{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T16:00:25Z","timestamp":1792080025996,"version":"4.4.0"},"reference-count":49,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2019,5,8]],"date-time":"2019-05-08T00:00:00Z","timestamp":1557273600000},"content-version":"vor","delay-in-days":1,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/501100000923","name":"Australian Research Council","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100000923","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Future Fellowship","award":["FT130101965"],"award-info":[{"award-number":["FT130101965"]}]},{"name":"University of Adelaide Research Fellowship"},{"name":"ARC Discovery Project","award":["DP160103005"],"award-info":[{"award-number":["DP160103005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2019,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Morphological variation among the viviparous sea snakes (Hydrophiinae), a clade of fully aquatic elapid snakes, includes an extreme \u201cmicrocephalic\u201d ecomorph that has a very small head atop a narrow forebody, while the hind body is much thicker (up to three times the forebody girth). Previous research has demonstrated that this morphology has evolved at least nine times as a consequence of dietary specialization on burrowing eels, and has also examined morphological changes to the vertebral column underlying this body shape. The question addressed in this study is what happens to the skull during this extreme evolutionary change? Here we use X-ray micro-computed tomography and geometric morphometric methods to characterize cranial shape variation in 30 species of sea snakes. We investigate ontogenetic and evolutionary patterns of cranial shape diversity to understand whether cranial shape is predicted by dietary specialization, and examine whether cranial shape of microcephalic species may be a result of heterochronic processes. We show that the diminutive cranial size of microcephalic species has a convergent shape that is correlated with trophic specialization to burrowing prey. Furthermore, their cranial shape is predictable for their size and very similar to that of juvenile individuals of closely related but non-microcephalic sea snakes. Our findings suggest that heterochronic changes (resulting in pedomorphosis) have driven cranial shape convergence in response to dietary specializations in sea snakes.<\/jats:p>","DOI":"10.1093\/icb\/icz033","type":"journal-article","created":{"date-parts":[[2019,4,25]],"date-time":"2019-04-25T07:13:51Z","timestamp":1556176431000},"page":"616-624","source":"Crossref","is-referenced-by-count":34,"title":["Heterochronic Shifts Mediate Ecomorphological Convergence in Skull Shape of Microcephalic Sea Snakes"],"prefix":"10.1093","volume":"59","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2164-7877","authenticated-orcid":false,"given":"Emma","family":"Sherratt","sequence":"first","affiliation":[{"name":"South Australian Museum, North Terrace, Adelaide, South Australia 5000, Australia"},{"name":"School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kate L","family":"Sanders","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amy","family":"Watson","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark N","family":"Hutchinson","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia"},{"name":"South Australian Museum, North Terrace, Adelaide, South Australia 5000, Australia"},{"name":"College of Science and Engineering, Flinders University, Adelaide, South Australia 5042, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael S Y","family":"Lee","sequence":"additional","affiliation":[{"name":"South Australian Museum, North Terrace, Adelaide, South Australia 5000, Australia"},{"name":"College of Science and Engineering, Flinders University, Adelaide, South Australia 5042, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Palci","sequence":"additional","affiliation":[{"name":"South Australian Museum, North Terrace, Adelaide, South Australia 5000, Australia"},{"name":"College of Science and Engineering, Flinders University, Adelaide, South Australia 5042, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2019,5,7]]},"reference":[{"key":"2019092012012553400_icz033-B1","doi-asserted-by":"crossref","first-page":"2675","DOI":"10.1111\/evo.12463","article-title":"A method for assessing phylogenetic least squares models for shape and other high-dimensional multivariate 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