Although their name would suggest otherwise, marsupials differ most from other mammals, not by the possession of a pouch, but in the anatomy of the reproductive tract. Marsupials also differ in other less well known but perhaps more fundamental ways from eutherians and monotremes. One of these appears to be the way the genes regulate sex determination and differentiation of the reproductive tract. Sexual differentiation in the North American marsupial, the Virginia opossum, Didelphis virginiana , and the Australian brush-tail possum, Trichosurus vulpecula was extensively studied more than 40 years ago. The respective roles of genes and hormones in the differentiation of marsupial gonads, genital ducts and external sexual structures, particularly the pouch and scrotum, remained an enigma.
|Author||M. B. Renfree|
|Secondary title||Journal of Zoology|