How is a platypus different from a penguin?

Differences between the platypus and the beaver are:

• A beaver is a rodent which bears live young; a platypus is a monotreme (egg-laying mammal)
• A beaver has large front teeth; platypuses have a bill with no teeth, but grinding plates
• Platypuses live in Australia and beavers live in North America and Canada.
• A platypus digs a burrow in the side of a riverbank or creekbank, with an extra chamber at the end for incubating and raising its young; a beaver chews down trees to eat and makes a dam to raise its young.
• The platypus is the only venomous mammal - the male has a spur on its hind leg with which to inject poison that is extremely painful and has long-lasting effects
• The beaver's tail is broader and flatter than a platypus's, and covered with special scales. The platypus's tail is covered with dense fur.
• Their tails serve different purposes. The beaver's tail is used to help propel it along in the water. The platypus's tail is used as a rudder, for steering when it is swimming, but it also stores fat. A thicker tail is the sign of a healthier platypus.