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Abstract: The detection of diagenetic alteration is critical for palaeoclimate reconstruction that is based on the oxygen isotope composition of fossil bones and teeth. So far, no direct chemical proxy has been found to track diagenetic modification of the oxygen isotope ratios. Here, a new approach to identify diagenetic changes of δ18OPO4 values in skeletal apatite of small mammals by means of triple oxygen isotope analysis (16O, 17O and18O) is presented. Our method is based on the fact that inhaled air oxygen (O2) has an isotope anomaly on its rare isotope 17O. Inhaled air O2 is a major source of oxygen in small land-living mammals. A fraction of the anomaly is transferred via body water to skeletal apatite, where it can be detected by means of δ17O and δ18O analyses. The approach, considering the current analytical uncertainty, is restricted to small mammals with body masses≤1kg. This is due to the low specific metabolic rates of large mammals, resulting in a lower fraction of oxygen inhaled via breathing relative to oxygen from other sources in their body water. Remnant negative 17O anomalies derived from in vivo inhaled O2 have been detected in enamel bioapatite of Eocene to Miocene rodent teeth while dentine of the same teeth lacks significant 17O anomalies. This suggests preservation of the original phosphate oxygen isotope composition in enamel of these small mammal teeth. In contrast, 17O anomalies in dentine have been erased due to diagenetic alteration with isotopically normal diagenetic fluids. Triple oxygen isotope analysis of bioapatite thus seems to be a useful new proxy to directly detect diagenetic alterations of the δ18OPO4 values of small mammal teeth. [Copyright &y& Elsevier]

Uric acid (UA) is the end product of purine metabolism in humans due to the loss of uricase activity by various mutations of its gene during the Miocene epoch, which led to humans having higher UA levels than other mammals. Furthermore, 90% of UA filtered by the kidneys is reabsorbed, instead of being excreted. These facts suggest that evolution and physiology have not treated UA as a harmful waste product, but as something beneficial that has to be kept. This has led various researchers to think about the possible evolutionary advantages of the loss of uricase and the subsequent increase in UA levels. It has been argued that due to the powerful antioxidant activity of UA, the evolutionary benefit could be the increased life expectancy of hominids. For other authors, the loss of uricase and the increase in UA could be a mechanism to maintain blood pressure in times of very low salt ingestion. The oldest hypothesis associates the increase in UA with higher intelligence in humans. Finally, UA has protective effects against several neurodegenerative diseases, suggesting it could have interesting actions on neuronal development and function. These hypotheses are discussed from an evolutionary perspective and their clinical significance. UA has some obvious harmful effects, and some, not so well-known, beneficial effects as an antioxidant and neuroprotector. [ABSTRACT FROM PUBLISHER]

Abstract: The late Neogene of the Mediterranean region is marked by significant faunal and floral turnover in terrestrial ecosystems, paleogeographic and paleoceanographic changes associated with the Messinian Salinity Crisis (MSC), and regional climate transition associated with the onset of northern hemisphere glaciation. In this paper we report stable oxygen isotope compositions (δ 18O) of terrestrial mammal faunas from the Late Miocene, Pliocene and Pleistocene of Spain, and compare these data with Late Miocene mammal δ 18O values from northern Libya. Since tooth enamel δ 18O from modern horses has been demonstrated to be a reasonable proxy for the δ 18O of local meteoric water, which is in turn strongly dependent on mean annual temperature (MAT), we use the δ 18O of fossil horse tooth enamel to estimate MAT. Our paleotemperature reconstructions are consistent with global cooling during the late Cenozoic, with MAT for the Late Miocene that is warmer than today by ∼1–2°C in NE Spain and by ∼4–5°C in SE Spain. The difference of ∼8–9°C between NE and SE Spain for the Late Miocene is ∼60% greater than the MAT difference between these same areas today. The δ 18O values from Libya are lower than those for southern Spain, and may suggest cooler and/or wetter climates in northeastern Africa during the latest Miocene and early Pliocene. We examined intrafaunal δ 18O patterns to make interpretations about paleoecology and to qualitatively assess paleoaridity. Comparisons of δ 18O values between clades are consistent with a semi-aquatic lifestyle for anthracotheres, hippopotamids, and castorids. We also compare intra-tooth samples of enamel and dentine to examine possible diagenetic alteration of these materials. Comparisons of enamel and dentine δ 18O suggest slight diagenetic alteration of dentine, but we demonstrate that these δ 18O values can be used to reconstruct reasonable values of diagenetic water δ 18O. Overall, our data do not support large climatic changes in the Iberian Peninsula during the MSC, but are consistent with long-term global cooling and sharper latitudinal climate gradients in Spain during the Neogene. [Copyright &y& Elsevier]

