Are marsupials inferior?
• Lines of reasoning that they are: • Less diversity of habitat types • Less diversity of locomotion • Less diversity of foraging • No really big marsupials • Social organization is less complex • Not as speciose • Most diverse and numerous in Australia, where there is negligible competition with eutherians • Is the competitive disadvantage the result of their mode of reproduction? • Maybe. Their mode of reproduction limits the environments in which they can live. • Maybe not. Other factors include: • Cerebral cortex of marsupials is smaller and develops more slowly • Learning and behavioral flexibility is less developed in marsupials. • Behavior is less diverse. • They have a small number of chromosomes, which may make them less evolutionarily flexible. • Their reproductive rate is lower. • An alternate view is that marsupials are not necessarily at a competitive disadvantage in all circumstances.
