Marsupials are a unique group of mammals known for their distinctive reproductive system. Unlike most mammals, female marsupials give birth to tiny, underdeveloped young that continue to grow in a pouch on their mother's belly. This pouch provides a safe environment for the young to nurse and develop until they are ready to explore the world. Common examples of marsupials include kangaroos, koalas, and opossums. These animals are primarily found in Australia and nearby islands, although some species, like the opossum, can be found in the Americas. Marsupials have adapted to various habitats, from forests to grasslands, and play important roles in their ecosystems. Their unique characteristics make them fascinating subjects of study in the animal kingdom.