Comparative postnatal ontogeny of the skull in an australidelphian metatherian, Dasyurus albopunctatus (Marsupialia: Dasyuromorpha: Dasyuridae)

FLORES, D. A., N. GIANNINI, Y F. ABDALA

JOURNAL OF MORPHOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Año: 2006 p. 426 - 440

0362-2525

We describe the cranial ontogeny of an australidelphian marsupial, Dasyurus albopunctatus, using a combination of qualitative and quantitative approaches.We examined in detail qualitative morphological changes of just weaned in dividuals as compared tool to adults; specifically, changes in 31 morphological structures (e.g., processes, foramina) and 38 changes in cranial joints.We also interpreted growth invariant structures in terms of their functional relevance.We performed a multivariate allometry analysis based on 14 cranial measurements taken from 31 specimens encompassing the entire postweaning period. Three variables (height of occipital plate, breadth of braincase, and height of mandible)showed the same allometric trends in D. albopunctatus and the three marsupial species studied previously in the same framework (Didelphis albiventris, Lutreolina crassicaudata, andDromiciops gliroides).In addition, D. albopunctatus shared allometric trends in two variables(length of the upper postcanine row and length of the orbit) with the microbiotheriid D. gliroides. Most of the growth trends observed are interpreted as linked to the predominantly carnivorous dietary habit of adult D. albopunctatus. Because dasyuromorphians are most likely basal to the major Australasian radiation of marsupials, knowledge of ontogenetic changes in D. albopunctatus may shed light on the evolution of ontogeny in the highly diverse Australasian marsupial fauna.