One of the classic examples of faunal turnover in the fossil record is the Miocene transition from faunas dominated by anchitheriine horses with low-crowned molar teeth to faunas with hipparionine horses characterized by high-crowned teeth. The spread of hipparionine horses is associated with increased seasonality and the expansion of open habitats. It is generally accepted that anchitheriine horses did not display an evolutionary increase in tooth crown height prior to their extinction. Nevertheless, to test whether anchitheriines showed any changes interpretable as adaptation to local conditions, we analyzed molar teeth from multiple populations of Anchitherium in three dimensions. Our results show differences in tooth morphology that suggest incipient hypsodonty in Spain, the first region experiencing increasingly arid conditions in the early Miocene of Europe. Furthermore, analyses of tooth wear show that Spanish specimens cluster with present ungulates that eat foliage together with grasses and shrubs, whereas German specimens cluster with present-day ungulates that eat mostly foliage. Taken together, even a taxon such as Anchitherium, with a long and successful history of forest adaptation, did respond to regional environmental changes in an adaptive manner. [ABSTRACT FROM AUTHOR]

In the proximity of Jumilla (Murcia, Spain) there is a site called Hoya de la Sima with mammal footprints dating from the Upper Miocene. This site is an old gypsum quarry where footprints of Hipparion, Pecoripeda, Carnivora, Ursidae, and Proboscidea were discovered. While the site was being cleaned and conditioned after the discovery to protect the prints, Camelidae and other prints were unearthed and are currently being studied. The description of the Camelidae ichnites demonstrates that these belong to a new ichnogenera, produced by the prints of Paracamelus. The grouping of trackways is congruent with the gregariousness of these animals and with the concentration observed in similar sites. [ABSTRACT FROM AUTHOR]

Abstract: The Mokrá-Western Quarry exhibits the rare occurrence of Early Miocene (MN 4) vertebrate fauna within the area of the eastern part of Central Europe. In addition to a rich fauna of reptiles and mammals, two fossiliferous karst joints (Mokrá-Western Quarry, 1/2001 Turtle Joint and Mokrá-Western Quarry, 2/2003 Reptile Joint) yielded a rich fauna of amphibians including 13 amphibian taxa: Salamandridae: Mioproteus sp., Chelotriton sp., type I, Chelotriton sp., type II, Triturus aff. roehrsi, Triturus cf. marmoratus, Triturus sp. (T. cristatus species group), Chioglossa meini, Mertensiella mera, Salamandridae gen. and sp. indet.; Pelobatidae: Pelobates sanchizi; Ranidae: Rana sp. (synklepton Rana esculenta); Bufonidae: Bufo sp. The first records of the West European species Triturus cf. marmoratus and Chioglossa meini are reported from the eastern part of Central Europe indicating the wide distribution of those taxa throughout the whole of Europe as early as MN 4. The oldest known record of Pelobates sanchizi documents the Early Miocene presence of representatives closely related to the extinct Late Oligocene representatives of Pelobates. The slow evolution of amphibian species is documented by the presence of Triturus cf. marmoratus and the oldest known occurrence of the extinct salamander Mertensiella mera. [Copyright &y& Elsevier]

