order: diprotodontiadiprotodontia suborder: phalangeriformesphalangeriformes family: pseudocheiridae...

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Character Marsupial state Placental stateDiversity 6% of living mammal species 94% of living mammal species

size not as large larger range of body sizes

structural adaptations less diverse flying (wings), marine (fins)

Reproduction[Figs. 10.7]

brief gestation; semiembryonic young; body mass 1% of mother. Need for precocious grasping forelimbs may constrain adaptability

long gestation period; young more developed at birth; body mass up to 50% of mother

Placenta [Fig. 9.11] choriovitelline (usually)  chorioallantoicLactation period [Fig. 10.7]

long short

Investment of energy in motherhood

lower, altricial younghigher, reproduce more rapidly (usually), precocial young

Cerebral Cortex/ Braincasesmooth and complex, slow development, smaller volume (maybe)

fast development, greater volume (maybe)

Behavioural plasticity uncommon great range of behavioursTerritoriality uncommon common and important

Antipredator behaviour not well developedhighly developed, particularly in herding animals; capable of sustained high speeds

Epipubic bones present absentBaculum [Fig. 9.3] absent presentAuditory bullae derived from alisphenoid bone varies, but not alisphenoid

primitive dental formula 5/4-1/1-3/3-4/4 3/3-1/1-4/4-3/3

Recall- chorioallantoic placenta in Order Peramelemorphia

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