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Functional morphology of the leg musculature in the marine seal louse: adaptations for high-performance attachment to diving hosts


Abstract

The seal louse (Echinophthirius horridus) is a remarkable example of evolutionary adaptation, thriving as an obligate ectoparasite on deep-diving marine mammals under extreme environmental conditions, including high hydrostatic pressure, extreme drag force, salinity, and fluctuating temperatures. To investigate the anatomical and functional specializations enabling this lifestyle, we compared the leg morphology and musculature of E. horridus with its terrestrial relative, the human head louse (Pediculus humanus capitis), using synchrotron-based 3D microtomography and confocal laser scanning microscopy. Our findings reveal that the seal louse has developed a highly compact and robust leg structure with a fused tibiotarsus, an additional set of leg muscles, and a shortened claw tendon—an unprecedented adaptation among insects. These features allow for greater force transmission and reduced metabolic cost during sustained attachment. Behavioral assays further show that E. horridus can only move effectively on hair-like substrates, underscoring its complete reliance on host fur. These findings suggest a highly specialized muscular control system enabling strong, reliable, and reversible attachment in a challenging aquatic environment.

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The deeper the rounder: body shape variation in lice parasitizing diving hosts

Data availability

All data is provided in the Supplementary Material of the manuscript. Synchrotron data and histological sectioning series90 can be provided upon request or online under: [https://doi.org/10.6084/m9.figshare.28596953.v2] (https:/doi.org/https://doi.org/10.6084/m9.figshare.28596953.v2).

References

  1. Gorb, S.N. (2001) Attachment Devices of Insect Cuticle. 1st edn, Springer Netherlands. 1st edn. Dordrecht, Netherlands: Springer, Dordrecht. https://doi.org/10.1007/0-306-47515-4.

  2. Beutel, R. G. & Gorb, S. N. Ultrastructure of attachment specializations of hexapods (Arthropoda): Evolutionary patterns inferred from a revised ordinal phylogeny. J. Zool. Syst. Evol. Res. 39(4), 177–207. https://doi.org/10.1046/j.1439-0469.2001.00155.x (2001).

    Google Scholar 

  3. Gorb, S. N. Biological attachment devices: exploring nature’s diversity for biomimetics. Philos. Trans. R. Soc. A: Math., Phys. Eng. Sci. 366(1870), 1557–1574. https://doi.org/10.1098/rsta.2007.2172 (2008).

    Google Scholar 

  4. Gorb, S. N. & Beutel, R. Evolution of locomotory attachment pads of hexapods. Naturwissenschaften 88(12), 530–534. https://doi.org/10.1007/s00114-001-0274-y (2001).

    Google Scholar 

  5. Bajerlein, D. et al. To attach or not to attach? The effect of carrier surface morphology and topography on attachment of phoretic. Naturwissenschaften 103(7–8), 61. https://doi.org/10.1007/s00114-016-1385-9 (2016).

    Google Scholar 

  6. Federle, W. & Labonte, D. Dynamic biological adhesion: Mechanisms for controlling attachment during locomotion. Philos. Trans. R. Soc. B: Biol. Sci. 374(1784), 20190199. https://doi.org/10.1098/rstb.2019.0199 (2019).

    Google Scholar 

  7. Li, D., Huson, M. G. & Graham, L. D. Proteinaceous adhesive secretions from insects, and in particular the egg attachment glue of Opodiphthera sp. moths. Arch. Insect Biochem. Physiol.: Publ. Collab. Entomol. Soc. Am. 69(2), 85–105. https://doi.org/10.1002/arch.20267 (2008).

    Google Scholar 

  8. Autumn, K. et al. Adhesive force of a single gecko foot-hair. Nature 405(6787), 681–685. https://doi.org/10.1038/35015073 (2000).

    Google Scholar 

  9. Autumn, K. et al. Evidence for van der Waals adhesion in gecko setae. Proc. Natl. Acad. Sci. 99(19), 12252–12256. https://doi.org/10.1073/pnas.192252799 (2002).