Abstract: The mammal locality of Antonios is one of the few known early–middle Miocene ones of Greece with large mammals. It is situated in Chalkidiki Peninsula (Macedonia, Greece) and includes both small and large mammals. The study of the carnivores found in Antonios indicates the presence of the following taxa: Proputorius cf. P. sansaniensis, Protictitherium gaillardi, Protictitherium cf. P. crassum, Percrocuta sp., Percrocutidae indet. and Pseusaelurus romieviensis. The material of each taxon is described, compared with other material from various Eurasian localities and determined. The species P. cf. sansaniensis and P. romieviensis are traced for first time in Eastern Mediterranean, while Percrocuta for first time in Greece. The presence of the other carnivoran taxa in the Antonios fauna is also interesting as they are recognized in older stratigraphic levels enriching our knowledge about their stratigraphic distribution. The carnivores of Antonios cannot offer significant data for the dating of the fauna but its age is discussed using the data coming from the carnivores as well as those from older studies of the micromammals and suoids. [Copyright &y& Elsevier]

A rich variety of vertebrate footprints is known from a number of Upper Eocene to Lower Miocene localities of Navarre (western Pyrenees). The sediments were deposited in a wide range of depositional environments, from marginal marine to diversified terrestrial. Abundant bird tracks have been found in the coastal deposits of the Upper Eocene Liedena Sandstone of the Yesa and Itzagaondoa areas. Ciconiiformes-like (Leptoptilostipus pyrenaicus) and Charadriiformes-like (Charadriipeda ichnospp.) footprints have been recognized. Mammal ichnites have been discovered in the Oligocene and Lower Miocene deposits of Navarre. Equoid perissodactyl ichnites similar to those of Plagiolophustipus occur in the Oligocene fluviatile rocks of the Mués Sandstone of Olexoa and the Rocaforte Sandstone near Oibar and Sada. Trackways of entelodontids (Entelodontipus) are known in fluviatile-palustrine beds of the Oligocene Mués Sandstone of Olkotz. Additionally, bird (Charadriiformes-like) tracks are known in fluviatile-palustrine floodplain deposits of the Lower Miocene Ujué Formation of Los Arcos. In the same area, the Desoio and Los Arcos outcrops have also yielded perissodactyl trackways of possible Equoidea. Trackways of rhinocerotids (?) and artiodactyls (possibly Pecoripeda) are described from the Lower Miocene (Ramblian) palustrine limestones marginal to the Lerín Formation of Kaparroso and from alluvial fan deposits of the Uncastillo-Perdón Formation of Altzorritz, respectively. [ABSTRACT FROM AUTHOR]

