Smith, M. M. & Sansom, I. J. in Development, Function and Evolution of Teeth (eds Teaford M.F. et al.) Ch. 5 (Cambridge Univ. Press, 2000).
Gans, C. & Northcutt, R. G. Neural crest and the origin of vertebrates: a new head. Science 220, 268–273 (1983).
Smith, M. P., Sansom, I. J. & Repetski, J. E. Histology of the first fish. Nature 380, 702–704 (1996).
Bockelie, T. & Fortey, R. A. An early Ordovician vertebrate. Nature 260, 36–38 (1976).
Repetski, J. E. A fish from the Upper Cambrian of North America. Science 200, 529–531 (1978).
Paul Smith, M. & Sansom, I. J. The affinity of Anatolepis Bockelie & Fortey. Geobios 28, 61–63 (1995).
Peel, J. S. & Higgins, A. K. Anatolepis – a problematic Ordovician vertebrate reinterpreted as an arthropod. Rapp. Grønl. Geol. Unders. 85, 108–109 (1977).
Peel, J. S. Anatolepis from the Early Ordovician of East Greenland – not a fishy tail. Rapp. Grønl. Geol. Unders. 91, 111–115 (1979).
Naimark, E.B. & Chaika, S.Y. The complex structure of the cuticle of Pseudagnostus (Agnostina, Trilobita?). Paleontol. J. 57, 762–774 (2023).
Keil, T. A. Comparative morphogenesis of sensilla: a review. Int. J. Insect Morphol. Embryol. 26, 151–160 (1997).
Bryant, W. L. A study of the oldest known vertebrates, Astraspis and Eriptychius. Proc. Am. Philos. Soc. 76, 409–427 (1936).
Sansom, I. J., Smith, M. P., Smith, M. M. & Turner, P. The Harding Sandstone revisited -a new look at some old bones. Geobios 28, 57–59 (1995).
Dearden, R. P. et al. The oldest three-dimensionally preserved vertebrate neurocranium. Nature https://doi.org/10.1038/s41586-023-06538-y (2023).
Pashley, D. H. Mechanisms of dentin sensitivity. Dent. Clin. North Am. 34, 449–473 (1990).
Byers, M. R. in International Review of Neurobiology Vol. 25 (eds Smythies, J. R. & Bradley, R. J.) 39–94 (Elsevier, 1984).
Magloire, H., Couble, M.-L., Thivichon-Prince, B., Maurin, J.-C. & Bleicher, F. Odontoblast: a mechano-sensory cell. J. Exp. Zool. B 312B, 416–424 (2009).
Murdock, D. J. E. et al. The origin of conodonts and of vertebrate mineralized skeletons. Nature 502, 546–549 (2013).
Donoghue, P. C. J. & Rücklin, M. The ins and outs of the evolutionary origin of teeth. Evol. Dev. 18, 19–30 (2016).
Fraser, G. J., Cerny, R., Soukup, V., Bronner-Fraser, M. & Streelman, J. T. The odontode explosion: the origin of tooth-like structures in vertebrates. BioEssays 32, 808–817 (2010).
Donoghue, P. Evolution: divining the nature of the ancestral vertebrate. Curr. Biol. 27, R277–R279 (2017).
Huysseune, A., Sire, J.-Y. & Witten, P. E. Evolutionary and developmental origins of the vertebrate dentition. J. Anat. 214, 465–476 (2009).
Donoghue, P. C. J. & Sansom, I. J. Origin and early evolution of vertebrate skeletonization. Microsc. Res. Tech. 59, 352–372 (2002).
Rücklin, M. & Donoghue, P.C. in eLS, https://doi.org/10.1002/9780470015902.a0026408 (John Wiley & Sons, 2025).
Ahlberg, P.E. (ed.) Major Events in Early Vertebrate Evolution, 1st edn (CRC Press, 2001).
Reif, W.-E. in Evolutionary Biology (eds Hecht, M. K. et al.) 287–368 (Springer, 1982).
Debiais-Thibaud, M. et al. The homology of odontodes in gnathostomes: insights from Dlx gene expression in the dogfish, Scyliorhinus canicula. BMC Evol. Biol. 11, 307 (2011).
