Prototropies or Monotremes

Platypus: Example of Prototery Mammal

What they are - biological definition

The prototerias (Prototheria or Monotremata group) are oviparous primitive mammalian animals (laying eggs).

Main Features:

- The embryos of the prototropies develop inside eggs, therefore, outside the female's body.

- Have heart with 4 cavities (chambers).

- Fur covered with hair.

- They have a diaphragm.

- Females have mammary glands and therefore the ability to produce milk to feed the young.

- They are homeothermic mammals (have constant body temperature), ranging between 28 and 32ºC.

- They have 3 bones in the middle ear.

- Teeth are atrophied or missing.

Prototype examples:

- Platypus

- Echidnas (there are five species)

Biological Curiosities:

- The prototeries live mainly in Australia, Tasmania and New Guinea.

- Have a solitary behavior, looking for partners only at the time of mating.

Scientific classification:

Kingdom: Animalia

Philo: Chordata

Class: Mammalia

Subclass: Prototheria