The Laventan Quebrada Honda Fauna of southern Bolivia is one of the best sampled middle Miocene South American faunas. The present study describes the toxodontid, interatheriid and mesotheriid notoungulates from Quebrada Honda and summarizes the present state of knowledge of the fauna. Toxodontid specimens from Quebrada Honda include two isolated molars, one upper and one lower. The upper molar compares favourably with Paratrigodon and may represent a new species, but too little material is known to make an adequate diagnosis. The lower molar may pertain to the same taxon, or to a distinct species that is even more poorly represented. A new species of the interatheriid Miocochilius is described, M. federicoi, on the basis of a partial skull. It differs from M. anomopodus in its significantly smaller size (at least 20 per cent smaller based on linear upper molar dimensions); relatively wider P4 with deeper lingual sulcus; more prominent middle lobes on upper molars; and M3 with deeper lingual sulcus and more prominent metastyle (distal lobe). The generic allocation of this new species is considered tentative, pending a better understanding of the phylogenetic relationships among currently recognized species of Miocochilius and Protypotherium. Mesotheriids are represented at Quebrada Honda by a pair of poorly preserved mandibles that are referred to Plesiotypotherium minor, a species previously recorded from slightly older deposits near Cerdas, Bolivia. A newly revised faunal list for Quebrada Honda is compiled that includes 30 species of non-volant mammals, 27 of which have been identified to at least genus level. This revised faunal list is used to compare Quebrada Honda to other well-sampled middle–late Miocene faunas (including La Venta, Columbia; Collón-Curá, Argentina; and Arroyo Chasicó, Argentina) using the Simpson Index of faunal similarity. In order to compensate for inadequately identified specimens (i.e. those not identified to genus level), minimum and maximum values of faunal similarly were estimated using two different sets of assumptions. The analysis indicates that the middle-latitude Quebrada Honda Fauna is more similar to the slightly older high-latitude fauna of Collón-Curá than to the contemporaneous low-latitude fauna of La Venta, suggesting that isolating mechanisms between the low and middle latitudes were in place during the early and/or middle Miocene. The relative paucity of taxa shared between Quebrada Honda and La Venta, despite their contemporaneity, suggests that the system of South American Land Mammal ‘Ages’ (SALMAs) may not be useful for biocorrelation between low-latitude faunas and those from elsewhere in South America. [ABSTRACT FROM AUTHOR]

New Zealand (NZ) has long been upheld as the archetypical example of a land where the biota evolved without nonvolant terrestrial mammals. Their absence before human arrival is mysterious, because NZ was still attached to East Antarctica in the Early Cretaceous when a variety of terrestrial mammals occupied the adjacent Australian portion of Gondwana. Here we report discovery of a nonvolant mammal from Miocene (19-16 Ma) sediments of the Manuherikia Group near St Bathans (SB) in Central Otago. South Island, NZ. A partial relatively plesiomorphic femur and two autapomorphically specialized partial mandibles represent at least one mouse-sized mammal of unknown relationships. The material implies the existence of one or more ghost lineages, at least one of which (based on the relatively plesiomorphic partial femur) spanned the Middle Miocene to at least the Early Cretaceous, probably before the time of divergence of marsupials and placentals >125 Ma. Its presence in NZ in the Middle Miocene and apparent absence from Australia and other adjacent landmasses at this time appear to reflect a Gondwanan vicariant event and imply persistence of emergent land during the Oligocene marine transgression of NZ. Nonvolant terrestrial mammals disappeared from NZ some time since the Middle Miocene, possibly because of late Neogene climatic cooling. [ABSTRACT FROM AUTHOR]

Abstract: The Aït Kandoula basin is one of the richest Miocene micromammals bearing areas known in the South of the High-Atlas, whereas the large mammal remains are scarce. The Afoud section in the center of the basin is well calibrated with the Geomagnetic Polarities Time Scale (KC95), and shows a succession of six fossiliferous layers. Beside rodents, the Afoud AF6 layer yields among some large mammal remains, a proboscidean identified as a Gomphotheriidae indet. from the enamel microstructure of a molar chip. This determination is grounded on the thickness of the enamel, on the prisms type, on the thinness and characteristics of the 3D zone and outside on the preferential course of the prisms. [Copyright &y& Elsevier]

Recent discovery of an abundant and diverse late Miocene fauna at Toros-Ménalla (Chad, central Africa) by the Mission Paléoan- thropologique Franco-Tchadienne provides a unique opportunity to examine African faunal and hominid evolution relative to the early phases of the Saharan arid belt. This study presents evidence from an African Miocene anthracotheriid Libycosaurus, particularly well documented at Toros-Ménalla. Its remains reveal a large semiaquatic mammal that evolved an autapomorphic upper fifth premolar (extremely rare in Cenozoic mammals). The extra tooth appeared ≈12 million years ago, probably in a small northern African population isolated by climate-driven fragmentation and alteration of the environments inhabited by these anthracotheriids [Flower, B. P. & Kennett, J. P. (1994) Palaeogeogr. Palaeoclimatol. Paleoecol. 108, 537-555 and Zachos, J., Pagani, M., Sloan, L., Thomas, E. & Billups, K. (2001) Science 292, 686-693]. The semiaquatic niche of Libycosaurus, combined with the distribution and relationships of its late Miocene species, indicates that by the end of the Miocene, wet environments connected the Lake Chad Basin to the Libyan Sirt Basin, across what is now the Sahara desert. [ABSTRACT FROM AUTHOR]

