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We have recently shown that rainfall, one of the main climatic determinants of terrestrial net primary productivity (NPP), can be robustly estimated from mean molar tooth crown height (hypsodonty) of mammalian herbivores. Here, we show that another functional trait of herbivore molar surfaces, longitudinal loph count, can be similarly used to extract reasonable estimates of rainfall but also of temperature, the other main climatic determinant of terrestrial NPP. Together, molar height and the number of longitudinal lophs explain 73 per cent of the global variation in terrestrial NPP today and resolve the main terrestrial biomes in bivariate space. We explain the functional interpretation of the relationships between dental function and climate variables in terms of long- and short-term demands. We also show how the spatially and temporally dense fossil record of terrestrial mammals can be used to investigate the relationship between biodiversity and productivity under changing climates in geological time. The placement of the fossil chronofaunas in biome space suggests that they most probably represent multiple palaeobiomes, at least some of which do not correspond directly to any biomes of today's world. [ABSTRACT FROM AUTHOR]

We discuss a proboscidean bone fragment discovered in southern Finland, including the morphological analysis of the bone, as well as pollen and diatom analyses from sediment contained in the marrow cavity. Preliminary analysis of the bone suggested petrification and thus an apparently old age, while the microfossil assemblages include numerous unequivocally pre-Quaternary pollen, spore, and diatom types. A Miocene age for the bone is determined based on the presence of the diatom genus Alveolophora , indicating a minimum age of 5 Ma, and based on the earliest appearance of proboscideans outside Africa, setting a maximum age of 19 Ma. Based on morphology, the bone is determined as a partial humerus of the left foreleg of a large proboscidean. The bone is tentatively assigned to cf. Deinotherium sp., which is consistent with the diatom-based minimum age. The pollen assemblage is rich in spores of shoreline pteridophytes, while the diatom assemblage is also consistent with a shoreline freshwater environment, suggesting that the bone was deposited post-mortem near the shore of a lake or a stream. Miocene sediments do not currently exist in southern Finland or in the near vicinity. This implies that the bone has been transported over a considerable distance. Due to the discovery of the bone in early-Holocene Baltic Sea clay, the final transport phase and deposition must have taken place via iceberg rafting. This was likely preceded by one or more phases of glacial and/or glacio-fluvial transport. While we are unable to conclusive ascertain the region of origin, the alkaline composition of the contained sediment and diatoms point towards the Russian Plain region in the east. This specimen represents the oldest mammalian bone discovered in Finland and the northernmost discovery of a Miocene proboscidean bone in Europe. [ABSTRACT FROM AUTHOR]

Abstract: The fossil record for the Late Miocene indicates that high latitudes were warmer than today and that the equator-to-pole temperature gradient was weak. Experiments with climate models have not been sufficiently able to represent warm polar conditions for the Late Miocene. This demonstrates that our explanation of warm high latitudes in the Late Miocene is not complete. In addition, heat transport mechanisms have not been so frequently addressed to understand the differences between the Late Miocene and modern climate. Here we present a model simulation for the Tortonian (11 to 7Ma) using a complex fully-coupled atmosphere–ocean general circulation model to address heat transport mechanisms relative to modern conditions. Because of an open Central American Isthmus, the zonal mean northward ocean heat transport in the Northern Hemisphere generally decreases in our Tortonian run. As a consequence, the northward atmospheric heat transport is stronger in the Tortonian experiment. In northern mid-latitudes, the sensible and latent heat fluxes related to transient eddies increase compared to today. The stronger poleward transient eddy heat transport in the Tortonian model run correlates with intensified stormtracks in the mid-latitudes. In the palaeoclimate model run, the increased northward transient eddy heat transport together with the different-than-present land surface cover leads to a warming of polar regions and, hence, to a reduction of the meridional temperature gradient. The low elevation of Tibet in our palaeoclimate experiment causes a general weakening of the monsoon system in Asia. The E-Asian monsoon precipitation decreases compared to our reference run, but monsoon rainfall in India increases. When comparing the model results with quantitative terrestrial proxy data, we observe some discrepancies for some specific localities. However, the large patterns in our Tortonian run agree fairly well with the fossil record. [Copyright &y& Elsevier]