    Google Scholar 

  10. Autumn, K. & Hansen, W. Ultrahydrophobicity indicates a non-adhesive default state in gecko setae. J. Comp. Physiol. A. 192, 1205–1212. https://doi.org/10.1007/s00359-006-0149-y (2006).

    Google Scholar 

  11. Autumn, K. & Peattie, A. M. Mechanisms of adhesion in geckos. Integr. Comp. Biol. 42(6), 1081–1090. https://doi.org/10.1093/icb/42.6.1081 (2002).

    Google Scholar 

  12. Badge, I. et al. The role of surface chemistry in adhesion and wetting of gecko toe pads. Sci. Rep. 4(1), 6643. https://doi.org/10.1038/srep06643 (2014).

    Google Scholar 

  13. Maderson, P. F. A. Keratinized epidermal derivatives as an aid to climbing in gekkonid lizards. Nature 203(4946), 780–781. https://doi.org/10.1038/203780a0 (1964).

    Google Scholar 

  14. Mitchell, C. T. et al. The effect of substrate wettability and modulus on gecko and gecko-inspired synthetic adhesion in variable temperature and humidity. Sci. Rep. 10(1), 19748. https://doi.org/10.1038/s41598-020-76484-6 (2020).

    Google Scholar 

  15. Ruibal, R. & Ernst, V. The structure of the digital setae of lizards. J. Morphol. 117(3), 271–293. https://doi.org/10.1002/jmor.1051170302 (1965).

    Google Scholar 

  16. Williams, E. E. & Peterson, J. A. Convergent and alternative designs in the digital adhesive pads of scincid lizards. Science 215(4539), 1509–1511. https://doi.org/10.1126/science.215.4539.1509 (1982).

    Google Scholar 

  17. Higham, T. E. & Russell, A. P. Geckos running with dynamic adhesion: Towards integration of ecology, energetics and biomechanics. J. Exp. Biol. 228, 247980. https://doi.org/10.1242/jeb.247980 (2025).

    Google Scholar 

  18. Russell, A. P. The morphological basis of weight-bearing in the scansors of the tokay gecko (Reptilia: Sauria). Can. J. Zool. 64(4), 948–955. https://doi.org/10.1139/z86-144 (1986).

    Google Scholar 

  19. Chen, Y. et al. Underwater attachment using hairs: The functioning of spatula and sucker setae from male diving beetles. J. R. Soc. Interface 11(97), 20140273. https://doi.org/10.1098/rsif.2014.0273 (2014).

    Google Scholar 

  20. Kampowski, T. et al. Exploring the attachment of the Mediterranean medicinal leech (Hirudo verbana) to porous substrates. J. R. Soc. Interface 17(168), 20200300. https://doi.org/10.1098/rsif.2020.0300 (2020).

    Google Scholar 

  21. Kier, W. M. & Smith, A. M. The structure and adhesive mechanism of octopus suckers. Integr. Comp. Biol. 42(6), 1146–1153. https://doi.org/10.1093/icb/42.6.1146 (2002).

    Google Scholar 

  22. Smith, A. M. Negative pressure generated by octopus suckers: a study of the tensile strength of water in nature. J. Exp. Biol. 157(1), 257–271. https://doi.org/10.1242/jeb.157.1.257 (1991).

    Google Scholar 

  23. Smith, A. M. Cephalopod sucker design and the physical limits to negative pressure. J. Exp. Biol. 199(4), 949–958. https://doi.org/10.1242/jeb.199.4.949 (1996).

    Google Scholar 

  24. Busshardt, P. & Gorb, S. N. Walking on smooth and rough ground: Activity and timing of the claw retractor muscle in the beetle Pachnoda marginata peregrina (Coleoptera, Scarabaeidae). J. Exp. Biol. 216(2), 319–328. https://doi.org/10.1242/jeb.075614 (2013).

    Google Scholar 

  25. Dunlop, J. A. Movements of scopulate claw tufts at the tarsus tip of a tarantula spider. Netherlands J. Zool. 45(3–4), 513–520 (1994).