A new genus of hypsodont equid, Scaphohippus, is recognized from the Green Hills Division (Ba1), Second Division (Ba1), and Barstow Faunas (Ba2) of the medial Miocene Barstow Formation, as well as from Ba1 and Ba2 faunas in the Punchbowl Formation of California, the Tesuque Formation of New Mexico, the Pawnee Creek Formation of Colorado, and the Olcott Formation of Nebraska. The genus includes two species, Scaphohippus sumani n. sp. and Scaphohippus intermontanus n. sp. Scaphohippus is a member of the “protohippine” clade, but is differentiated from its more derived sister taxon, Protohippus, by an arc-shaped incisor battery, a shorter I3-P1 diastema, and a more rounded protocone. The upper cheek teeth of S. sumani n. sp. have an unworn crown height of 40 mm. The protocone remains isolated until as much as 60% of wear, and the enamel fossettes are more complex than those of S. intermontanus n. sp. S. intermontanus n. sp. has an unworn crown height of 48–50 mm, the protocone opens by 30% of wear, and the enamel fossettes are simpler than those of S. sumani n. sp. Phyletic analysis shows S. sumani n. sp. to be the more primitive species. Similar facial and dental characteristics reveal a likely common ancestor with Merychippus insignis. The wider geographic and temporal range of S. sumani n. sp. reported here allows for useful phyletic and biogeographic interpretations. S. sumani n. sp. and M. insignis diverged during the late Hemingfordian (He2) of the Great Plains and both taxa dispersed throughout the western United States. S. intermontanus n. sp. is only recognized from the Barstow Formation, where it was likely directly descended from S. sumani n. sp. [ABSTRACT FROM AUTHOR]

There is disagreement among ecologists as to whether ecosystem system behavior in general is the net result of all of the complex internal system interactions (bottom-driven) or if the behavior is driven by a limited number of key processes (top-driven). If ecosystems are primarily bottom-driven in nature, then it is unlikely that any two complex ecosystems will ever behaviorally converge as a simple matter of probability, or that their behaviors will ever be predictable. Conversely, evidence of ecosystem convergence would suggest that the systems are top-driven, with the corollary that their behaviors can be understood (and therefore in principle predicted) without a complete understanding of their internal workings. Research has demonstrated that body mass distributions of terrestrial animals broadly reflect ecosystem function. Thus, comparable but causally disconnected terrestrial ecosystems that demonstrate similar body mass distributions would suggest ecosystem convergence. To look for this possible convergence, I generated body mass distributions in a time series for late Miocene North American mammal faunas from the Gulf Coastal Plains, Great Plains, and Pacific coastal region, and compared them with data from the modern Serengeti savanna region. The data show that during the early late Miocene Gulf Coastal Plain faunas resembled each other but were distinctly different from that of the Serengeti, the Great Plains fauna resembled the Serengeti, while the Pacific Coast fauna showed no resemblance to any of the others. However, during the latest Miocene the Gulf Coastal Plain faunas were transformed so as to strongly resemble the Serengeti fauna. The resemblance with the Serengeti was maintained by the Great Plains faunas until at least the end of the Miocene, while the Pacific Coast faunas remained distinctly different from the others. These findings suggest that the late Miocene ecosystems of the Gulf Coastal Plain and Great Plains regions (but not the Pacific Coast region) converged with that of the Serengeti savanna fauna and thus that these ecosystems were/are top-driven rather than bottom-driven in nature. [ABSTRACT FROM AUTHOR]

