2018 Impact factor 1.686
Soft Matter and Biological Physics

EPJ E Highlight - Understanding the evolution of lungs through physical principles




Our respiratory system consists of a bronchial tree designed to transport air through the lungs combined with an alveolar system designed to capture the oxygen. Both are subjected to different type of optimisations. Only tree-like structures, the paper shows, are able to efficiently feed organs above a small size, below which organs are solely fed by diffusion. Specifically, the authors first show that energy losses of fluids during transport are minimised in a tree-like structure of fractal dimension 3. Second, they indicate that this optimised tree is also ‘space-filling’ to optimise proximity to the working alveolae. Third, they show that a system designed to reduce the time spent to transport fluids throughout an organ has the same fractal optimisation.


Similarly, the paper shows that the structure of the alveolar system is indeed optimal to allow efficient transport of oxygen from the air to the blood. This new insight into the lung’s evolutionary process stems from the physical principles underlying the architecture of living systems.

Optimisations and evolution of mammalian respiratory systems. B. Sapoval and M. Filoche (2013), European Physical Journal E 36: 105, DOI 10.1140/epje/i2013-13105-1

F. Graner and F. Sciortino

Cyprien Gay

ISSN (Print Edition): 1292-8941
ISSN (Electronic Edition): 1292-895X

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