Ontogenetic morphology and allometry of the cranium in the common European mole (Talpa europaea)

The common European mole (Talpa europaea) has been the focus of many studies because of its fossorial lifestyle and related sensory and postcranial specializations. However, because of extensive fusion and pneumatization of the adult skull, many aspects of the cranial morphology of T. europaea are poorly understood. Here we present the 1st detailed study of cranial development in T. europaea, using an ontogenetic series of cleared and stained prenatal specimens to examine bone homologies, sequence of ossification, and prenatal allometry. The enigmatic lacrimal, jugal, and mastoid bones are all identified in prenatal specimens. The jugal and lacrimal bones fuse with the maxilla during prenatal growth, explaining previous difficulties with their identification in adults. T. europaea is anomalous among placental mammals in delaying the ossification of the alisphenoid and the orbitosphenoid until after birth. Analyses of allometry for 16 measures of individual bones show marked differences when postnatal specimens are included or excluded. Coefficients of allometry based on prenatal specimens are nearly twice those of analyses including subadult specimens. Comparisons with other taxa are limited by the lack of similar prenatal data, but the pattern exhibited by T. europaea differs significantly from those observed in studies of postnatal allometry in other mammals. These results may reflect differences among taxa or between prenatal and postnatal stages

Ossification sequence in the mole Talpa occidentalis (Eulipotyphla, Talpidae) and comparison with other mammals

The skeleton of mammals has been the subject of detailed anatomical and functional studies for centuries, and investigations of its ontogeny enjoy a long tradition (Starck 1995). However, knowledge of the timing of ossification is restricted to few species. Most available data of this kind pertain to species used in the lab or domesticated animals (e.g., Curgy 1965). Here we report on the ossification timing in the Iberian mole Talpa occidentalis (Fig. 1), based on the study of a developmental series obtained in studies of reproductive biology and growth in this species (e.g., Barrionuevo et al., 2004 F.J. Barrionuevo, F. Zurita, M. Burgos and R. Jiménez, Developmental stages and growth rate of the mole Talpa occidentalis (Insectivora, Mammalia), J. Mammal. 85 (2004), pp. 120–125. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (5)Barrionuevo et al. 2004). This study complements those on the ossification patterns in the European mole Talpa europaea (Prochel 2006; Goswami and Prochel 2007) and in other eulipotyphlans (Prochel et al. 2004)

Skeletogenesis and sequence heterochrony in rodent evolution, with particular emphasis on the African striped mouse, Rhabdomys pumilio (Mammalia)

Data documenting skeletal development in rodents, the most species-rich ‘order’ of mammals, are at present restricted to a few model species, a shortcoming that hinders exploration of the morphological and ecological diversification of the group. In this study we provide the most comprehensive sampling of rodent ossification sequences to date, with the aim of exploring whether heterochrony is ubiquitous in rodent evolution at the onset of skeletal formation. The onset of ossification in 17 cranial elements and 24 postcranial elements was examined for eight muroid and caviomorph rodent species. New data are provided for two non-model species. For one of these, the African striped mouse, Rhabdomys pumilio, sampling was extended by studying 53 autopodial elements and examining intraspecific variation. The Parsimov method of studying sequence heterochrony was used to explore the role that changes in developmental timing play in early skeletal formation. Few heterochronies were found to diagnose the muroid and caviomorph clades, suggesting conserved patterning in skeletal development. Mechanisms leading to the generation of the wide range of morphological diversity encapsulated within Rodentia may be restricted to later periods in development than those studied in this work. Documentation of skeletogenesis in Rhabdomys indicates that intraspecifc variation in ossification sequence pattern is present, though not extensive. Our study suggests that sequence heterochrony is neither pivotal nor prevalent during early skeletal formation in rodents

Morphology of the axial skeleton of seven bat genera (Chiroptera: Phyllostomidae)

ABSTRACT Here we present detailed descriptions and comparisons of the axial skeleton of seven species of bats belonging to five subfamilies of Phyllostomidae of different trophic guilds. The material examined consisted of 34 complete skeletons of seven species. For five of the studied species, previous descriptions have not been conducted, and for the vampires only limited information is available, so that descriptions for these species are here completed. The axial skeleton has characters that allow grouping of the species phylogenetically of the same subfamily and by feeding habits. At the same time, there are characters that associate species from different subfamilies with different types of diet or ways to obtain food