Know about The only mammal who lays eggs

The duck-billed platypus and four species of echidna, commonly called spiny anteaters, are the only five monotreme species that are still extant. Only Australia and New Guinea are home to all of them. Today, monotremes are not a particularly diversified group, and until recently, little fossil evidence was available.

Similar to birds and reptiles, monotremes lay eggs instead of giving birth live, which makes them quite primitive for mammals in certain respects. Modern adult monotremes lack teeth, and they are rather derived in a number of other ways, including having highly modified snouts or beaks. However, monotremes share characteristics with other mammals, including a single lower jaw bone, three middle ear bones, high metabolic rates, hair, and the ability to make milk to feed their young.

Monotreme’s inception time and location are still mostly unknown. Although a Paleocene platypus tooth (Monotrematum) was recently recovered from Argentina (Pascual et al. 1992), the majority of fossil monotremes have been discovered in Australia, indicating that they were formerly prevalent throughout southern Gondwana.

Because monotremes, like birds and reptiles, lay eggs rather than give birth live, they are somewhat quite primitive for mammals. Modern adult monotremes lack teeth, and they are rather derived in a number of other ways, including having highly modified snouts or beaks. However, monotremes share characteristics with other mammals, including a single lower jaw bone, three inner ear bones, high metabolic rates, hair, and the ability to make milk to feed their young.