A new skull belonging to the speciesEurhinodelphis cocheteuxi(Cetacea, Odontoceti, Eurhinodelphinidae), found in the upper Lower–Middle Miocene of Antwerp (Belgium, southern margin of the North Sea Basin) associated with its ear bones (periotic, tympanic bullae, malleus and incus), is the basis of a redescription and systematic revision of the species. This species is then used as an isolated taxon in a phylogenetic study of extinct and extant odontocetes. The main results of the cladistic analyses are: a sister-group relationship betweenE. cocheteuxiand the extant family Ziphiidae (beaked whales), and a more basal position of the superfamily Physeteroidea (sperm whales) in the tree. The possible paraphyly of the family Eurhinodelphinidae needs further investigation. The results are compared with the most recent morphological and molecular analyses. The speciesE. bossi, described in the Miocene of Maryland (east coast of the USA, Calvert Formation) is recognized in the Miocene of Belgium for the first time. [ABSTRACT FROM AUTHOR]

Abstract: Machairodus kabir n. sp., described here, comes from the Late Miocene hominid locality of TM 266, Toros-Menalla, Chad. This species is more derived than the previously described Machairodus in having a more developed mental apophysis and more reduced premolars relatively to m1. Machairodus kabir n. sp. is the largest mammalian predator from the Toros-Menalla fossiliferous area, with an estimated body mass reaching 350–490 kg, which certainly allowed this felid to prey on large herbivores present at Toros-Menalla. To cite this article: S. Peigné et al., C. R. Palevol 4 (2005) . [Copyright &y& Elsevier]

During the 1998–2003 field seasons of the Uganda Palaeontology Expedition, dental remains of three catarrhine species were recovered from Moroto II, Uganda. Micromammals from the locality indicate a late Early Miocene to basal Middle Miocene (ca 17.5–17 Ma) age, younger than Rusinga (17.8 Ma), but similar in age to Buluk (17.2 Ma) and Kalodirr (17.2 Ma). This paper describes and interprets new catarrhines from the site, one of which is a victoriapithecid monkey, the second a new genus and species of small-bodied ape, and the third a large hominoid. A fourth species collected in the 1960''s is attibuted to Afropithecus turkanensis. To cite this article: M. Pickford et al., C. R. Palevol 2 (2003). [Copyright &y& Elsevier]

Carnivores are ecologically diverse mammals. Dietary adaptations vary from strict herbivory to pure carnivory. These adaptations have evolved independently several times within families, so evolution within the order is iterative. I used 2 databases to examine whether ecological adaptations have an effect on longevity or spatial distributions of fossil carnivores. Miocene hypercarnivorous species had, on average, the widest spatial distributions. Their temporal distributions were not significantly longer than those of other carnivores. Body size also had a significant interaction with maximum spatial distribution. Largebodied carnivores, regardless of feeding adaptations, had larger geographical ranges, but did not have greater longevity. However, when all the data were pooled, temporal distribution had a significant correlation with spatial distribution. The position of hypercarnivores at the top of the food chain and their specialized adaptations for meat eating probably increased their extinction risk to the same level of more narrowly distributed, less specialized carnivores. [ABSTRACT FROM AUTHOR]

