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The greater Japanese shrew-mole, Urotrichus talpoides, has a wide and thick tail like a baseball bat with bristles like bottle brushes. It is known that not only length variations but also the width variations are observed in the tails of U. talpoides. To understand such width variations of the tail, we examined morphological and histological characteristics. The width variation was not related to the season when captured or aging, as indicated by the skull sizes. In addition, tail vertebra width was not correlated with tail width. On the other hand, according to histological observation of tail skin, the ratio of subcutaneous tissue/corium indicating the thickness of the subcutaneous tissue layer was positively correlated with the tail width (p < 0.05). The thickness of the subcutaneous tissue layer means that the rich adipose tissue and cells observed were unilocular, then identified as white adipose cells. It is well known that one of the functions of white adipose cells is to store excess energy as neutral fat. Thus, it is suggested that U. talpoides stores an energy source as adipose cells in the skin of the tail, demonstrating that tail width variations are caused by the thickness of the subcutaneous tissue layer. [ABSTRACT FROM AUTHOR]

The discovery of small, very well-defined and perfectly preserved tooth marks on the humerus of a mole, Talpa cf. europaea (TE9, Sima del Elefante, Sierra de Atapuerca, Burgos), is extraordinary. To date, no micromammal fossil is known with puncture prints produced by a bite with a clear or delimited morphology that would permit its detailed study. The exceptional character of the finding may raise questions and suspicions about alteration and taphonomic agents. However, we have evidence that both the marks in the mole humerus are due to the action of biting and that this bite corresponds to the dentition of Beremendia fissidens. After all, not only large predators bite, as this article intends to demonstrate. [ABSTRACT FROM AUTHOR]

The damage on the surface of a mole fossil humerus from the early Pleistocene site of Sima del Elefante (Atapuerca, Burgos, Spain) has been recently interpreted as bite marks of the extinct shrew Beremendia fissidens. The present work considers this attribution not evident, and it stresses some doubts on the feasibility of a shrew leaving bite marks on a bone using its incisors, as well as the physical and ethological inconsistencies that it would imply. [ABSTRACT FROM AUTHOR]

One of the rarest fossil mammals of the Neogene of North America is the desman, which dispersed to North America from Eurasia. The desmans, notably the genus, Gaillardia, did not persist in North America but were able to widely disperse, with occurrences known from New Mexico, Oregon, and Nebraska. Only three North American localities had previously been known to produce water moles, but a new discovery from southern Oregon, Lake County, adds to the known distribution. A tephra associated with the fossil specimens produced an 40Ar/39Ar date of 5.74 ± 0.01 Ma. Therefore, the Fort Rock Formation, which produced the specimens, was deposited during the latest Hemphillian North American Land Mammal Age (NALMA). The Gaillardia specimens are associated with fish, anurans, shrews, beavers (Dipoides), rabbits, and arvicolin rodents (Cosomys) indicating a riparian environment of deposition. [ABSTRACT FROM AUTHOR]

The oldest talpid, Eotalpa, was previously known only from isolated cheek teeth from the European late Middle Eocene to earliest Oligocene. Screenwashing of Late Eocene sediments of the Hampshire Basin, UK, has yielded cranial and postcranial elements: maxilla, dentary, ulna, metacarpals, distal tibia, astragalus, calcaneum, metatarsals and phalanges. In addition to M1-2 myotodonty, typical talpid features are as follows: ulna with long medially curved olecranon and deep abductor fossa and astragalar body with lateral process. However, Eotalpa retains certain soricid-like primitive states ( M1 preparacrista, P4 with prominent mesiolingual protocone lobe, strongly angled astragalar neck and calcaneum with no space for a cuboid medial process) not found in modern talpids. Eotalpa is more derived than the most primitive living talpid Uropsilus in having lost the M1-2 talon shelf, developed a convex radial facet on the ulna, an incipient proximal olecranon crest, relatively shorter metapodials and depressed manual unguals. Its astragalus with medial trochlear ridge taller than the lateral one and massive medial plantar process is typical of the Lipotyphla. Eotalpa lacks synostosis of tibia and fibula, found in other Talpidae, Soricidae and Erinaceidae, suggesting that synostosis in these groups has been independently acquired. Cladistic analysis places Eotalpa as stem member of the Talpidae and shows that much homoplasy arose during the early evolution of the family. Ground dwelling in Eotalpa is indicated by the following: astragalus with a medially dipping head, curved in a single plane; calcaneum with distal peroneal process and strongly overlapping ectal and sustentacular facets; and matching sized ectal and sustentacular facets on calcaneum and astragalus. These features would have restricted ankle mobility. Ungual and metatarsal shape and ulnar structure suggest a primitive stage in fossorial evolution and argue against a semiaquatic precursor stage in talpid fossoriality. Shrew-moles may represent a reversal to surface foraging rather than an intermediate stage in fossoriality. [ABSTRACT FROM AUTHOR]