    Google Scholar 

  26. Federle, W. et al. Biomechanics of the movable pretarsal adhesive organ in ants and bees. Proc. Natl. Acad. Sci. 98(11), 6215–6220. https://doi.org/10.1073/pnas.111139298 (2001).

    Google Scholar 

  27. Frantsevich, L. & Gorb, S. Structure and mechanics of the tarsal chain in the hornet, Vespa crabro (Hymenoptera: Vespidae): implications on the attachment mechanism. Arthropod Struct. Dev. 33(1), 77–89. https://doi.org/10.1016/j.asd.2003.10.003 (2004).

    Google Scholar 

  28. Frazier, S. F. et al. Elasticity and movements of the cockroach tarsus in walking. J. Comp. Physiol. – A Sensory, Neural, Behav. Physiol. 185(2), 157–172. https://doi.org/10.1007/s003590050374 (1999).

    Google Scholar 

  29. Heming, B. S. Functional morphology of the thysanopteran pretarsus. Can. J. Zool. 49(1), 91–108. https://doi.org/10.1139/z71-014 (1971).

    Google Scholar 

  30. Niederegger, S. & Gorb, S. N. Tarsal movements in flies during leg attachment and detachment on a smooth substrate. J. Insect Physiol. 49(6), 611–620. https://doi.org/10.1016/S0022-1910(03)00048-9 (2003).

    Google Scholar 

  31. Gorb, S. N. et al. The insect unguitractor plate in action: Force transmission and the micro CT visualizations of inner structures. J. Insect Physiol. 117, 103908. https://doi.org/10.1016/j.jinsphys.2019.103908 (2019).

    Google Scholar 

  32. Gorb, S. N., Gorb, E. V. & Kastner, V. Scale effects on the attachment pads and friction forces in syrphid flies (Diptera, Syrphidae). J. Exp. Biol. 204(8), 1421–1431. https://doi.org/10.1242/jeb.204.8.1421 (2001).

    Google Scholar 

  33. Büscher, T. H. et al. The exceptional attachment ability of the ectoparasitic bee louse Braula coeca (Diptera, Braulidae) on the honeybee. Physiol. Entomol. 47(2), 83–95. https://doi.org/10.1111/PHEN.12378 (2022).

    Google Scholar 

  34. Petersen, D. S. et al. Holding tight to feathers – structural specializations and attachment properties of the avian ectoparasite Crataerina pallida (Diptera, Hippoboscidae). J. Exp. Biol. 221(13), jeb179242. https://doi.org/10.1242/jeb.179242 (2018).

    Google Scholar 

  35. Preuss, A. et al. Attachment performance of the ectoparasitic seal louse Echinophthirius horridus. Commun. Biol. 7(1), 36. https://doi.org/10.1038/s42003-023-05722-0 (2024).

    Google Scholar 

  36. Bush, A. O. et al. Parasitism: The diversity and ecology of animal parasites (Cambridge University Press, Cambridge, 2001).

    Google Scholar 

  37. Kim, K. C. Coevolution of parasitic arthropods and mammals (Wiley-Interscience, 1985).

    Google Scholar 

  38. Anderson, R. C. ‘Host-parasite relations and evolution of the Metastrongyloidea (Nematoda)’, Memoires du Museum National d’Histoire Naturelle. Serie A. Zoologie 123, 129–132. https://doi.org/10.5281/zenodo.16007555 (1982).

    Google Scholar 

  39. Raga, J. A. et al. Parasites. In Encyclopedia of Marine Mammals (eds Perrin, W. F. et al.) 821–830 (Academic Press, London, UK, 2009). https://doi.org/10.1016/B978-0-12-373553-9.00193-0.

    Google Scholar 

  40. Rybczynski, N., Dawson, M. R. & Tedford, R. H. A semi-aquatic Arctic mammalian carnivore from the Miocene epoch and origin of Pinnipedia. Nature 458(7241), 1021–1024. https://doi.org/10.1038/nature07985 (2009).

    Google Scholar 

  41. Durden, L. A. & Musser, G. G. The sucking lice (Insecta, Anoplura) of the world – a taxonomic checklist with records of mammalian hosts and geographical distributions. Bull. Am. Mus. Nat. Hist. 218, 1–90 (1994).

