All Egg-Laying Mammal Orders

Egg-Laying Mammal Orders is a Browse By group of the Nature Atlas that gathers the mammal orders whose members reproduce by laying eggs rather than giving birth to live young, the monotremes of the order Monotremata, such as the platypus and the echidnas. An entry belongs here when its own cited article describes an order of mammals that lays eggs and still nurses its hatchlings with milk. It excludes the marsupial orders and the placental orders, which bear live young. The group shows the oldest branch of the mammal family tree and lets a reader compare it with the live-bearing lineages in the other groups of this subcategory.