Phylogenetic analysis of 18S rRNA and the mitochondrial genomes of the wombat, Vombatus ursinus, and the spiny anteater, Tachyglossus aculeatus: Increased support for the Marsupionta hypothesis

Research output: Contribution to journalReview article

Abstract

The monotremes, the duck-billed platypus and the echidnas, are characterized by a number of unique morphological characteristics, which have led to the common belief that they represent the living survivors of an ancestral stock of mammals. Analysis of new data from the complete mitochondrial (mt) genomes of a second monotreme, the spiny anteater. and another marsupial, the wombat. yielded clear support for the Marsupionta hypothesis. According to this hypothesis marsupials are more closely related to monotremes than to eutherians, consistent with a basal split between eutherians and marsupials/monotremes among extant mammals. This finding was also supported by analysis of new sequences from a nuclear gene-18S rRNA. The mt genome of the wombat shares some unique features with previously described marsupial mtDNAs (tRNA rearrangement, a missing tRNA(Lys), and evidence for RNA editing of the tRNA(Asp)). Molecular estimates of genetic divergence suggest that the divergence between the platypus and the spiny anteater took place approximate to 34 million years before present (MYBP), and that between South American and Australian marsupials approximate to 72 MYBP.

Details

Authors
  • Axel Janke
  • Ola Magnell
  • G Wieczorek
  • M Westerman
  • Ulfur Arnason
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biological Sciences

Keywords

  • spiny anteater, Theria, phylogenetics, Marsupionta, wombat, mitochondrial DNA, 18S rDNA
Original languageEnglish
Pages (from-to)71-80
JournalJournal of Molecular Evolution
Volume54
Issue number1
Publication statusPublished - 2002
Publication categoryResearch
Peer-reviewedYes