes in body mass. The medium-sized species, P. mnaidriensis, was over 200 cm at the shoulders and around 1.7 tonnes in body mass according to the material recovered from Puntali Cave (Ferretti 2007), although very large-sized specimens may be within the species, such as those found at the Contrada Fusco in association with middle-sized P. mnaidriensis remains. ...
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In recent decades there has been a growing interest in proboscideans’ body size, given that mass is highly correlated with biological functions. Different allometric equations have been proposed in the recent decades to estimate their body masses, based on a large number of living examples. However, the results obtained by these formulae are not accurate because extinct animals often had different body proportions and some were outside the size range of extant samples. Here the body mass of a large number of extinct proboscideans has been calculated by the Graphic Double Integration volumetric method which is based on technical restorations from graphical reconstructions of fossils employing photos, measurements and comparative anatomy of extant forms. The method has been tested on extant elephants with highly accurate results. The reconstructions necessary to apply this method give important information such as body proportions. On the other hand, equations to calculate the skeletal shoulder height have been developed, with a large number of published shoulder heights being recalculated. From the shoulder heights, several equations were created to find out the body mass of a series of extant and extinct species. A few of the largest proboscideans, namely Mammut borsoni and Palaeoloxodon namadicus, were found out to have reached and surpassed the body size of the largest indricotheres. Bearing this in mind, the largest land mammal that ever existed seems to be within the order of Proboscidea, contrary to previous understanding.
... Being excellent swimmers, elephants during the Pleistocene frequently colonized and became isolated on islands where they underwent significant changes in both skeletal structure and body mass. Among the different species that inhabited large and small Mediterranean islands, most originated from the mainland species Palaeoloxodon antiquus, and a couple from Mammuthus (see Palombo, 2001aPalombo, , 2007Theodorou et al., 2007;van der Geer et al., 2010van der Geer et al., , 2014Herridge, 2010;Herridge et al., 2014). The smallest taxa recorded in the Siculo-Maltese archipelago, undoubtedly are the epitome of the insular dwarfism and the most prominent examples of the so-called "Island rule" (Foster, 1964;Van Valen, 1973). ...
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During the period of 1958 and 1960, the richest sample of Palaeoloxodon ex gr. P. falconeri (104 individuals) was recovered from Spinagallo cave (Syracuse, Hyblean Plateau, SE Sicily). Subsequently, several composite skeletons were reconstructed. Four of them are today exhibited at the Paleontological Museum of Department of Earth Sciences of Sapienza University of Rome (MPUR). Three of the skeletons representing an adult male (MPUR/V n1), an adult female (MPUR/V n2) and a calf (MPUR/V n3), were analysed in order to reconstruct the physical appearance and estimate the body mass of the species. The rigorous skeletal restorations suggest that the living males approached a height of 100 cm at the shoulder and over 300 kg in body mass, whereas females were around 80 cm high and around 165 kg. The sexual dimorphism in Palaeoloxodon ex gr. P. falconeri was concluded to be comparable to extant elephants. The small size probably had a direct influence in the animals’ physiology and biology; including a shorter life span, rapid growth, and changes in thermoregulation mechanisms. The drastic allometric size reduction experienced by Siculo-Maltese dwarf elephants, produced noticeable changes in the skull, showing some paedomorphic features that were present in young P. antiquus and in extant juvenile elephants, and in the axial and appendicular skeleton proportions with respect to its putative mainland ancestor Palaeoloxodon antiquus. Some unique traits observed in the limb bones, suggest a more agile locomotion in P. ex gr. P. falconeri than other elephantids. Nevertheless, the most noteworthy change is the positive allometric increase of the brain case. The large change in brain proportions was related to the need to maintain the minimal functional volume of the brain when the size of the skull was drastically reduced.
