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In the past few years we have unfortunately had several reminders of the ability of a particular type of ocean wave—a tsunami—to devastate coastal areas. The Indian Ocean tsunami of 2004, in particular, was one of the largest natural disasters of past decades in terms of the number of people killed. The name of this phenomenon, tsunami, is possibly the only term that has entered the physics lexicon from Japanese. We use Japanese and Western sources to document historical tsunami in Europe and Japan, the birth of the scientific understanding of tsunami, and how the Japanese term came to be adopted in English.

We address with fluid-dynamical simulations using direct numerical techniques three important and fundamental questions with respect to fluid flow within the mouse node and left–right development. First, we consider the differences between what is experimentally observed when assessing cilium-induced fluid flow in the mouse node in vitro and what is to be expected in vivo. The distinction is that in vivo, the leftward fluid flow across the mouse node takes place within a closed system and is consequently confined, while this is no longer the case on removing the covering membrane and immersing the embryo in a fluid-filled volume to perform in vitro experiments. Although there is a central leftward flow in both instances, we elucidate some important distinctions about the closed in vivo situation. Second, we model the movement of the newly discovered nodal vesicular parcels (NVPs) across the node and demonstrate that the flow should indeed cause them to accumulate on the left side of the node, as required for symmetry breaking. Third, we discuss the rupture of NVPs. Based on the biophysical properties of these vesicles, we argue that the morphogens they contain are likely not delivered to the surrounding cells by their mechanical rupture either by the cilia or the flow, and rupture must instead be induced by an as yet undiscovered biochemical mechanism.