Habitat segregation has been reported for the Japanese shrew-moles by several studies. However, there is a lack of surveys aimed at characterizing the ecological separation occurring between U rotrichus talpoides and D ymecodon pilirostris. In this paper, possible reasons for this ecological separation are proposed for the first time. A geometric morphometrics analysis was performed on first lower molars and mandibles of both fossil and extant specimens. The results evidenced that U. talpoides evolved a hypsodont configuration and a more robust mandible bearing an enlarged second incisor, while D. pilirostris maintained the primitive brachyodont morphology and a slender mandible. The fossil specimens proved to be very similar to their extant relatives. The shape analyses of m1 and the mandible suggest that U . talpoides possesses a more efficient feeding behaviour compared with that of D . pilirostris. Moreover, the derived state of the mandible morphology, associated with a larger size, suggests that U . talpoides largely displaced D . pilirostris and confined it to isolated highland areas by means of competition for food resources. [ABSTRACT FROM AUTHOR]

The clade Talpidae consists of specialized fossorial forms, shrew-like moles and semi-aquatic desmans. As with all higher jawed vertebrates, different functional, phylogenetic and developmental constraints act on different parts of dentary influencing its shape. In order to determine whether morphological variation in the dentary was unified or dispersed into an integrated complex of structural–functional components, a morphometric analysis of the mole dentary was undertaken. The dentary was subdivided into component parts – horizonal ramus; coronoid, condylar, angular processes of the ascending ramus – and outline-based geometric morphometric methods used to quantify, compare and contrast modes of shape variation within the clade. These were successful in revealing subtle differences and aspects of shape important in distinguishing between mole genera. Closer examination of shape variation within the two fully fossorial mole clades (Talpini and Scalopini) revealed several similarities in ascending ramus shapes between genera from each clade. For example, the broad, truncated appearance of the coronoid process in the talpine genera Talpa and Parascalops was shared with the scalopine genus Scapanus. Also, the more slender, hook-shaped coronoid process of Euroscaptor and Parascaptor (Talpini) closely resembles that of Scalopus (Scalopini). Interestingly, subspecies (one from each clade) more closely resembled genera other than their own in coronoid process shape. Important distinctions in horizontal ramus shape were found to exist between the two clades, such as the extent of curvature of the ventral margin and relative depth of the horizontal ramus. Results show shape variation in this region is correlated with dental formulae and the relative sizes of the teeth. The taxonomically important dentition differences characteristic of mammals are also reflected in the horizontal ramus results. Moreover, these results suggest size may be affecting shape and the extent of variation in, for example, the coronoid and condylar processes between the semi-aquatic moles Desmana and Galemys. It is likely that the effects of morphological integration seen at this level of analysis – covariation between shapes of dentary components – may exist because interacting traits are evolving together. Horizontal ramus and coronoid process shape, for example, are similar across Scapanus and Parascalops, but both these shapes have diverged in Scalopus. © 2008 Trustees of the Natural History Museum (London). Journal compilation © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153, 187–211. [ABSTRACT FROM AUTHOR]

Casts of the foraging tunnels of eastern American moles ( Scalopus aquaticus ) show impressions from the moles' mani along the lateral walls. The number of discernable impressions ranges from one to five, each showing two or three long, flat, blunt-ended claws. The size and shape of the impressions matches the claws on the paddle-like manus of S. aquaticus . The impressions are spaced at regular intervals of about two cm, and probably represent points at which the mole pushed off from the tunnel wall with alternating laterad digging strokes. Tunnel width generally exceeds height by about 15%, reflecting the laterally compressed body of the mole. These tunnel casts help show that clear, recognizable traces can be preserved in loose, humic soils, and demonstrate the type of traces left by a “lateral-thrust” digger with fully sprawled stance, such as S. aquaticus . Identification of traces on the tunnels of living moles may be applied to the fossil record, in which fossilized burrows with similar marks could be attributed to extinct burrowing moles or mole-like locomotion. [ABSTRACT FROM AUTHOR]