title: Adaptation to life in aeolian sand: how the sandfish lizard, Scincus scincus, prevents sand particles from entering its lungs.
abstract: The sandfish lizard, Scincus scincus (Squamata: Scincidae), spends nearly its whole life in aeolian sand and only comes to the surface for foraging, defecating and mating. It is not yet understood how the animal can respire without sand particles entering its respiratory organs when buried under thick layers of sand. In this work, we integrated biological studies, computational calculations and physical experiments to understand this phenomenon. We present a 3D model of the upper respiratory system based on a detailed histological analysis. A 3D-printed version of this model was used in combination with characteristic ventilation patterns for computational calculations and fluid mechanics experiments. By calculating the velocity field, we identified a sharp decrease in velocity in the anterior part of the nasal cavity where mucus and cilia are present. The experiments with the 3D-printed model validate the calculations: particles, if present, were found only in the same area as suggested by the calculations. We postulate that the sandfish has an aerodynamic filtering system; more specifically, that the characteristic morphology of the respiratory channel coupled with specific ventilation patterns prevent particles from entering the lungs.
authors.affiliation: Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenbergerstraße 69, Linz 4040, Austria anna.stadler@jku.at.
authors.forename: Anna T
authors.identifier: 0000-0001-8253-4396
authors.initials: AT
authors.lastname: Stadler
authors.affiliation: Institute of Biology II, RWTH Aachen University, Worringerweg 3, Aachen 52074, Germany.|IRNAS, Drevesniška 25, Rače 2327, Slovenia.
authors.forename: Boštjan
authors.initials: B
authors.lastname: Vihar
authors.affiliation: Institute of Biology II, RWTH Aachen University, Worringerweg 3, Aachen 52074, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Günther
authors.affiliation: Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenbergerstraße 69, Linz 4040, Austria.
authors.forename: Michaela
authors.initials: M
authors.lastname: Huemer
authors.affiliation: Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenbergerstraße 69, Linz 4040, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Riedl
authors.affiliation: Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenbergerstraße 69, Linz 4040, Austria.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Shamiyeh
authors.affiliation: Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenbergerstraße 69, Linz 4040, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Mayrhofer
authors.affiliation: Zoologisches Forschungsmuseum Alexander Koenig (ZFMK), Adenauerallee 160, Bonn 53 11 3, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Böhme
authors.affiliation: Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenbergerstraße 69, Linz 4040, Austria.
authors.forename: Werner
authors.initials: W
authors.lastname: Baumgartner
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D003889:Desert Climate; D045853:Exhalation / Q000502:physiology; D057446:Hydrodynamics; D021621:Imaging, Three-Dimensional; D001239:Inhalation / Q000502:physiology; D008116:Lizards / Q000502:physiology*; D008168:Lung / Q000033:anatomy & histology / Q000502:physiology*; D008953:Models, Anatomic; D012987:Soil; D013990:Tidal Volume / Q000502:physiology
chemical_list: D012987:Soil
keywords: Calculation; Particle flow; Respiration; Scincus scincus