Tag: Snakes

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Can All Snakes Swim?

A review of the evidence and testing species across phylogeny and morphological diversity
G. Fosseries, A. Herrel, R. Godoy-Diana, P. Gaucher, M. Traimond, A. Joris, K. Daoues, A. Gouygou, O. Chateau, H. Gossuin, P. Banzept, C. Banzept, D. Lefebvre, & X. Bonnet
Zoology 126223 (2024).
doi: 10.1016/j.zool.2024.126223

Whether the ancestors of snakes were burrowing, land-dwelling, or marine creatures has led to questions about whether all modern snakes can swim or if this ability varies among different snake groups. As part of Guillaume Fosseries‘ PhD thesis and of the ANR Dragon2 project, led by Xavier Bonnet at the Centre d’Études Biologiques de Chizé (CEBC UMR7372, CNRS, La Rochelle University), we conducted a comprehensive systematic review following PRISMA guidelines, incorporating published literature, personal communications, and website information to examine swimming abilities across snake species. This review found swimming information for only about 11% of all known snake species, with most data coming from aquatic species and very little from burrowing or early-evolved snake groups. To address these significant phylogenetic gaps in our knowledge, we directly tested the swimming capacity of 103 diverse snake species plus 13 other limbless and limbed reptiles. Every single species we examined demonstrated the ability to swim, confirming that this universal swimming ability appears to be a shared trait among many land vertebrates that move by undulating their bodies from side to side. These results suggest that swimming capacity alone cannot help determine the evolutionary origins of snakes, and that future research should focus on measuring swimming performance, efficiency, and technique rather than simply whether snakes can swim at all.

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Form and function of anguilliform swimming: a review

V. Stin, R. Godoy-Diana, X. Bonnet, & A. Herrel
Biological Reviews (2024)
doi: 10.1111/brv.13116

Anguilliform swimmers are long and narrow animals that propel themselves by undulating their bodies. Observations in nature and recent investigations suggest that anguilliform swimming is highly efficient. However, understanding the underlying reasons for the efficiency of this type of locomotion requires interdisciplinary studies spanning from biology to hydrodynamics. Regrettably, these different fields are rarely discussed together, which hinders our ability to understand the repeated evolution of this swimming mode in vertebrates. This review compiles the current knowledge of the anatomical features that drive anguilliform swimming, compares the resulting kinematics across a wide range of anguilliform swimmers, and describes the resulting hydrodynamic interactions using data from both in vivo experiments and computational studies.

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Volumetric velocimetry of the wake of a swimming snake

We describe a method for measuring the 3D vortical structures produced by an anguilliform swimmer using volumetric velocimetry. The wake of freely swimming dice snakes (Natrix tessellata) was quantified, revealing the creation of multiple vortices along the body of the snake due to its undulation. The 3D structure of the vortices generally consisted of paired vortex tubes, some of which were linked together to form a hairpin structure. The observations match predictions from computational fluid dynamic studies of other anguilliform swimmers. Quantitative measurements allowed us to study vortex circulation and size, and global kinetic energy of the flow, which varied with swimming speed, vortex topology and individual characteristics. Our findings provide a baseline for comparing wake structures of snakes with different morphologies and ecologies and investigating the energetic efficiency of anguilliform swimming.


V. Stin, R. Godoy-Diana, X. Bonnet, & A. Herrel. Measuring the 3D wake of swimming snakes (Natrix tessellata) using volumetric velocimetry.
Journal of Experimental Biology, 226, jeb245929 (2023)
doi: 10.1242/jeb.245929

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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”

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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”