Bifurcated (paired) reproductive tract Lateral vaginae Medial vaginal canal (Feldhamer et al 2007) Image: palaeo.gly.bris.ac.uk
Kangaroo Choriovitelline placenta Eutherian chorioallantoic placenta Less villi – less surface area- less gas exchange- less gestation time (Feldhamer et al 2007) Kangaroo Eutherian Image: (Feldhamer et al 2007).
Temporary reduced egg shell Lasts 2/3 of gestation Prevents mother’s immune system from rejecting egg (Dawson 1995)
Kangaroos have short gestation and longer lactation when compared to Eutherians Kangaroos develop more in pouch (Dawson 1995) Image: www.kangaroocenter.com Image: upload.wikimedia.org
Can produce 2 different types of milk synchronously Separately controlled mammary gland and teat for young in pouch than for young at foot (Krockenberger 1996; Joss et al 2009; Nicholas 1988)
Different composition of milk in each teat Four phases of milk production (Krockenberger 1996; Joss et al 2009; Nicholas 1988) Image: 1.bp.blogspot.com
Forelimbs must develop quickly to be usable for climb to pouch Hindlimbs have more time to develop Forelimbs show much less diversity Hindlimbs show much more diversity (Cooper and Steppan 2010).
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