New paleomagnetic data from southern Mexico provide a magnetostratigraphic framework to correlate mammal-bearing continental sections of the Suchilquitongo Formation to the Early Miocene part of the geomagnetic polarity time scale. A total of 127 paleomagnetic samples were collected from 40 horizons belonging to two sections. The sequence is characterized by a succession of cream to light pink to gray, thin- to medium-bedded tuffaceous sandstones and siltstones, partly silicified limestones, and a dominantly light green ignimbrite deposited in a fluviolacustrine environment. Remanent magnetization generally has been characterized by two components, a present-day field component with low-unblocking temperatures up to 350°C and a characteristic component with unblocking temperatures up to 580°–610°C. The characteristic component is interpreted as primarily based on antipodal populations of remanence data. Six sites at the top of the section (inclination = 40.5°, declination = 11.3°, α[sub 95] = 1.4, and Κ = 471) have a mean paleomagnetic direction rotated clockwise about 17° with respect to the expected Miocene direction derived from the North American polar wander curve (inclination = 354°, declination = 30°). According to bio-chronologic age, the magnetostratigraphic results from the mammal-bearing sedimentary-type section in the Suchil-quitongo area can be correlated with chron C5Dn-C5Cn3n at approximately 17.61­16.55 Ma. An age of about 17 Ma is proposed for the fossiliferous level, corresponding to an Early Miocene age. [ABSTRACT FROM AUTHOR]

The thick (>4000 m) coarsening-upward terrestrial Neogene sequence of the Sulaiman Range (Middle Indus Basin, central Pakistan) is the western extension of the Siwalik outcrop belt of the Sub-Himalayas. The near-shore to terrestrial sedimentation in the Sulaiman Range, represented by the Chitarwata Formation, began by the late Oligocene to basal Miocene when the main Himalayan foreland was primarily a non-depositional region. The fluvial system of channel–floodplain deposits was fully established in the late early Miocene, marking the beginning of the Vihowa Formation. There is a sudden increase in the proportion of sandstones to mudstones, and change in the geometry of the sandbodies, at the conformable contact of the Vihowa with the overlying Litra Formation. The trend of coarsening and increased complexity of sandbodies with more conglomerate interbeds continued upward from the Litra to the Chaudhwan Formation, which in the upper reaches becomes a conglomerate-dominant sequence. Our mammalian faunal collections from the Vihowa and Litra formations, though small, are definitive, providing a temporal framework for interpreting the Sulaiman depositional regimes in the context of Himalayan orogeny. The Vihowa and Litra mammalian faunas are strikingly similar to the Middle to Late Miocene Siwalik faunas from the Potwar Plateau. Fauna from the lower Vihowa records diversification in the small boselaphine bovid Eotragus around 17 Ma. The three-toed hipparionine horses appear in the lower Litra Formation, giving a Late Miocene age to those strata. The middle Litra Formation has entirely different species of bovids, suids, and giraffids suggesting a more open country habitat. Similar community restructuring with substantial faunal turnover occurred about 7.5–7.0 Ma on the Potwar Plateau. The Chaudhwan Formation is probably of Pliocene age. Paleocurrent data suggest a southerly flowing river system, which perhaps was part of a much larger river system, analogous to the modern Indus River, draining southwestern Himalayas since Miocene. The Chitarwata through Chaudhwan sequence in the Sulaiman Range contains an almost continuous terrestrial record of the Neogene, perhaps more complete than anywhere else in the Himalayan foreland. [Copyright &y& Elsevier]

The hipparions from the late Miocene locality Nikiti-2 (NIK), Macedonia, Greece are described and compared with those from the other Greek and Eurasian localities. Two species have been determined, the medium-sized Hipparion dietrichi and the small-sized Hipparion macedonicum, while a third large-sized Hipparion is also recognized. The scanty material of the latter species indicates similarities with Hipparion proboscideum, as well as with Hipparion mediterraneum and it is referred to as Hipparion sp. The locality is dated to early Turolian as this is proved by the resemblance of the hipparions from “Nikiti 2” faunal assemblage with those from the neighbouring localities of “Ravin des Zouaves 5” and “Prochoma 1”, of Axios Valley, Greece. Interesting differences, which are inferred by the comparison of the studied material with those of Axios Valley, Samos and Turkey, are also discussed. [Copyright &y& Elsevier]

