{
    "abstract": "During swallowing, a diverse range of mammals - from opossums to humans - propel food boluses out of the oropharynx via tongue base retraction (TBR). The widespread distribution of TBR behavior implies an ancient evolutionary origin, but the biomechanical mechanisms of TBR remain poorly understood. The evolution of TBR behavior is further complicated by the diversity of hyoid and tongue anatomy across mammals: to what extent does hyolingual morphology shape TBR mechanism? Using biplanar videoradiography and the XROMM workflow, we collected high-resolution 3D kinematic data in opossums (Marsupialia), dogs (Placentalia), and macaques (Placentalia) to test hypotheses on the evolutionary conservation of TBR mechanisms. Despite differences in hyolingual morphology and resting hyoid position, both dogs and macaques drive TBR through hyoid movement: hyoid excursions reduce the oral volume and squeeze the tongue base posteriorly, analogous to a hydraulic pump displacing an incompressible fluid. In opossums however, intrinsic lingual muscles deform the tongue base to initiate TBR, independent of hyoid movement and oral volume change. We suggest that multiple mechanisms are viable for the highly conserved TBR behavior across mammals, and the functional diversity of TBR mechanisms is decoupled from the morphological diversity of the hyolingual system. This decoupling may have facilitated the evolution of novel hyolingual phenotypes while avoiding trade-offs in swallowing performance.",
    "authors": [
        {
            "affiliation": "Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio, USA.",
            "firstname": "Peishu",
            "initials": "P",
            "lastname": "Li"
        },
        {
            "affiliation": "Department of Organismal Biology and Anatomy, University of Chicago, Chicago IL, USA.",
            "firstname": "Kaleb C",
            "initials": "KC",
            "lastname": "Sellers"
        },
        {
            "affiliation": "Department of Radiology, University of Vermont Medical Center, Burlington VT, USA.",
            "firstname": "Courtney P",
            "initials": "CP",
            "lastname": "Orsbon"
        },
        {
            "affiliation": "National Renewable Energy Laboratory, Golden CO, USA.",
            "firstname": "J D",
            "initials": "JD",
            "lastname": "Laurence-Chasen"
        },
        {
            "affiliation": "Illinois Mathematics and Science Academy, Aurora IL, USA.",
            "firstname": "Riya",
            "initials": "R",
            "lastname": "Gumidyala"
        },
        {
            "affiliation": "The College, University of Chicago, Chicago IL, USA.",
            "firstname": "Madison",
            "initials": "M",
            "lastname": "Yuan"
        },
        {
            "affiliation": "The College, University of Chicago, Chicago IL, USA.",
            "firstname": "George",
            "initials": "G",
            "lastname": "Huerta"
        },
        {
            "affiliation": "Department of Otolaryngology-Head and Neck Surgery, University of Missouri School of Medicine, Columbia MO, USA.",
            "firstname": "Teresa E",
            "initials": "TE",
            "lastname": "Lever"
        },
        {
            "affiliation": "Department of Biology, Knox College, Galesburg IL, USA.",
            "firstname": "Nicholas J",
            "initials": "NJ",
            "lastname": "Gidmark"
        },
        {
            "affiliation": "Department of Organismal Biology and Anatomy, University of Chicago, Chicago IL, USA.",
            "firstname": "Zhe-Xi",
            "initials": "ZX",
            "lastname": "Luo"
        },
        {
            "affiliation": "Department of Organismal Biology and Anatomy, University of Chicago, Chicago IL, USA.",
            "firstname": "Callum F",
            "initials": "CF",
            "lastname": "Ross"
        }
    ],
    "conclusions": null,
    "copyrights": "\u00a9 The Author(s) 2025. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.",
    "doi": "10.1093/icb/icaf016",
    "journal": "Integrative and comparative biology",
    "keywords": [],
    "methods": null,
    "publication_date": "2025-04-17",
    "pubmed_id": "40240300",
    "results": null,
    "title": "Diverse Tongue Base Retraction Strategies Drive Bolus Propulsion during Mammalian Swallowing.",
    "xml": "<Element 'PubmedArticle' at 0x788506661210>"
}