Society for Reproductive Biology Founders’ Lecture 2006. Life in the pouch: womb with a view
Marilyn B. RenfreeDepartment of Zoology, The University of Melbourne, Vic. 3010, Australia. Email: m.renfree@unimelb.edu.au
Reproduction, Fertility and Development 18(7) 721-734 https://doi.org/10.1071/RD06072
Submitted: 28 June 2006 Accepted: 11 July 2006 Published: 18 August 2006
Abstract
Marsupials give birth to an undeveloped altricial young after a relatively short gestation period, but have a long and sophisticated lactation with the young usually developing in a pouch. Their viviparous mode of reproduction trades placentation for lactation, exchanging the umbilical cord for the teat. The special adaptations that marsupials have developed provide us with unique insights into the evolution of all mammalian reproduction. Marsupials hold many mammalian reproductive ‘records’, for example they have the shortest known gestation but the longest embryonic diapause, the smallest neonate but the longest sperm. They have contributed to our knowledge of many mammalian reproductive events including embryonic diapause and development, birth behaviour, sex determination, sexual differentiation, lactation and seasonal breeding. Because marsupials have been genetically isolated from eutherian mammals for over 125 million years, sequencing of the genome of two marsupial species has made comparative genomic biology an exciting and important new area of investigation. This review will show how the study of marsupials has widened our understanding of mammalian reproduction and development, highlighting some mechanisms that are so fundamental that they are shared by all today’s marsupial and eutherian mammals.
Acknowledgments
I owe a special debt to my close colleagues Geoff Shaw, Andrew Pask and my husband Roger Short as well as to my collaborators past and present: Hugh Tyndale-Biscoe, Jean Wilson, Richard Behringer, Anne McLaren, Jenny Graves and Fumi Ishino. Much of this work has been aided and abetted by my many capable post-doctoral fellows and graduate students who have joined me in the excitement of discovery of all things marsupial.
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