Hydrodynamics of the frontal strike in aquatic snakes

Hydrodynamics of the frontal strike in aquatic snakes: drag, added mass and the consequences for prey capture success

 

M. Segall, A. Herrel & R. Godoy-Diana
Bioinspiration & Biomimetics
14, 036005 (2019)
[doi:10.1088/1748-3190/ab0316]
bioRxiv preprint: https://doi.org/10.1101/411850

Transient locomotion under water is highly constrained by drag and added mass, yet some aquatic snakes catch their prey using a fast forward acceleration, with the mouth opened. These aquatic snakes show a convergence of their head shape in comparison with closely related species that do not forage under water. As both drag and added mass are related to some extent to the shape of the moving object, we explored how shape impacts the hydrodynamic forces applied to the head of a snake during a prey capture event. We compared two 3D- Continue reading “Hydrodynamics of the frontal strike in aquatic snakes”

Hydrodynamic constraints and evolution of aquatic snakes

snakesDoes aquatic foraging impact head shape evolution in snakes ?
M. Segall, R. Cornette, A-C. Fabre, R. Godoy-Diana & A. Herrel
Proceedings of the Royal Society B 283 20161645 (2016).
[doi:10.1098/rspb.2016.1645] PDF file

Evolutionary trajectories are often biased by developmental and historical factors. However, environmental factors can also impose constraints on the evolutionary trajectories of organisms leading to convergence of morphology in similar ecological contexts. The physical properties of water impose strong constraints on aquatic feeding animals by generating pressure waves that can alert prey and potentially push them away from the mouth. These hydrodynamic constraints have resulted in the independent evolution of suction feeding in most groups of secondarily aquatic tetrapods. Despite the fact that snakes cannot use suction, they have invaded the aquatic milieu many times independently. Here, we test whether the aquatic environment has constrained head Continue reading “Hydrodynamic constraints and evolution of aquatic snakes”