    Google Scholar 

  42. Grzimek, B. Grzimek’s encyclopedia of mammals (McGraw-Hill Publishing Company, 1990).

    Google Scholar 

  43. Leonardi, M. S. & Palma, R. L. Review of the systematics, biology and ecology of lice from pinnipeds and river otters (Insecta: Phthiraptera: Anoplura: Echinophthiriidae). Zootaxa 3630(3), 445–466. https://doi.org/10.11646/zootaxa.3630.3.3 (2013).

    Google Scholar 

  44. Eguchi, T. & Harvey, J. ‘Diving behavior of the Pacific harbor seal (Phoca vitulina richardii) in Monterey Bay California. Mar. Mamm. Sci. 21, 283–295. https://doi.org/10.1111/j.1748-7692.2005.tb01228.x (2006).

    Google Scholar 

  45. Frost, K. J., Simpkins, M. A. & Lowry, L. F. Diving behavior of subadult and adult harbor seals in Prince William Sound, Alaska. Mar. Mamm. Sci. 17(4), 813–834. https://doi.org/10.1111/j.1748-7692.2001.tb01300.x (2001).

    Google Scholar 

  46. Gjertz, I., Lydersen, C. & Wiig, Ø. Distribution and diving of harbour seals (Phoca vitulina) in Svalbard. Polar Biol. 24(3), 209–214. https://doi.org/10.1007/s003000000197 (2001).

    Google Scholar 

  47. Hastings, K. K. et al. Regional differences in diving behavior of harbor seals in the Gulf of Alaska. Can. J. Zool. 82(11), 1755–1773. https://doi.org/10.1139/z04-145 (2004).

    Google Scholar 

  48. Kolb, P. M. A harbor seal Phoca vitulina richardsi, taken from a sablefish trap. California Fish Game 68, 123–124 (1982).

    Google Scholar 

  49. Rosing-Asvid, A. et al. Deep diving harbor seals (Phoca vitulina) in South Greenland: movements, diving, haul-out and breeding activities described by telemetry. Polar Biol. 43(4), 359–368. https://doi.org/10.1007/s00300-020-02639-w (2020).

    Google Scholar 

  50. Dehnhardt, G., Mauck, B. & Hyvärinen, H. Ambient temperature does not affect the tactile sensitivity of mystacial vibrissae in harbour seals. J. Exp. Biol. 201(22), 3023–3029. https://doi.org/10.1242/jeb.201.22.3023 (1998).

    Google Scholar 

  51. Mauck, B. et al. Thermal windows on the trunk of hauled-out seals: Hot spots for thermoregulatory evaporation?. J. Exp. Biol. 206(10), 1727–1738. https://doi.org/10.1242/jeb.00348 (2003).

    Google Scholar 

  52. Hansen, S. & Lavigne, D. M. Ontogeny of the thermal limits in the harbor seal (Phoca vitulina). Physiol. Zool. 70(1), 85–92. https://doi.org/10.1086/639549 (1997).

    Google Scholar 

  53. Watts, P. Thermal constraints on hauling out by harbor seals (Phoca vitulina). Can. J. Zool. 70, 553–560. https://doi.org/10.1139/z92-083 (2011).

    Google Scholar 

  54. Leonardi, M. S. et al. Under pressure: the extraordinary survival of seal lice in the deep sea. J. Exp. Biol. 223(17), jeb226811. https://doi.org/10.1242/jeb.226811 (2020).

    Google Scholar 

  55. Williams, T. M. & Kooyman, G. L. Swimming performance and hydrodynamic characteristics of harbor seals Phoca vitulina. Physiol. Zool. 58(5), 576–589. https://doi.org/10.1086/physzool.58.5.30158584 (1985).

    Google Scholar 

  56. Preuss, A., Gorb, S.N., et al. (2025) ‘Role of the Setae in an Ectoparasitic Seal Louse in Reducing Surface Drag: Numerical Modeling Approach’, Advanced Theory and Simulations, p. e00429. https://doi.org/10.1002/adts.202500429.

