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Most tapirs are good seed dispersers. An exception is the Malayan tapir, Tapirus indicus, a seed predator (mainly of large seeds). Little is known about the capacity for tapirs to disperse seeds throughout their evolutionary history. We used the occlusal surface area (OSA) of tapir cheek teeth as a predictor of seed dispersal potential in living and extinct tapir species. We used T. indicus as a reference for an extant tapir that mostly eats seeds. The OSA was calculated by multiplying the maximal width and length of molars and premolars. A threshold based on T. indicus OSA was projected onto a box plot analysis and used as a predictor for tapir seed dispersal potential. Ordination and statistical results suggest that tooth morphology is uniform between Tapirus species and that size is the main factor affecting variation. Maxillary teeth show greater variation in morphology than mandibular teeth between species. The results suggest that extant South American tapirs are good seed dispersers. North American tapirs present variable OSAs, and Asian tapirs have a low capacity for dispersion. All European tapirs were probably efficient seed dispersers. We present the first morphometric evidence for seed dispersal capacity in tapirs, with ramifications for tapir palaeoecology.

Two biogeographical units are generally recognized in the present shelf area of Argentina: the Magellanian and Argentinian Provinces. The two provinces differ in their fossil record. The evolution of these provinces has been characterized by migrations, extinctions, pseudoextinctions and, perhaps, even speciation events. Marine vertebrate assemblages with some similarities to the Argentinian fauna were already present in the Miocene, whereas no associations similar to those of the Magellanian fauna have been found in South America before the Pleistocene. Two successive major marine transgressions flooded northern Patagonia during the Miocene: the ‘Patagoniense’ (Early Miocene) and the ‘Entrerriense’ (Middle to Late Miocene). We analyse three rich fossil assemblages that were formed during these transgressions. The absence of Magellanian Miocene vertebrate assemblages is consistent with the hypothesis of a more southern distribution of the cold-temperate fauna at that time. In Patagonia, as in other regions, an increased number of living groups appeared from the Lower to Upper Miocene. The Late Miocene aquatic mammals had a modern aspect, and some of the fish species are still living in the South Atlantic Ocean. In this contribution, we stress that warm-temperate fishes and a high diversity of penguins are found together at the base of the Gaiman Formation. We hypothesize that penguins were adapted to live in warmer waters than those of the latest Cenozoic and the Recent. Finally, we recall that many taxa became extirpated because of the global temperature drops of the late Cenozoic. However, some fishes and pinnipeds which were extirpated only in the Atlantic Ocean are discussed here. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103, 423–440.