... Paramount in these are the examples of dwarfed hippopotami, such as Hippopotamus minor, the smallest hippo that ever lived (Forsyth Major, 1902;Bate, 1906;Boekschoten and Sondaar, 1972). Other large mammals follow suit, with the world's smallest mammoth Mammuthus creticus appearing on Crete (early Pleistocene; Herridge and Lister, 2012), dwarf elephants on, e.g., Cyprus, Naxos and Tilos (Palaeoloxodon cypriotes, P. lomolinoi, P. tiliensis; late Pleistocene; Bate, 1903Bate, , 1904Bate, , 1905Theodorou et al., 2007;Sen et al., 2014;Van der Geer et al., 2014;Athanassiou et al., 2015;Mıtsopoulo et al., 2015) and a radiation of the endemic deer Candiacervus with eight species on Crete (De Vos, 1979). These islands were not connected to the mainland at any time during the geological period considered here (Marra, 2005), and were colonised by the focal taxa by sweepstake (chance) dispersal . ...
Article
The eastern Mediterranean has yielded some textbook examples of insular evolution among large mammals such as the world's smallest hippopotamus and mammoth. By contrast, gigantism among small mammals is limited, with the exception of the early Pleistocene murid Kritimys from Crete. The large body size of insular rodents can be related to an energetically advantageous position at the slow end of the mammalian fast–slow continuum. In order to test the hypothesis that the development of gigantism was hampered by the harsher climatic conditions of the middle and late Pleistocene, we constructed a dataset of endemic murids and cricetids from islands all over the world. Upto the middle Pleistocene, giant rodents can be found all over the world. However, in the later part of the Pleistocene and Holocene, these are only found at lower latitudes, suggesting that indeed the harsher conditions of the north no longer allowed insular rodents to develop the slow life-strategy that previously could still be achieved at these latitudes.
... Λεπτομερέστερη μεταγενέστερη βιομετρική ανάλυση ωστόσο, συμπέρανε ότι οι καταγραφείσες διαφορές στο μέγεθος οφείλονταν στον φυλετικό διμορφισμό ενός μόνο είδους (Theodorou 1983). Το 2007 το είδος αυτό προσδιορίστηκε με το όνομα Εlephas tiliensis (Theodorou et al. 2007). Στη παρούσα έρευνα το είδος αναφέρεται ως Palaeoloxodon tiliensis αναγνωρίζοντας την εγκυρότητα του γένους και ακολουθώντας την άποψη ότι το είδος Palaeoloxodon antiquus είναι η προγονική μορφή από την οποία προήλθαν οι ενδημικές νάνες μορφές των ελεφάντων (Shoshani andTassy 2005, Herridge 2010). ...
... Data of time of extinctions are based on published data for the following archipelagos: the West Indies (Cooke et al., 2011;MacPhee, 2009;MacPhee and Flemming, 1999; IUCN Red List), Eastern and Western Mediterranean (Athanassiou et al., 2015;Bover and Alcover, 2008;Burness et al., 2001;Delussu, 2000;Ferretti, 2008;Mangano, 2005;Marcolini et al., 2006;Theodorou et al., 2007;Turvey, 2009;van der Geer et al., 2010van der Geer et al., , 2014Willemsen, 2006;Wilson and Reeder, 2005;Sen et al., 2014), Lesser Sunda Islands (Aplin and Helgen, 2010;Bellwood, 1997;Louys et al., 2016;Turvey, 2009), Philippines (van der Geer et al., 2010, Canary Islands (Bocherens et al., 2006;Boye et al., 1992;Hutterer et al., 1988;Musser and Carleton, 2005), Table 1 Overview of mammalian biodiversity levels of discussed archipelagos or island groups. The asterisk is used to indicate extinct taxa. ...
Article
Extinction, speciation and immigration are the main factors shaping patterns of biodiversity on islands. In particular, the impact of the Late Pleistocene-Holocene extinction wave had a strong impact on the megafauna. Here we investigate the relationship between extinctions of insular endemic mammal species and their body mass, the size of the island and the first human arrival to the archipelago. Our data on islands worldwide show that megafauna was hit hard indeed. All islands lost their heaviest mammal species, whereas maximum surviving mammalian body size differs per archipelago, ranging from heavier than 100 kg (Philippines) to below 100 g (Canaries) and no surviving native mammals on the Galápagos. Although the number of extinctions is highest on larger islands, in line with predictions following from the species-area relationship, the percentage in relation to total number of endemic species is the lowest. Major part (almost 80%) of extinctions of insular endemics took place after the first human arrival, with the highest percentages during the Late Pleistocene (34.5%) and the Modern Era (31%). This indicates an increased rate of extinctions in the Modern Era, considering the substantially longer time span of the former period. Increased globalisation with introductions of alien species in combination with substantial anthropogenic habitat alteration likely underlies this pattern. Whether these extinction waves follow a fast or slow scenario (“blitzkrieg” versus “sitzkrieg”) remains unclear, but the gradual increase in extinctions through the Holocene, with a peak (31%) in the last 500 years, is suggestive of a slow scenario.
