Comparative post-weaning cranial ontogeny in two bandicoots (Mammalia, Peramelomorphia, Peramelidae): Isoodon macrourus (Peramelinae) and Echymipera kalubu (Echymiperinae).

FLORES, D.A.; ABDALA, F.; GIANNINI, N.P.

ZOOLOGY

ELSEVIER GMBH

Año: 2013 vol. 116 p. 372 - 384

0944-2006

The ontogeny of the skull has been studied in several marsupial groups such as didelphids, microbio-theriids, and dasyurids. Here, we describe and compare the post-weaning ontogeny of the skull in twospecies of bandicoots, Echymipera kalubu (Echymiperinae) and Isoodon macrourus (Peramelinae), analyz-ing specific allometric trends in both groups, describing common (and specific) patterns, and discussingthem on functional and phylogenetic grounds. Growth patterns were analyzed both qualitatively andquantitatively, including bivariate and multivariate analyses of allometry. We also evaluated charac-ter transformation and phylogenetic signals of the allometric patterns in several groups of marsupialsand some placentals. We identified morphological changes between juvenile and adult stages in bothspecies of peramelids, many related to the development of the trophic apparatus. Notable differenceswere detected in the patterns of growth, suggesting divergences in ontogenetic trajectories between bothspecies. Both bivariate and multivariate methods indicate that positive allometries in E. kalubu apply tolongitudinal dimensions, whereas in I. macrourus, positive allometries are restricted to vertical dimen-sions of the skull. The comparison of the allometric trends of two bandicoots with previously studied taxareveals that although peramelids exhibit a particularly short gestation period and divergent morphologycompared to other marsupials, their pattern does not show any particular trend. Some allometric trendsseem to be highly conserved among the species studied, showing weak phylogenetic signal. Marsupialsin general do not show particular patterns of post-weaning skull growth compared with placentals.