Molecular evidence for the pattern and timing of cladogenesis in dasyurid marsupials

Citation
C. Krajewski et al., Molecular evidence for the pattern and timing of cladogenesis in dasyurid marsupials, ZOOL J LINN, 130(3), 2000, pp. 375-404
Citations number
98
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences
Journal title
ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY
ISSN journal
0024-4082 → ACNP
Volume
130
Issue
3
Year of publication
2000
Pages
375 - 404
Database
ISI
SICI code
0024-4082(200011)130:3<375:MEFTPA>2.0.ZU;2-P
Abstract
Recent molecular studies have provided estimates of phylogeny for nearly al l living and recently extinct species in the Order Dasyuromorphia, the domi nant clade of insectivorous-carnivorous marsupials in Australasia. We revie w these studies along with morphology-based ones, and present an analysis o f all cytochrome b, 12S rRNA, and protamine P1 gene sequences available. In light of these results, we provide a revised suprageneric classification a nd assess the implications of molecular and paleontological data for dasyur id cladogenesis. Molecular results divide extant dasyurids (Dasyuridae) int o four major clades apart from the numbat (Myrmecobiidae) and thylacines (T hylacinidae). We recognize these clades as tribes Dasyurini (Dasyurus, Phas colosorex, and allied genera) and Phascogalini (Antechinus, Murexia, Phasco gale) in the Subfamily Dasyurinae, and tribes Sminthopsini (Sminthopsis, Ni ngaui: Antechinomys) and Planigalini (Planigale) in the Subfamily Sminthops inae. Each tribe shows a basal radiation of lineages corresponding to gener a or species groups. Our results concur with the most recent previous synth esis of dasyurid phylogeny in many respects, but subsumption of New Guinean 'phascolosoricines' and 'muricines' within Dasyurini and Phascogalini, res pectively, constitute significant differences. In particular, the sister-pa iring of 'phascolosoricines' with a Dasyurus-Sarcophilus clade implied by m olecular data is difficult to reconcile with anatomy. Divergence rates of m itochondrial sequences are calibrated approximately by comparing thylacine- to-dasyurid distances with the age of the oldest thylacinid (Badjcinus, lat est Oligocene). Estimated cladogenic dates suggest that extant subfamilies shared a common ancestor around 24 Mva and that major radiations began late in the mid-Miocene, consistent with the results of previous paleontologica l studies. The late-middle and late Miocene corresponds to an episode of fa unal turnover in Australian marsupials (including the decline of thylacinid and bandicoot genera, as well as the rise of dasyurids) and to a time when uplift of the New Guinean highlands accelerated the transition from rainfo rest to drier habitats. Our findings are consistent with the hypothesis tha t continent-wide climate changes modulated macroevolution across these inde pendent marsupial clades. (C) 1999 The Linnean Society of London.