Article
Dwarf elephants are quite well known from the western Mediterranean islands, but they are still poorly documented in most eastern Mediterranean islands. This paper reports on the discovery of a third lower molar of a dwarf elephant from the island of Kassos, which is situated in the southern Aegean, between Crete and Karpathos. This molar is determined as Palaeoloxodon aff. creutzburgi, a dwarfed species known from the Late Pleistocene caves and deposits in Crete and derived from the mainland straight-tusked elephant P. antiquus. An upper molar (M3) from the island of Dilos, previously referred to Elephas antiquus or E. mnaidriensis, is also redescribed. It is almost identical to the upper molars of a paleoloxodontine elephant from Naxos. Its small size and lack of sufficient comparative material lead us to determine it as Palaeoloxodon sp. The palaeogeographic evolution of the Aegean region during the Pleistocene and its impact on the dispersal of elephants in the Aegean islands are discussed.
Article
It is undisputed that the use of computed tomography gives the researcher an inside view of the internal morphology of precious findings. The main goal, in this study, is to take advantage of the huge possibilities that derive from the use of CT Scans in the field of Vertebrate Palaeontology. Rare fossils skull parts (Ospetrosum of Elephas tiliensis from Tilos, Phanourios minor from Cyprus and Candiacervus sp. from Crete) brought to light by excavations, required further analysis of their inside structure by non destructive methods. Selected specimens were scanned and exported into Dicom files. These were then imported into MIMICS Software in order to develop the required 3D digital CAD models. By using distinctive reference points on the bone geometry based on palaeontological criteria, section views were created thus revealing the extremely complex inside structure and making it available for farther palaeontological analysis.
Article
This article describes for the first time in 50 years several proboscidean remains from the Pleistocene Philippines. The bones were excavated in the Cagayan Valley, in the northern part of the island Luzon. Since pygmy proboscideans are widely known from islands in the Mediterranean area, as well as in Indonesia and near the Californian coast, the main question that arose after studying this material is whether we are dealing with an endemic species. This article addresses questions about the taxonomy, biometry and dwarfism of endemic proboscideans. Biometrical comparisons with all available measurements from the Mediterranean area resulted in some interesting insights on pygmy proboscideans in general.
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As Alfred Russell Wallace once wrote, we live in a zoologically impoverished world, from which most of the largest, strangest and most spectacular animals disappeared quite recently. About two thirds of all animal species larger than 50 kg (the so-called megafauna) were extinct from the late Pleistocene onwards, starting in Australia at about fifty thousand years ago and following humans' footsteps is their expansion throughout Eurasia and the Americas. The extinctions went on through the Holocene, reaching islands all around the globe, that can be seen as 'time machines' where megafauna survived for millennia after the continental extinctions, such as the Caribbean, the islands off Alaska, and Wrangel Island in the Arctic Ocean. In Madagascar and New Zealand, extinctions are but a few centuries old. These late Quaternary extinctions were a global phenomenon that begs for a global explanation. Climatic hypotheses fail to explain these patterns for several reasons, for example, there were dozens of other glacial cycles throughout the Pleistocene, without associated mass extinctions; extinctions in Australia and the islands did not coincide with glacial peaks; and climate changes cannot explain why extinctions were systematically more recent on islands. However, the pieces of the puzzle immediately fit together when we observe the clear correspondence between the dates of humans' arrival and of megafaunal extinction in each landmass. Bernardo Araujo recently analysed the chronology of extinctions of megafaunal genera around the world. He found that extinctions took place closer than expected by chance to periods of high climatic variation alone in only two of the analysed cases, to dates of human arrival alone in seventy-four cases, and to both in eight cases, with 40 cases unexplained. Thus, anthropogenic impact is the most plausible and parsimonious main cause of the late Quaternary extinctions. In a modern view, the extinctions were a long process that took several millennia to occur in most continents, with a few stragglers like the Irish elk and the North American mastodons. Low reproductive potential was the main determinant of the extinct species; the apparent selection by size is an artefact of the inverse correlation between the two variables. The absence of evolved instincts against newly arrived humans, the difficulty of conserving meat and the lack of perception of the world's finitude must have contributed to the outcome. Thus, human-megafauna interactions are an important and undervalued part of human history that merits being represented on the UNESCO World Heritage List. Furthermore, learning from the extinctions of the past is crucial to allow us to minimise extinctions in the future. Candidate sites in the Americas might include those that show consumption of megafauna (such as Monte Verde), remarkable rock paintings (such as Serra da Capivara, Brazil) and the latest American megafauna (such as Las Breas de San Felipe, Cuba).
