{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T03:13:09Z","timestamp":1775704389797,"version":"3.50.1"},"reference-count":41,"publisher":"The Company of Biologists","license":[{"start":{"date-parts":[[2018,1,1]],"date-time":"2018-01-01T00:00:00Z","timestamp":1514764800000},"content-version":"am","delay-in-days":0,"URL":"http:\/\/www.biologists.com\/user-licence-1-1\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1262124"],"award-info":[{"award-number":["1262124"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006445","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1004057"],"award-info":[{"award-number":["1004057"]}],"id":[{"id":"10.13039\/100006445","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Crocodilians have played a significant role in evolutionary studies of archosaurs. Given that several major shifts in forelimb function occur within Archosauria, forelimb morphologies of living crocodilians are of particular importance in assessing locomotor evolutionary scenarios. A previous X-ray investigation of walking alligators revealed substantial movement of the shoulder girdle, but since the sternal cartilages do not show up in X-ray, the source of the mobility could not be conclusively determined. Scapulocoracoid movement was interpreted to indicate independent sliding of each coracoid at the sternocoracoid joint; however, rotations of the sternum could also produce similar displacement of the scapulocoracoids. Here, we present new data employing marker-based XROMM (X-ray Reconstruction of Moving Morphology), wherein simultaneous biplanar X-ray video and surgically implanted radio-opaque markers permit precise measurement of the vertebral axis, sternum, and coracoid in walking alligators. We found that movements of the sternum and sternocoracoid joint both contribute to shoulder girdle mobility and stride length, and that the sternocoracoid contribution was less than previously estimated. On average, the joint contributions to stride length (measured with reference to a point on the distal radius, thus excluding wrist motion) are as follows: thoracic vertebral rotation 6.2\u00b13.7%, sternal rotation 11.1\u00b12.5%, sternocoracoid joint 10.1\u00b15.2%, glenohumeral joint 40.1\u00b17.8%, and elbow 31.1\u00b14.2%. To our knowledge this is the first evidence of sternal movement relative to the vertebral column (presumably via rib joints) contributing to stride length in tetrapods.<\/jats:p>","DOI":"10.1242\/jeb.186791","type":"journal-article","created":{"date-parts":[[2018,9,28]],"date-time":"2018-09-28T08:39:27Z","timestamp":1538123967000},"source":"Crossref","is-referenced-by-count":11,"title":["Alligator (<i>Alligator mississippiensis<\/i>) sternal and shoulder girdle mobility increase stride length during high walks"],"prefix":"10.1242","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2139-6609","authenticated-orcid":false,"given":"David B.","family":"Baier","sequence":"first","affiliation":[{"name":"Providence College, Biology, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brigid M.","family":"Garrity","sequence":"additional","affiliation":[{"name":"Boston University, School of Graduate Medical Science and School of Public Health, Boston, MA 02215, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sabine","family":"Moritz","sequence":"additional","affiliation":[{"name":"Brown University, Ecology and Evolutionary Biology, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ryan M.","family":"Carney","sequence":"additional","affiliation":[{"name":"University of South Florida, Department of Integrative Biology, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"237","published-online":{"date-parts":[[2018,1,1]]},"reference":[{"key":"2021042513352645300_JEB186791C1","doi-asserted-by":"publisher","first-page":"569","DOI":"10.1111\/joa.12245","article-title":"Comparative architectural properties of limb muscles in Crocodylidae and Alligatoridae and their relevance to divergent use of asymmetrical gaits in extant Crocodylia","volume":"225","author":"Allen","year":"2014","journal-title":"J. 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