Soft-tissue evidence for homeothermy and crypsis in a Jurassic ichthyosaur

Research output: Contribution to journalArticle


title = "Soft-tissue evidence for homeothermy and crypsis in a Jurassic ichthyosaur",
abstract = "Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales. Here we show that this resemblance is more than skin deep. We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius. Our analyses recovered still-flexible remnants of the original scaleless skin, which comprises morphologically distinct epidermal and dermal layers. These are underlain by insulating blubber that would have augmented streamlining, buoyancy and homeothermy. Additionally, we identify endogenous proteinaceous and lipid constituents, together with keratinocytes and branched melanophores that contain eumelanin pigment. Distributional variation of melanophores across the body suggests countershading, possibly enhanced by physiological adjustments of colour to enable photoprotection, concealment and/or thermoregulation. Convergence of ichthyosaurs with extant marine amniotes thus extends to the ultrastructural and molecular levels, reflecting the omnipresent constraints of their shared adaptation to pelagic life.",
author = "Johan Lindgren and Peter Sj{\"o}vall and Volker Thiel and Wenxia Zheng and Shosuke Ito and Kazumasa Wakamatsu and Rolf Hauff and Kear, {Benjamin P.} and Anders Engdahl and Carl Alwmark and Eriksson, {Mats E.} and Martin Jarenmark and Sven Sachs and Ahlberg, {Per E.} and Federica Marone and Takeo Kuriyama and Ola Gustafsson and Per Malmberg and Aur{\'e}lien Thomen and Irene Rodr{\'i}guez-Meizoso and Per Uvdal and Makoto Ojika and Schweitzer, {Mary H.}",
year = "2018",
doi = "10.1038/s41586-018-0775-x",
language = "English",
volume = "564",
pages = "359--365",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "7736",