ornithorhynchid

The Ornithorhynchidae, commonly known as the platypus, is a family of monotremes, the only living representatives of which are the platypus and the echidnas. The family is characterized by its unique combination of features, including a duck-like bill, webbed feet, and a venomous spur on the hind foot. The platypus is native to eastern Australia, while the echidnas are found in Australia, New Guinea, and various Southeast Asian islands.

The platypus is a semi-aquatic mammal, spending much of its time in water. It has a streamlined body, a flat tail, and a bill that is used to probe the mud for food. The echidnas, on the other hand, are terrestrial mammals that spend most of their time on the ground. They have a long, sticky tongue that is used to lap up ants and termites.

The Ornithorhynchidae are unique among mammals in that they lay eggs instead of giving birth to live young. This is a characteristic shared with the echidnas, which also lay eggs. The platypus lays a single egg, while the echidnas lay multiple eggs in a leathery pouch.

The family is of particular interest to scientists due to its unique evolutionary history. The platypus and the echidnas are the only living representatives of a group of mammals that diverged from other mammals around 200 million years ago. This makes them an important subject of study for understanding the evolution of mammals.