Structure and composition of the incisor enamel of extant and fossil mammals with tooth pigmentation

The inclusion of iron compounds in teeth, which impart a red to orange colour to them, is a phenomenon shown by several groups of vertebrates in different periods of their evolution. Incisors from fossil and extant shrews and from extant rodents were sectioned and studied with the techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) to compare their structure and the distribution of Fe. The enamel in white- and red-toothed soricids has three layers; two of them are divided into two zones in the red-toothed species. However, the most external layer varies among taxa; it is well defined in Sorex but difficult to identify in the Early Pleistocene genera Beremendia or Dolinasorex. In the arvicoline rodent Terricola, only two layers can be defined, the outer of which is divided into two zones depending on the presence or absence of Fe. The Fe proportions in the larger soricids reach up to 45%, but in rodents only up to 10% (weight % with respect to Fe + Ca + P). The STEM study shows that in a fossil soricid the Fe phases form clusters of nanometric particles of very poor crystalline oxides or hydroxides surrounding the apatite crystals that form the enamel

Mitochondrial simple sequenze repeats and 12s – rRNA gene reveal two distinct lineages of Crocidura russula (Mammalia, Sorcidae)

A short segment (135 bp) of the control region and a partial sequence (394 bp) of the 12S-rRNA gene in the mitochondrial DNA of Crocidura russula were analyzed in order to test a previous hypothesis regarding the presence of a gene flow disruption in northern Africa. This breakpoint would have separated northeast-African C. russula populations from the European (plus the northwest-African) populations. The analysis was carried out on specimens from Tunisia (C. r. cf agilis), Sardinia (C. r. ichnusae), and Pantelleria (C. r. cossyrensis), and on C. r. russula from Spain and Belgium. Two C. russula lineages were identified; they both shared R2 tandem repeated motifs of the same length (12 bp), but not the same primary structure. These simple sequence repeats were present in 12–23 copies in the right domain of the control region. Within the northeast-African populations, a polymorphism of repeat variants, not yet found in Europe, was recorded. A neighbor-join tree, which was built by sequences of the conserved 12S-rRNA gene, separated the two sister groups; it permitted us to date a divergence time of 0.5Myr. Our data discriminated two different mitochondrial lineages in accordance with the previous morphological and karyological data. Ecoclimatic barriers formed during the Middle Pleistocene broke the range of ancestral species in the Eastern Algeria (Kabile Mountains), leading to two genetically separate and modern lineages. The northeast-African lineage can today be located in Tunisia, Pantelleria, and Sardinia. The northwest- African lineage (Morocco and West Algeria), reaching Spain by anthropogenic introduction, spread over north Europe in modern times. The Palaearctic C. russula species is monophyletic, but a taxonomical revision (ie, to provide a full species rank for the northeast taxa and to put in synonymy some insular taxa) is required

[The fossil record of the Eurasian Neogene insectivores (Erinaceomorpha, Soricomorpha, Mammalia) : Part I / L.W. van den Hoek Ostende, C.S. Doukas and J.W.F. Reumer (editors)]: Poland

Introduction Despite the 19th century tradition of mammalian palaeontology in the present territory of Poland, the oldest records of insectivores are found in the papers of Andreae (1904), Schlosser (in Zittel, 1911) and Wegner (1913), who described the fauna from the Middle Miocene (MN 6) locality of Opole 1 in Silesia. The insectivores were represented in this locality by Metacordylodon schlosseri (Andreae, 1904) (Dimylidae), Talpa minuta Blainville, 1838 (Talpidae), and Erinaceus sansaniensis Lartet, 1851 (Erinaceidae). According to Wegner (1913) the latter form was similar to the Miocene hedgehog found at Sansan in France. The later revision of the Sansan material showed that it was not uniform. Part of it was transferred to the genus Lantanotherium Filhol, 1888, and another part to Amphechinus Aymard, 1849 (Baudelot, 1972). As the material from Opole 1 (except the holotype of the Metacordylodon schlosseri) disappeared during the Second World War, it is difficult to assess the taxonomy of the hedgehog from Opole 1. Before the Second World War only one paper mentioned (most probably Pliocene) insectivores from Polish territory: Sorex sp., Talpa sp., and Erinaceus sp. from the Poludniowa Cave near Wojcieszów in Silesia (Zotz, 1939). In the 1950s and 1960s some Pliocene and Pleistocene small mammal faunas were studied by Kowalski (1956, 1958, 1960) and Sulimski (1959, 1962a, b). Both authors described several new species, mostly shrews. The studied localities were situated in the Cracow-Wieluń Upland, a belt of Upper Jurassic limestones, well known for accumulations of fossil-bearing deposits, especially in caves and karst fissures

Data from: Systematics and macroevolution of extant and fossil scalopine moles (Mammalia, Talpidae)

Scalopini is one of the two fully fossorial mole tribes in the family Talpidae, with remarkable adaptations to subterranean lifestyles. Most living Scalopini species are distributed in North America while a sole species occurs in China. On the other hand, scalopine fossils are found in both Eurasia and North America from upper Oligocene strata onwards, implying a complex biogeographical history. The systematic relationships of both extant and fossil Scalopini across North America and Eurasia are revised by conducting phylogenetic analyses using a comprehensive morphological character matrix together with 2D geometric–morphometric analyses of the humeral shape, with a specific emphasis on Mioscalops, a genus commonly found in North America and formerly known as Scalopoides. Our phylogenetic analyses support the monophyly of the tribe Scalopini as well as a proposed two‐subtribe‐division scenario of Scalopini (i.e. Scalopina and Parascalopina), although Proscapanus could not be assigned to either subgenus. Our geometric–morphometric analyses indicate that the European Mioscalops from southern Germany should be allocated to Leptoscaptor, which in turn implies that Mioscalops may be endemic to North America and never arrived in Europe. Examination of biogeographical patterns does not unambiguously determine the geographical origin of Scalopini. Nevertheless, it does support multiple transcontinental colonization events across Asia, Europe and North America. Scapanulus oweni, distributed in central China, is the only remaining representative of one of those out‐of‐North‐America migrations, whereas scalopine moles are common in North America nowadays with up to five species