Physics and Biology of Morphogenesis

One hundred years ago, D’Arcy Thompson – a nineteenth century polymath, working at the turn of the twentieth century – wrote a monograph, “On Growth and Form”, in which he pondered the geometry of living forms and how it emerges in the process of Morphogenesis. Thompson was ahead of his time. Since then, progress of Developmental Biology and Molecular Genetics uncovered many if not most of key genes and molecules involved in Morphogenesis, yet Thompson’s agenda of understanding how developmental processes actually specify the geometry of tissues, limbs and organs is far from complete. A particular challenge is to bridge the gap between microscopic scales, where molecular mechanisms operate, and the macroscopic scales of animal “shape and form”. This challenge offers much for a Physicist to think about. This talk will focus in particular on the mechanical aspects of morphogenesis i) examining the role of mechanical stress in regulation of growth and ii) seeking a quantitative understanding of tissue flows observed in morphogenesis. At the interface of Physics and Biology we will find some new biology and new physics.