Marsupial Mammals What is a Marsupial? Marsupials are a group of mammals that have an external pouch located on their mother's abdomen in which they carry their young. Most marsupials live in Australia, where they have evolved into some unique and unusual animals. Marsupials range in size from the 1.8 meter tall red kangaroo which weighs 90kgs to the tiny, shrew-like long-tailed planigale which is just 6 cm in length and weighs only 4 gms.
Whale ribs loosely articulate with their thoracic vertebrae at the proximal end, but they do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as opposed to resisting the force of water pressure.
Sure, I know, whales are whalesâ¦but did you know that all dolphins and porpoises are whales too? Itâs true; they are toothed whales just like the great sperm whale made famous by Moby Dick. As a matter of fact, the sperm whale is the only toothed whale that is considered a great whale because of its immense size.