An ancestral hard-shelled sea turtle with a mosaic of soft skin and scutesShow others and affiliations
2022 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 12, no 1, article id 22655
Article in journal (Refereed) Published
Abstract [en]
The transition from terrestrial to marine environments by secondarily aquatic tetrapods necessitates a suite of adaptive changes associated with life in the sea, e.g., the scaleless skin in adult individuals of the extant leatherback turtle. A partial, yet exceptionally preserved hard-shelled (Pan-Cheloniidae) sea turtle with extensive soft-tissue remains, including epidermal scutes and a virtually complete flipper outline, was recently recovered from the Eocene Fur Formation of Denmark. Examination of the fossilized limb tissue revealed an originally soft, wrinkly skin devoid of scales, together with organic residues that contain remnant eumelanin pigment and inferred epidermal transformation products. Notably, this stem cheloniid—unlike its scaly living descendants—combined scaleless limbs with a bony carapace covered in scutes. Our findings show that the adaptive transition to neritic waters by the ancestral pan-chelonioids was more complex than hitherto appreciated, and included at least one evolutionary lineage with a mosaic of integumental features not seen in any living turtle. © 2022, The Author(s).
Place, publisher, year, edition, pages
Nature Research , 2022. Vol. 12, no 1, article id 22655
Keywords [en]
animal, epidermis, evolution, reptile, skin, turtle, Animals, Biological Evolution, Reptiles, Turtles
National Category
Evolutionary Biology
Identifiers
URN: urn:nbn:se:ri:diva-62576DOI: 10.1038/s41598-022-26941-1Scopus ID: 2-s2.0-85145372322OAI: oai:DiVA.org:ri-62576DiVA, id: diva2:1729419
Note
Funding details: 642-2014-3773; Funding details: Lunds Universitet; Funding details: Vetenskapsrådet, VR; Funding text 1: Ola Gustafsson prepared samples for TEM and assisted during the analyses. Miriam Heingård assisted during the ToF-SIMS analyses, while Carl Alwmark helped out during the FEG-SEM investigation. Maria Mostadius gave us access to extant testudine material in the collections at the Biological Museum, Lund University. Daniel Johansson provided access to modern turtle skins in the herpetological collection at the Zoological Museum in Copenhagen, Denmark. Raffael Ernst and Markus Auer provided images of Carettochelys skin from the herpetological collection at the Senckenberg Museum in Dresden, Germany. Lars Skou Olsen provided information on resident testudines housed in the collections at the National Aquarium of Denmark. Financial support was provided by a Grant for Distinguished Young Researchers (642-2014-3773; Swedish Research Council) to J.L.; Funding text 2: Ola Gustafsson prepared samples for TEM and assisted during the analyses. Miriam Heingård assisted during the ToF-SIMS analyses, while Carl Alwmark helped out during the FEG-SEM investigation. Maria Mostadius gave us access to extant testudine material in the collections at the Biological Museum, Lund University. Daniel Johansson provided access to modern turtle skins in the herpetological collection at the Zoological Museum in Copenhagen, Denmark. Raffael Ernst and Markus Auer provided images of Carettochelys skin from the herpetological collection at the Senckenberg Museum in Dresden, Germany. Lars Skou Olsen provided information on resident testudines housed in the collections at the National Aquarium of Denmark. Financial support was provided by a Grant for Distinguished Young Researchers (642-2014-3773; Swedish Research Council) to J.L.
2023-01-202023-01-202023-06-05Bibliographically approved