  57. Herzog, I. et al. Heartworm and seal louse: Trends in prevalence, characterisation of impact and transmission pathways in a unique parasite assembly on seals in the North and Baltic Sea. Int. J. Parasitol.: Parasites Wildlife 23, 100898. https://doi.org/10.1016/j.ijppaw.2023.100898 (2024).

    Google Scholar 

  58. Herzog, I., Siebert, U. & Lehnert, K. High prevalence and low intensity of Echinophthirius horridus infection in seals revealed by high effort sampling. Sci. Rep. 14(1), 14258. https://doi.org/10.1038/s41598-024-64890-z (2024).

    Google Scholar 

  59. Siebert, U. et al. Pathological findings in harbour seals (Phoca vitulina): 1996–2005. J. Comp. Pathol. 137(1), 47–58. https://doi.org/10.1016/j.jcpa.2007.04.018 (2007).

    Google Scholar 

  60. Michels, J. & Gorb, S. N. Detailed three-dimensional visualization of resilin in the exoskeleton of arthropods using confocal laser scanning microscopy. J. Microsc. 245(1), 1–16. https://doi.org/10.1111/j.1365-2818.2011.03523.x (2012).

    Google Scholar 

  61. Andersen, S. O. Biochemistry of insect cuticle. Annu. Rev. Entomol. 24(1), 29–59. https://doi.org/10.1146/annurev.en.24.010179.000333 (1979).

    Google Scholar 

  62. Büsse, S. & Gorb, S. N. Material composition of the mouthpart cuticle in a damselfly larva (Insecta: Odonata) and its biomechanical significance. R. Soc. Open Sci. 5(6), 172117. https://doi.org/10.1098/rsos.172117 (2018).

    Google Scholar 

  63. Josten, B., Gorb, S. N. & Büsse, S. The mouthparts of the adult dragonfly Anax imperator (Insecta: Odonata), functional morphology and feeding kinematics. J. Morphol. 283(9), 1163–1181. https://doi.org/10.1002/jmor.21497 (2022).

    Google Scholar 

  64. Vincent, J. F. V. Arthropod cuticle: a natural composite shell system. Compos. A Appl. Sci. Manuf. 33(10), 1311–1315. https://doi.org/10.1016/S1359-835X(02)00167-7 (2002).

    Google Scholar 

  65. Cecilia, A. et al. The IMAGE beamline at the KIT light source. J. Synchrotron Radiat. 32(4), 1036–1051. https://doi.org/10.1107/s1600577525003777 (2025).

    Google Scholar 

  66. Douissard, P. A. et al. A versatile indirect detector design for hard X-ray microimaging. J. Instrum. 7(9), P09016. https://doi.org/10.1088/1748-0221/7/09/P09016 (2012).

    Google Scholar 

  67. Vogelgesang, M. et al. Real-time image-content-based beamline control for smart 4D X-ray imaging. J. Synchrotron Radiat. 23(5), 1254–1263. https://doi.org/10.1107/S1600577516010195 (2016).

    Google Scholar 

  68. Vogelgesang, M. et al. (2012) ‘UFO: A Scalable GPU-based Image Processing Framework for On-line Monitoring’, in Proceedings of HPCC-ICESS., pp. 824–829. https://doi.org/10.1109/HPCC.2012.116.

  69. Faragó, T. et al. Tofu: A fast, versatile and user-friendly image processing toolkit for computed tomography. J. Synchrotron Radiat. 29, 916–927. https://doi.org/10.1107/S160057752200282X (2022).

    Google Scholar 

  70. Gray, P. T. A., Mill, P. J. & Dodd, J. M. ‘The musculature of the prothoracic legs and its innervation in Hierodula membranacea (Mantidea)’. Philos. Trans. R. Soc. London B, Biol. Sci. 309(1140), 479–503. https://doi.org/10.1098/rstb.1985.0094 (1997).

    Google Scholar 

  71. Preuss, A. et al. The ectoparasitic seal louse, Echinophthirius horridus, relies on a sealed tracheal system and spiracle closing apparatus for underwater respiration. Commun. Biol. 8(1), 1–14. https://doi.org/10.1038/s42003-025-08285-4 (2025).

