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We re−describe the type material of the tiny African tragulid “Dorcatherium” moruorotensis from the early Miocene of Kenya, and erect the new genus Afrotragulus, the first African Miocene tragulid that does not belong to Dorcatherium. This new taxon is characterized by its elongated and stretched lower molars with a unique morphological dental pattern that strongly contrasts with that of Dorcatherium. We additionally include the former “Dorcatherium” parvum, also a small species from the early Miocene of Kenya, into the new genus Afrotragulus as Afrotragulus parvus, figuring it for the first time. We discuss the usefulness of body size as the main taxonomical criterion for studying the Tragulidae. And finally we comment on the taxonomical and morphological diversity of tragulids in the moment of their sudden early Miocene re−apparition and expansion in the Old World.
The Anchitheriinae are a group of browsing horses with a widespread distribution throughout the Miocene. The subfamily includes the genera Hypohippus, Megahippus, Kalobatippus, Anchitherium, and Sinohippus. In the present paper we compare the remains of a giant anchitherine from the Spanish site of Nombrevilla−1, “Anchitherium” sampelayoi, with other species of Anchitherium from Europe, the North American genera Megahippus and Hypohippus, and the Asian genus Sinohippus. These comparisons allow us to suggest the inclusion of this large Spanish browsing horse in the Asian genus Sinohippus, rather than in Anchitherium. This proposal is made on the basis of some morphological traits from the upper cheek teeth of the Nombrevilla−1 fossils, and their large size, which clearly is outside the range of all other known European Anchitherium.
We describe the most complete and best−preserved materials assigned to Simocyon from Spain. Specimens come from the late Miocene (Vallesian) locality of Batallones−1, Province of Madrid and are assigned to Simocyon batalleri. Cranial, mandibular and dental anatomy of S. batalleri from Batallones−1 is described and compared with those of known species of Simocyon. We review the systematic status and the definition of the species of Simocyon and we analyse the morphological variation within Simocyon. Three species are recognized as valid. S. batalleri is known from several Vallesian localities (mainly MN 10) of Spain. S. diaphorus, from the early Vallesian of Germany (Mammal Zone MN 9), is the geologically oldest European species. The type species S. primigenius is Turolian in age and known from several localities of Europe, North America, and China. The species includes the junior synonyms S. zdanskyi and S. marshi. The status of Simocyon hungaricus is not resolved. Simocyon simpsoni is excluded here from Simocyon and reassigned to its original generic name Protursus. On the basis of the material described here, we propose a differential diagnosis for Simocyon batalleri. This species is morphologically intermediate between the more primitive S. diaphorus, which has a less reduced p3; and the more derived S. primigenius, characterized by a modified mandible (e.g., more vertical and more expanded coronoid process, longer angular process). The evolution of the genus Simocyon is characterized by a trend toward a more crushing adaptation involving at least a modification of the posterior part of the mandible. A reconstruction of the skull and life appearance of Simocyon is proposed.
Nest building effort has received scant attention in the literature although it may involve costs which can be detected as physiological stress. We prolonged nest construction effort in a population of Spanish Pied Flycatchers by removing nests from nest-boxes and forcing females to build a second nest. In comparison with control nests, the experimental females had to work for longer periods and accumulate more nest material, but nest construction rates (g of nest material per day of construction) were not affected. There was a positive association of clutch mass with nest construction rate. To measure physiological stress, we captured females shortly after laying to obtain blood samples for heat-shock protein quantification. Heat-shock proteins quantify stress at cell level. The level of HSP60 in peripheral blood was positively associated with total nest construction rate (including second nests for experimental females), but not with laying date, clutch mass or experimental treatment. A third of the variation in the HSP60 level was explained by the nest construction rate. Fast nest builders are physiologically stressed, suggesting that the nest construction rate may constitute an index of female physiological performance.
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