Natural selection of lung’s geometry
vendredi 25 janvier 2019, 11h00 - 12h00
Mammals’ lung is an organ that transports ambient air to and from the air/blood interface, where exchanges of oxygen and carbon dioxide take place. This interface is large, about one hundred square meters in humans, and folded into the thoracic cage. To reach it, the lung’s geometry is shaped as a dichotomous tree. Each branch of that tree is a tube where air is flowing, and each leaves of the tree feeds a portion of the air/blood interface. Successive internalisations and externalisation of a volume of air allow to perform an efficient lung’s ventilation. During this talk, we will focus more specifically on lung’s geometry: we will see how the use of a wide spectra of modelling and mathematical approaches can bring important insights on why and how lung’s geometry could have been selected. We will first show how the efficiency of its function as an organ is related to its geometry, next we will discuss lung’s development, before linking the two into a global and plausible scenario of lung’s geometry selection by evolution.