The Mammals class is a thriving group of vertebrates. Explain what aromorphoses have allowed them to achieve biological progress.

1) four-chamber heart and complete separation of arterial and venous blood;
2) the presence of hair;
3) high and constant body temperature, thermoregulation mechanisms;
4) live birth and feeding offspring with milk;
5) a high level of organization of the central nervous system, complex forms of behavior (developed cerebral cortex)