NEET BIOLOGY

Detailed explanation-1: -There are only five living monotreme species: the duck-billed platypus and four species of echidna (also known as spiny anteaters).

Detailed explanation-2: -Along with echidnas, platypus are grouped in a separate order of mammals known as monotremes, which are distinguished from all other mammals because they lay eggs. The platypus and echidna have both survived by occupying ecological niches.

Detailed explanation-3: -Eggs and Lactation in Monotremes Monotreme eggs have a leathery shell, like the eggs of reptiles. The eggs are retained inside the mother’s body for at least a couple of weeks. During that time, the mother provides the eggs with nutrients. Platypus females lay their eggs in a burrow.

Detailed explanation-4: -Only two kinds of egg-laying mammals are left on the planet today-the duck-billed platypus and the echidna, or spiny anteater.

Detailed explanation-5: -The monotremes are a group of highly specialised egg-laying predatory mammals, containing the platypus and echidnas. There are only five living species of monotreme, contained within two families: Family Ornithorhynchidae: the platypus, a single species in a single genus, Ornithorhynchus anatinus.