This bone is used to support the pouch. The marsupial brain case is small compared to placental mammals. The brain itself is missing some structures that placental mammals have. Yet without these structures, marsupials have demonstrated learning and problem-solving abilities that exceed those of several species of placental mammals. Besides kangaroos and opossums, marsupials include a surprising number of animals that resemble placental mammals.
Tasmanian wolves are dog-like marsupial carnivores.
Bandicoots are rabbit-like marsupial rats. Koalas are amazingly similar to bears. There are even marsupial squirrels, moles, weasels and cats. These close resemblances are examples of what scientists call parallel evolution. Post your thoughts in The Public Forum.