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Australian Journal of Zoology Australian Journal of Zoology Society
Evolutionary, molecular and comparative zoology

The enigma of the platypus genome

Wesley C. Warren A C and Frank Grützner B
+ Author Affiliations
- Author Affiliations

A The Genome Center, Washington University School of Medicine, 4444 Forest Park Boulevard, St Louis, MO 63108, USA.

B School of Molecular & Biomedical Science, The University of Adelaide, Adelaide, SA 5005, Australia.

C Corresponding author. Email:

Australian Journal of Zoology 57(4) 157-165
Submitted: 21 April 2009  Accepted: 7 August 2009   Published: 26 October 2009


Over two centuries after the first platypus specimen stirred the scientific community in Europe, the whole-genome sequence of the duck-billed platypus has been completed and is publicly available. After publication of eutherian and marsupial genomes, this is the first genome of a monotreme filling an important evolutionary gap between the divergence of birds more that 300 million years ago and marsupials more than 140 million years ago. Monotremes represent the most basal surviving branch of mammals and the platypus genome sequence allows unprecedented insights into the evolution of mammals and the fascinating biology of the egg-laying mammals. Here, we discuss some of the key findings of the analysis of the platypus genome and point to new findings and future research directions, which illustrate the broad impact of the platypus genome project for understanding monotreme biology and mammalian genome evolution.


We thank Dr Marilyn Renfree and Dr Russell Jones for helpful comments and Dr Geoff Shaw for the use of the animal silhouettes used in Fig. 1.


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