Book
Evolution on islands differs essentially from evolution on mainlands. Especially islands of the past are uniquely intriguing. Due to millions of years of isolation, exceptional and sometimes bizarre mammals evolved, such as pig-sized elephants and hippos, giant rats and gorilla-sized lemurs, formidable to their mainland ancestors. This timely and innovative book is the first of its kind to offer a much-needed synthesis of recent advances in the exciting field of the evolution and extinction of fossil insular placental mammals. It provides a comprehensive overview of current knowledge on fossil island mammals worldwide, ranging from the Oligocene to the onset of the Holocene. This book addresses evolutionary processes and key aspects of insular mammal biology, exemplified by a variety of fossil species. The authors discuss the human factor in past extinction events and loss of insular biodiversity. This accessible and richly illustrated textbook is written for graduate level students and professional researchers in evolutionary biology, palaeontology, biogeography, zoology, and ecology.
Article
There is possibly no other location in the world which has been so intensively influenced by human activity over a prolonged period as the Mediterranean. Virtually no ecosystems have been left untouched. Since prehistory, the human settlers of the Mediterranean islands brought about a radical turnover between ancient and modern mammalian faunas, introducing a variety of allochthonous continental taxa. The data available for the Mediterranean islands point to endemic mammalian extinction being largely the result of human activities of land clearance and the introduction of allochthonous animals. Today, this fauna is no longer characterised by the majority of the endemic mammals previously reported. It displays virtually the same species composition, being almost exclusively characterised by continental mammals whose appearance on the islands has essentially been influenced by man, and dominated by generalist species. The invasion of ecosystems by exotic taxa is currently viewed as one of the most important causes of the loss of biodiversity. Today, in view of the vulnerability of the insular ecosystems it is critically important to prevent further introductions. But this results in the question of how to treat the allochthonous mammalian populations of certified ancient anthropochorous origin, which instead deserve to be protected and considered in terms of a veritable "cultural heritage''. Moreover, their protection and their study can provide an opportunity for testing a range of different evolutionary theories.
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This chapter gives a concise overview of the faunas of Crete. Then, a comprehensive treatment is provided of the history of discoveries, biozones, or faunal units and the peculiarities and evolutionary aspects of individual endemic species or lineages. The fossil fauna of Crete, the largest island of Greece, is mainly known for its Pleistocene endemic taxa, amongst which are dwarf deer, dwarf elephants and mammoths, dwarf hippopotamuses, and giant mice. The typical fauna elements of this biozone – the Mus zone – are two chronospecies of mice, Mus bateae and Mus minotaurus – unrelated to the Cretan mice of the previous biozone – Creutzburg’s dwarf elephant, Cretan deer, the Cretan otter, and the Cretan shrew. Excavations in the many cave localities – of which Michael Dermitzakis, Elliot Lax, and George Iliopoulos and colleagues gave overviews – revealed a clear zonation in the Pleistocene fossil record.