    Google Scholar 

  72. Leonardi, M. S. et al. The deeper the rounder: body shape variation in lice parasitizing diving hosts. Sci. Rep. 14(1), 1–10. https://doi.org/10.1038/s41598-024-71541-w (2024).

    Google Scholar 

  73. Appel, E. et al. Ultrastructure of dragonfly wing veins: Composite structure of fibrous material supplemented by resilin. J. Anat. 227(4), 561–582. https://doi.org/10.1111/joa.12362 (2015).

    Google Scholar 

  74. Vaughan, J. A. & Azad, A. F. Patterns of erythrocyte digestion by bloodsucking insects: constraints on vector competence. J. Med. Entomol. 30(1), 214–216. https://doi.org/10.1093/jmedent/30.1.214 (1993).

    Google Scholar 

  75. Waniek, P. J. The digestive system of human lice: Current advances and potential applications. Physiol. Entomol. 34(3), 203–210. https://doi.org/10.1111/j.1365-3032.2009.00681.x (2009).

    Google Scholar 

  76. Leonardi, M. S. et al. Host-parasite coevolution leads to underwater respiratory adaptations in extreme diving insects, seal lice (Lepidophthirus macrorhini). Communications Biology 8(1), 1–11. https://doi.org/10.1038/s42003-025-08306-2 (2025).

    Google Scholar 

  77. Soler Cruz, M. D. & Martín Mateo, M. P. Scanning electron microscopy of legs of two species of sucking lice (Anoplura: Phthiraptera). Micron 40(3), 401–408. https://doi.org/10.1016/j.micron.2008.10.001 (2009).

    Google Scholar 

  78. Wolfram, L. J. Human hair: A unique physicochemical composite. J. Am. Acad. Dermatol. 48(6), S106–S114. https://doi.org/10.1067/mjd.2003.276 (2003).

    Google Scholar 

  79. Aibekova, L. et al. The skeletomuscular system of the mesosoma of Formica rufa Workers (Hymenoptera: Formicidae). Insect Systematics and Diversity 6(2), 1–26. https://doi.org/10.1093/isd/ixac002 (2022).

    Google Scholar 

  80. Woodworth, C. W. The leg tendons of insects. Am. Nat. 42(499), 452–456. https://doi.org/10.1086/278953 (1908).

    Google Scholar 

  81. Lee, S. S. M. & Piazza, S. J. Built for speed: Musculoskeletal structure and sprinting ability. J. Exp. Biol. 212(22), 3700–3707. https://doi.org/10.1242/jeb.031096 (2009).

    Google Scholar 

  82. Baxter, J. R. et al. Ankle joint mechanics and foot proportions differ between human sprinters and non-sprinters. Proc. R. Soc. B: Biol. Sci. 279(1735), 2018–2024. https://doi.org/10.1098/rspb.2011.2358 (2012).

    Google Scholar 

  83. Fletcher, J. R. & MacIntosh, B. R. Achilles tendon strain energy in distance running: consider the muscle energy cost. J. Appl. Physiol. 118(2), 193–199. https://doi.org/10.1152/japplphysiol.00732.2014 (2015).

    Google Scholar 

  84. MacIntosh, B.R. and Holash, R.J. (2000) ‘Power output and force-velocity properties of muscle’, In: B.M. Nigg, B.R. MacIntosh, and J. Mester (Eds) Biomechanics and biology of movement. Human Kinetics. Champaign, Illinois (US): Human Kinetics, pp. 193–210.

  85. Kim, K. C. Ecology and morphological adaptations of the sucking lice on the nothern fur seal. J. Cons. Int. Explor. Mer. 169, 504–515 (1975).

    Google Scholar 

  86. Koštál, V. Eco-physiological phases of insect diapause. J. Insect Physiol. 52(2), 113–127. https://doi.org/10.1016/j.jinsphys.2005.09.008 (2006).

