What qualifies an animal as a monotreme?
A monotreme is a mammal that lays eggs.  This is uncommon as there are only two mammals, the echidnas and platypus, that do so.  The majority of mammals give placenta birth, with another minority of mammals, known as marsupials, give birth to a fetus-like embryo which is dependent of mother's teat to provide nourishment until fully developed.
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.
### Instruction: What qualifies an animal as a monotreme?
### Input: 
### Response: A monotreme is a mammal that lays eggs.  This is uncommon as there are only two mammals, the echidnas and platypus, that do so.  The majority of mammals give placenta birth, with another minority of mammals, known as marsupials, give birth to a fetus-like embryo which is dependent of mother's teat to provide nourishment until fully developed.