Nearly five decades ago Berggren and Van Couvering proposed an Old World " Hipparion Datum" wherein a North American Hipparion extended its range across Eurasia and Africa as an "instantaneous prochoresis" populating the Old World. Four decades ago Woodburne and Bernor examined European and North African hipparion assemblages and proposed a number of distinct hipparion lineages, sharply departing from the mono-generic paradigm of previous work. Through the 1980s until now, hipparion systematic studies have delineated multiple superspecific groups of hipparions. Herein, we define 10 recognizable genus-rank Eurasian and African taxa delineating their chronologic occurrences, geographic extent and where data exists, their body mass and paleodietary preferences. Our study supports the current interpretation that a species of North American Cormohipparion extended its range into the Old World in the early late Miocene. Regional first occurrences of Cormohipparion are recognized in the Potwar Plateau, Pakistan and Sinap Tepe, Turkey 10.8 Ma. The slightly derived lineage Hippotherium is recorded earlier in the Pannonian C of the Vienna Basin, 11.4–11.0 Ma marking the chronologic "Hipparion" Datum at the lower boundary of Mammal Neogene (MN) Unit 9. Within MN 9, 11.2–9.9 Ma, Cormohipparion underwent a minor diversification whereas Hippotherium diversified in Central and Western Europe and China and Sivalhippus (S. nagriensis) originated in the Indian Subcontinent. Whereas Cormohipparion did not survive into the late Vallesian, MN10 (9.9–8.9 Ma), Hippotherium and Sivalhippus did and the Cremohipparion and Hipparion s.s. lineages originated. During the early and middle Turolian (MN11–12, 8.9–6.8 Ma) Hippotherium, Sivalhippus, Cremohipparion and Hipparion persisted and new lineages, Eurygnathohippus, Plesiohipparion, Baryhipparion and Shanxihippus originated. An initial extinction interval occurred at the end of the Miocene, MN13 (6.8–5.3 Ma) wherein all but one endemic species of Hippotherium, H. malpassi (Italy), Hipparion and several species of Cremohipparion became extinct. Lineage and species reduction continued across the Mio-Pliocene boundary so that by the beginning of the Pliocene (MN14, 5.3 Ma) only African species of Eurygnathohippus, Chinese Plesiohipparion houfenense and Proboscidipparion sinense remained. The later Pliocene (MN15–16, ca. 5.0–2.5 Ma) documents the persistence of endemic Chinese Baryhipparion insperatum , modest diversification of African Eurygnatohippus spp. and Chinese Plesiohipparion and Proboscidipparion spp. Eurygnathohippus made a limited geographic extension into the Indian subcontinent during MN16, whereas Pleisohipparion and Proboscidipparion extended their ranges into Eurasia during MN15 and MN16. The latest occurring hipparions are Proboscidipparion sinense at 1.0 Ma in China and Eurygnathohippus cornelianus in Africa <1.0 Ma. Old World hipparion lineages early on increased their body mass in MN9. During the Turolian interval (MN11–13) hipparion lineages diversified their body mass from very small (<100 kg) to heavy forms (>300 kg), with the smaller forms being predominately grass feeders and larger ones being mixed feeders. Decreased hipparion lineage and species diversity in the Pliocene was accompanied by increased average body size and hypsodonty probably in response to more seasonal Eurasian and African environments. There is no evidence that hipparions ever adapted to cold and dry Old World Pleistocene environments. • Overview of Old World hipparion evolution and ecology after the Hipparion Datum • Integrated paleobiogeography, dietary and body size trends of Old World hipparions • Molar crownheight of hipparion occurrences mapped on regional paleoclimate over time [ABSTRACT FROM AUTHOR]