Alessandro Giuliani

Stability/Flexibility: the tightly coupled homeostasis generator is at the same time the driver of change

Alessandro Giuliani

Environment and Health Department. Istituto Superiore di Sanità, Roma, Italy

e-mail: alessandro.giuliani@iss.it

There is no Flexibility without Stability and no Stability without Flexibility: this is a crucial feature common to any system interacting with its environment. This tight link between two apparently opposite features is widely recognized and is the basic pillar of physiological control since Claude Bernard definition of homeostasis in the second half of XIX century. On the contrary, the other side of the coin, i.e. that the escape from a stable attractor state initiating a transition is a consequence of the same homeostasis mechanisms is largely overlooked. Here I will try to give a proof-of-concept of the relation existing between homeostasis and state change at all the levels of biological organization. The ‘principles’ allowing shape changes of Waddington landscape going from protein dynamics to psychotherapy passing by cell differentiation dynamics show many remarkable similarities allowing to foresee a (still to come) unified ‘biological statistical mechanics’.