What do monotremes have in common with reptiles and birds?

Monotremes, like other mammals, are warm-blooded vertebrate animals with a covering of fur. Their young are nourished with milk.

Other characteristics which monotremes share with other mammals are;

- A flexible neck with seven cervical vertebrae

- Breathe using lungs

- Mammals also show enhanced neocortex development

- Sound is produced by the larynx (a modified region of the trachea)

- limbs are oriented vertically

- The mammalian heart has 4 chambers

- Internal temperature is generally high

- Egg development occurs in the uterus (excluding monotremata)

- They have sweat glands

- A single jaw bone

- Diaphragm

- Three bones for a middle ear

- Give birth to young alive

- Feeds milk to its young

- Has hair on its body