Paleosols in the late Miocene Rattlesnake Formation reveal three successive paleoclimatic regimens that can be dated using cumulative paleosol development prior to the radiometrically dated Rattlesnake Ash-Flow Tuff (7.05 Ma). The basal Rattlesnake Formation (ca. 7.5–7.3 Ma) has a suite of weakly calcareous paleosols indicating subhumid paleoclimate (800–1000 mm mean annual precipitation or MAP) and seasonal waterlogging. A shift at ca. 7.3 Ma to semi-arid paleoclimate (MAP 500–850) is indicated by paleosols with calcic horizons at depths of 105–85 cm. A second shift at ca. 7.2 Ma ushered in an assemblage of soils with shallow (36–53 cm) calcic horizons, indicating semi-arid conditions (MAP 200–600 mm) not much different from today. Along with the climatic shifts documented by the paleosols there also are substantial changes in alluvial architecture and paleotopography. The lower Rattlesnake Formation (ca. 7.5–7.2 Ma) was deposited by a stream flowing northeast in an ancestral John Day Valley. The upper part of the formation (ca. 7.2–7.1 Ma) was deposited within large alluvial fans shed from the growing anticline of Picture Gorge Basalt to the north. Stepwise changes in former vegetation can also be interpreted from paleosols. The basal Rattlesnake Formation (7.5–7.3 Ma) has a suite of paleosols with root traces, clay skins and manganese nodules like those of riparian woodland and seasonally waterlogged riparian meadow. The succeeding paleoclimatic sequence (7.3–7.2 Ma) includes the earliest known mollic paleosols with deep (>50 cm) calcareous nodules, interpreted as former soils of tall grassland. Also found are manganese-stained paleosols of seasonally waterlogged meadows, and weakly developed paleosols of early successional riparian vegetation. A later paleoclimatic sequence (7.2–7.1 Ma) includes desert shrubland paleosols, as well as paleosols of early successional riparian vegetation. Fossil bones and teeth found in many paleosols indicate coeval changes in mammalian faunas. The major shift from woodland to grassland at ca. 7.3 Ma introduced into this area tall grassland ecosystems, including large cursorial horses and pronghorns. Aridification continued with the shift to shrubland ca. 7.2 Ma (early Hemphillian), which corresponds to continent-wide mass extinction of most remaining browsing mammals from the Clarendonian Chronofauna. [Copyright &y& Elsevier]

Abstract: Mazza and Rustioni [Mazza, P.P.A., Rustioni, M., 2008. Processes of island colonization by Oligo-Miocene land mammals in the central Mediterranean: New data from Scontrone (Abruzzo, Central Italy) and Gargano (Apulia, Southern Italy). Palaeogeogr. Palaeoclim. Palaeoecol. 267 (3–4), 208–215.] suggest that land bridges played an important role in the colonization of the Abruzzo–Apulian bioprovince, as shown by the fossil vertebrates from Scontrone and Gargano. Would they have been able to demonstrate that land bridges indeed played a role in the dispersion of mammals, this would have implied that we had to rethink the modes of colonization for many other isles and rewrite our theories on island biogeography. Unfortunately, their evidence falls short, and even though their paper provides new insights in the history of the insular faunas of the Apulia platform, there is no reason to assume that land bridges played any role in the colonization of these islands. [Copyright &y& Elsevier]

The living Laotian rodent Laonastes aenigmamus, first described in early 2005, has been interpreted as the sole member of the new family Laonastidae on the basis of its distinctive morphology and apparent phylogenetic isolation from other living rodents. Here we show that Laonastes is actually a surviving member of the otherwise extinct rodent family Diatomyidae, known from early Oligocene to late Miocene sites in Pakistan, India, Thailand, China, and Japan. Laonastes is a particularly striking example of the "Lazarus effect" in Recent mammals, whereby a taxon that was formerly thought to be extinct is rediscovered in the extant biota, in this case after a temporal gap of roughly 11 million years. [ABSTRACT FROM AUTHOR]