Haridy, Y., Gee, B. M., Witzmann, F., Bevitt, J. J. & Reisz, R. R. Retention of fish-like odontode overgrowth in Permian tetrapod dentition supports outside-in theory of tooth origins. Biol. Lett. 15, 20190514 (2019).
Smith, M. M. Putative skeletal neural crest cells in early Late Ordovician vertebrates from Colorado. Science 251, 301–303 (1991).
Stundl, J. et al. Ancient vertebrate dermal armor evolved from trunk neural crest. Proc. Natl Acad. Sci. USA 120, e2221120120 (2023).
Couve, E., Osorio, R. & Schmachtenberg, O. The amazing odontoblast: activity, autophagy, and aging. J. Dent. Res. 92, 765–772 (2013).
Sansom, I. J., Smith, M. P., Armstrong, H. A. & Smith, M. M. Presence of the earliest vertebrate hard tissue in conodonts. Science 256, 1308–1311 (1992).
Blieck, A. et al. Fossils, histology, and phylogeny: why conodonts are not vertebrates. Epidodes 33, 234–241 (2010).
Miyashita, T. et al. Hagfish from the Cretaceous Tethys Sea and a reconciliation of the morphological–molecular conflict in early vertebrate phylogeny. Proc. Natl Acad. Sci. USA 116, 2146–2151 (2019).
Turner, S. et al. False teeth: conodont-vertebrate phylogenetic relationships revisited. Geodiversitas 32, 545–594 (2010).
Qu, Q., Haitina, T., Zhu, M. & Ahlberg, P. New genomic and fossil data illuminate the origin of enamel. Nature 526, 108–111 (2015).
Sire, J.-Y., Davit-Béal, T., Delgado, S. & Gu, X. The origin and evolution of enamel mineralization genes. Cells Tissues Organs 186, 25–48 (2007).
Lebedev, O. A., Mark-Kurik, E., Karatajūtė-Talimaa, V. N., Lukševičs, E. & Ivanov, A. Bite marks as evidence of predation in early vertebrates. Acta Zool. 90, 344–356 (2009).
Halstead, L. B. Vertebrate Hard Tissues (Wykeham, 1974).
Wainwright, S. A., Vosburgh, F. & Hebrank, J. H. Shark skin: function in locomotion. Science 202, 747–749 (1978).
Haridy, Y. et al. Bone metabolism and evolutionary origin of osteocytes: novel application of FIB-SEM tomography. Sci. Adv. 7, eabb9113 (2021).
Hesselbo, S. P. Aglaspidida (Arthropoda) from the Upper Cambrian of Wisconsin. J. Paleontol. 66, 885–923 (1992).
Briggs, D. E. G. & Fortey, R. A. The cuticle of the aglaspidid arthropods, a red-herring in the early history of the vertebrates. Lethaia 15, 25–29 (1982).
Lerosey-Aubril, R., Ortega-Hernández, J., Kier, C. & Bonino, E. Occurrence of the Ordovician-type aglaspidid Tremaglaspis in the Cambrian Weeks Formation (Utah, USA). Geol. Mag. 150, 945–951 (2013).
Sansom, I. J., Smith, M. P., Smith, M. M. & Turner, P. Astraspis-the anatomy and histology of an Ordovician fish. Palaeontology 40, 625–643 (1997).
Denison, R. H. Ordovician Vertebrates from Western United States (Field Museum of Natural History, 1967).
Sansom, I. J., Smith, M. M. & Smith, M. P. Scales of thelodont and shark-like fishes from the Ordovician of Colorado. Nature 379, 628–630 (1996).
Johanson, Z., Tanaka, M., Harriman, N. & Meredith Smith, M. Early Palaeozoic dentine and patterned scales in the embryonic catshark tail. Biol. Lett. 4, 87–90 (2007).
Fried, K. & Gibbs, J. in The Dental Pulp: Biology, Pathology, and Regenerative Therapies (ed. Goldberg, S.) 75–95 (Springer, 2014).
Kollar, E. J. & Lumsden, A. G. Tooth morphogenesis: the role of the innervation during induction and pattern formation. J. Biol. Buccale 7, 49–60 (1979).
Lumsden, A. G. S. & Buchanan, J. A. G. An experimental study of timing and topography of early tooth development in the mouse embryo with an analysis of the role of innervation. Arch. Oral Biol. 31, 301–311 (1986).
