[1] Abundant and well-preserved marine macrofossils on Seymour Island, Antarctica, provide a valuable resource to establish paleoenvironmental conditions at high southern latitudes during the warm Paleogene. Stable isotope, minor element, and Sr/Sr compositions have been measured for the aragonite bivalve Cucullaea from the Eocene La Meseta Formation. The Sr/Sr stratigraphy suggests an early to...

A biometric analysis of the lower teeth of Recent cow sharks (Hexanchidae) investigates the ontogenetic and phylogen− etic aspects of the dental characters employed by many ichthyologists and palaeontologists. The dental characters cur− rently used to separate two extant species of sixgill sharks (Hexanchus griseus and H. nakamurai) are analysed and the fossil record of their relatives reviewed...

middle-late eocene deep marine deposits (483 m.) of the islam-ghaleh section, south mashhad, rich in ichnofossils in shale and sandstone layers. these flysch type sediments are composed of sandstone, shale and marl in gray to green in color and are divided into five subunits. the lower boundary of these successions is gradual with red conglomerate and sandstone and their upper boundary is gradu...

Five new ostracod species belonging to the subfamily Trachyleberidinae have been described. They are Paragrenocythere monilis and Peloriops levisulcata from the Maastrichtian of Iraq; Oertliella petraensis from the early Palaeocene (middle – late Danian) of Jordan; Reticulina syriaensis from the Palaeocene of Syria and Reticulina ninurta from the middle – late Eocene of Iraq.

The Middle to Late Eocene sediments of Texas have yielded a wealth of fossil material that offers a rare window on a diverse and highly endemic mammalian fauna from that time in the southern part of North America. These faunal data are particularly significant because the narrative of mammalian evolution in the Paleogene of North America has traditionally been dominated by taxa that are known f...

Tarka and Tarkadectes are Middle Eocene mammals known only from the Rocky Mountains region of North America. Previous work has suggested that they are members of the Plagiomenidae, an extinct family often included in the order Dermoptera. Here we describe a new primate, Tarkops mckennai gen. et sp. nov., from the early Middle Eocene Irdinmanha Formation of Inner Mongolia, China. The new taxon i...

An engraving made by a scolytid bark beetle, assigned to the genus Dendroctonus of the tribe Tomicini, has been identified on a mummified, middle Eocene (45 Ma) specimen of Larix altoborealis wood from the Canadian High Arctic. Larix altoborealis is the earliest known species of Larix, a distinctive lineage of pinaceous conifers that is taxonomically identifiable by the middle Eocene and achiev...

1 The global carbon cycle The global carbon cycle encompasses the sum of processes that determine the amount of carbon within, and fluxes between, different carbon reservoirs on Earth (Fig. 1). These processes are quantitatively important on a range of timescales and can induce both short-term fluctuations and changes in steady-state conditions1–3. On timescales of up to centuries and thousands...