    Google Scholar 

  87. Leonardi, M. S. & Lazzari, C. R. Uncovering deep mysteries: The underwater life of an amphibious louse. J. Insect Physiol. 71, 164–169. https://doi.org/10.1016/j.jinsphys.2014.10.016 (2014).

    Google Scholar 

  88. Gorb, S. N. Design of insect unguitractor apparatus. J. Morphol. 230(2), 219–230. https://doi.org/10.1002/(SICI)1097-4687(199611)230:2%3c219::AID-JMOR8%3e3.0.CO;2-B (1996).

    Google Scholar 

  89. Hörger, V., Labisch, S. & Dirks, J.-H. Biomimetic tag attachment inspired by the seal louse. Bioinspiration Biomimetics 20(6), 066015. https://doi.org/10.1088/1748-3190/adfbb8 (2025).

    Google Scholar 

  90. Preuss, A., Schwaha, T., et al. (2025a) ‘Nano-CT data and histological sections of Pediculus humanus capitis and Echinophthirius horridus’, figshare. https://doi.org/10.6084/m9.figshare.28596953.v2.

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Acknowledgements

We express our profound gratitude to Dr. Thies Büscher, Dr. Helen Gorges, Fabian Bäumler, Julian Thomas, Simon Züger, and Benedikt Josten for their invaluable guidance and assistance throughout this study. We also extend our appreciation to Esther Appel and Dr. Alexander Kovalev for their technical support during the experiments. We would also like to thank the TiHo Hannover, especially Dr. Insa Herzog and Dr. Kristina Lehnert, for supplying us with seal louse samples. Additionally, we acknowledge Marta Tischer for generously supplying head louse samples preserved in ethanol. We are indebted to Dr. Angelica Cecilia for her assistance during beamtime and to Dr. Tomáš Faragó for his work on tomographic reconstructions. We express our gratitude to the KIT Light Source for providing instruments at their beamlines and to the Institute for Beam Physics and Technology (IBPT) for operating the storage ring, the Karlsruhe Research Accelerator (KARA). Furthermore, we acknowledge the funding provided to S.N.G. by the grant GO 995 46-1 from the German Science Foundation (DFG) within the Special Priority Program (SPP 2332) “Physics of Parasitism.” The funders had no involvement in the study design, data collection and analysis, publication decisions, or manuscript preparation.

Funding

Open Access funding enabled and organized by Projekt DEAL. Funding for this study was granted to S.N.G by the German Science Foundation (DFG) under grant number GO 995 46–1, as part of the Special Priority Program (SPP 2332) known as “Physics of Parasitism”.

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Authors and Affiliations

Authors

Contributions

A.P., S.N.G.—Conceptualization; A.P., T.v.d.K., S.N.G.—Data curation; A.P., T.v.d.K., S.N.G.—Formal analysis; S.N.G.—Funding acquisition; A.P., T.v.d.K., L.O.—Investigation; A.P., T.v.d.K., E.H., M.Z., S.N.G.—Methodology; S.N.G.—Project administration; A.P.—Software; S.N.G.—Supervision; A.P., S.N.G.—Validation; A.P., L.O.—Visualization; A.P.—Writing—original draft; T.v.d.K., E.H., M.Z., L.O., S.N.G.—Writing – review & editing.

Corresponding author

Correspondence to
Anika Preuss.

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Competing interests

The authors declare no competing interests.

Ethical approval

Ethical review and approval were not required for this study, as all host animals were either found dead, died naturally, or were euthanized on welfare grounds, with none being killed specifically for this research. The authors were not involved in the euthanasia of the hosts, which was carried out by certified seal rangers for reasons unrelated to this study. All regulations regarding animal use were strictly followed.

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Preuss, A., van de Kamp, T., Hamann, E. et al. Functional morphology of the leg musculature in the marine seal louse: adaptations for high-performance attachment to diving hosts.
Sci Rep (2025). https://doi.org/10.1038/s41598-025-32804-2

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  • DOI: https://doi.org/10.1038/s41598-025-32804-2

Keywords

  • Parasitism
  • Seal louse
  • Human head louse
  • Marine mammals
  • Biomechanics
  • Extremities
  • Skeleton-muscle organization

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