Albert, P. J., Zacharuk, R. Y. & Wong, L. Structure, innervation, and distribution of sensilla on the wings of a grasshopper. Can. J. Zool. 54, 1542–1553 (1976).
Locke, M. Pore canals and related structures in insect cuticle. J. Biophys. Biochem. Cytol. 10, 589–618 (1961).
Wigglesworth, V. B. The transfer of lipid in insects from the epidermal cells to the cuticle. Tissue Cell 17, 249–265 (1985).
Young, G. C., Karatajute-Talimaa, V. N. & Smith, M. M. A possible Late Cambrian vertebrate from Australia. Nature 383, 810–812 (1996).
Kim, J. W. & Park, J.-C. Dentin hypersensitivity and emerging concepts for treatments. J. Oral Biosci. 59, 211–217 (2017).
Haspel, G., Schwartz, A., Streets, A., Camacho, D. E. & Soares, D. By the teeth of their skin, cavefish find their way. Curr. Biol. 22, R629–R630 (2012).
Schaefer, S. A. & Buitrago-Suárez, U. A. Odontode morphology and skin surface features of Andean astroblepid catfishes (Siluriformes, Astroblepidae): Odontode morphology. J. Morphol. 254, 139–148 (2002).
Nweeia, M. T. et al. Sensory ability in the narwhal tooth organ system. Anat. Rec. 297, 599–617 (2014).
Catania, K. C. & Remple, M. S. Somatosensory cortex dominated by the representation of teeth in the naked mole-rat brain. Proc. Natl Acad. Sci. USA 99, 5692–5697 (2002).
Weissengruber, G. E., Egerbacher, M. & Forstenpointner, G. Structure and innervation of the tusk pulp in the African elephant (Loxodonta africana). J. Anat. 206, 387–393 (2005).
Miller, J., Loch, J. & Taylor, J. Biostratigraphy of Cambrian and Lower Ordovician strata in the Llano uplift, central Texas. Ch. 4. AAPG Mem. 98, 187–202 (2012).
Fortey, R., Landing, E. & Skevington, D. Cambrian-Ordovician boundary sections in the Cow Head Group, western Newfoundland. Natl Mus. Wales Geol. Ser. 3, 95–129 (1982).
Raasch, G. O. Cambrian Merostomata (Geological Society of America, 1939).
Houée, G., Bardin, J., Germain, D., Janvier, P. & Goudemand, N. Developmental models shed light on the earliest dental tissues, using Astraspis as an example. Palaeontology 66, e12682 (2023).
Smith, M. M. & Sansom, I. J. in Development, Function and Evolution of Teeth (eds. Teaford, M. F. et al.) 65–81 (Cambridge Univ. Press, 2000).
Mori, S. & Nakamura, T. Redeployment of odontode gene regulatory network underlies dermal denticle formation and evolution in suckermouth armored catfish. Sci. Rep. 12, 6172 (2022).
Rivers, M. GSECARS Tomography Software — IDL Tomography Processing. Github https://cars-uchicago.github.io/IDL_Tomography/ (2023).
Onimaru, K., Motone, F., Kiyatake, I., Nishida, K. & Kuraku, S. A staging table for the embryonic development of the brownbanded bamboo shark (Chiloscyllium punctatum). Dev. Dyn. 247, 712–723 (2018).
Gillis, J. A. et al. Big insight from the little skate: Leucoraja erinacea as a developmental model system. Curr. Top. Dev. Biol. 147, 595–630 (2022).
Susaki, E. A. et al. Versatile whole-organ/body staining and imaging based on electrolyte-gel properties of biological tissues. Nat. Commun. 11, 1982 (2020).
Chung, K. et al. Structural and molecular interrogation of intact biological systems. Nature 497, 332–337 (2013).
Smith-Paredes, D. et al. Embryonic muscle splitting patterns reveal homologies of amniote forelimb muscles. Nat. Ecol. Evol. 6, 604–613 (2022).
Griffin, C. T. et al. The developing bird pelvis passes through ancestral dinosaurian conditions. Nature 608, 346–352 (2022).
Schindelin, J. et al. Fiji: an open-source platform for biological-image analysis. Nat. Methods 9, 676–682 (2012).