Article
Islands are often regarded by scientists as living laboratories of evolution and an optimal context for the study of forces influencing evolution and diversification. Two main issues have been attentively scrutinized and debated: the loss of biodiversity and the peculiar changes undergone by island settlers, primarily changes in size of endemic vertebrates. Over time, several hypotheses have been formulated to explain the causal mechanism of body size modification. Faunas of those islands where mainland taxa migrate more than once provide the most interesting data to answer the question of whether or not trends of insular taxa result from a predictable response to differences in competition and availability of niches between insular and mainland environments. To contribute to the debate, the body size structure of the Pleistocene mammalian faunas from two Mediterranean islands, Sicily and Crete, were analyzed and compared with the structure of coeval mainland faunas. The results obtained suggest that: (i) size of endemic species does not directly depend on the area of islands; (ii) evolution and size of endemic species seems somewhat affected by the degree of isolation (constraining colonization from mainland) and physiography (sometimes permitting adaptive radiation); (iii) in unbalanced insular communities, the shift in size of non-carnivorous species largely depends on the nature of competing species; and (iv) body size of carnivorous species mainly depends on the size of the most available prey. Consequently, it is rational to suppose that the body size of insular mammals mainly results from the peculiar biological dynamics that characterizes unbalanced insular communities. Ecological interaction, particularly the intraguild competition, is the major driver behind the evolution of insular communities, leading towards an optimization of energy balance through a change in body size of endemic settlers.
Article
Full-text available
The structure of Proboscidean tusks, from the Quaternary Greek localities of Tilos (45 ka BP up to 4-3.5 ka BP), Aliveri (Pleistocene), and Vlachioti (Lower Pleistocene), are compared on the basis of the dentinal tubule density and the tubule maximum diameter. In addition observations are made on sections per- pendicular to the long axis of the tusk, with special concern to the preservability of the specimens. Although the taphonomic conditions play a very important role in this respect, a correlation also seems to exist between the above measurements and the degree of permeability and preservability of tusks. In addition, the values measured exhibit a reverse correlation with the tusk size. In fact the tusks of the dwarf elephants from Tilos, which are extremely brittle, have the largest density and tubule diameter.
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When the car ferry “Rethymnon” sails from Piraeus towards Crete one can already feel the strong endemic atmosphere of the island. Rethymnon itself is a beautiful historical town on Crete in an area containing many Pleistocene fossil mammal localities which have yielded endemic deer, elephants and murids. A striking thing on board the ferry are notices written in Japanese which suggest that the ship was probably not launched under the name Rethymnon and served in her earlier days on the Japanese islands. For a paleontologist this is a remarkable coincidence since the Pleistocene of Japan has also yielded unbalanced endemic faunas with a very uniform composition of elephant and deer like the fauna of Crete.
Taphonomical observations on the fossil bone material from the excavation of 1997, of the dwarf elephants from Charkadio cave on the Island of Tilos
  • G Lampropoulou
LAMPROPOULOU, G. (1999). Taphonomical observations on the fossil bone material from the excavation of 1997, of the dwarf elephants from Charkadio cave on the Island of Tilos (Dodecanese, Greece). Diploma paper. Surpervisor G. Theodorou Athens University. Department Of Historical Geology and Palaeontology (in Greek, Translated title), p. 100.
The fossil dwarf elephants of Charkadio Cave at Insel Tilos
  • G Theodorou
THEODOROU, G. (1983a). The fossil dwarf elephants of Charkadio Cave at Insel Tilos. Phd thesis, 232. (Offset publication in 500 copies).
Die fossilen Zwergelefanten der Höhle "Charkadio' auf der Insel Tilos (Dodekanes, Griechenland)
  • G Theodorou
THEODOROU, G. (1983b). Die fossilen Zwergelefanten der Höhle "Charkadio' auf der Insel Tilos (Dodekanes, Griechenland). Anz. Akad. Wiss., Mathem. -nat., Kl., 120, 83-85, Wien.
Quaternary Continental and Marine Deposits in the caves of the Aegean Islands, Crete and Coastal Peloponessus and their importance for understanding past environmental changes. Speleo brazil 2001. II Symposium on Archaeology and Paleontology in caves
  • G Theodorou
THEODOROU, G. (2001). Quaternary Continental and Marine Deposits in the caves of the Aegean Islands, Crete and Coastal Peloponessus and their importance for understanding past environmental changes. Speleo brazil 2001. II Symposium on Archaeology and Paleontology in caves. July 15/22, 2001, 258-260, Brasilia.