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.
Whale is the common name for a widely distributed and diverse group of fully aquatic marine mammals. They are an informal grouping within the infraorder Cetacea, excluding dolphins and porpoises, so to zoologists the grouping is paraphyletic.dontocetes feed largely on fish and squid. A few, like the sperm whale, feed on large invertebrates, such as giant squid. Grey whales are specialized for feeding on bottom-dwelling molluscs. Male whales typically mate with multiple females every year, but females only mate every two to three years.