| Summary: | The anatomy of large cetaceans, such as Balaenopterid whales, is extremely difficult to understand. This is due to physical constraints, limited time for field dissection, and rarity of specimens. In particular, the laryngeal structure and position is extremely hard to understand three dimensionally, as they exhibit a complexly integrated morphology involving bone, muscle, cartilage, and soft tissue air sacs. In previous studies, the muscular anatomy and associated position and movements of the larynx have only been schematically diagrammed. Our study reconstructs the surrounding spaces, positions, and ranges of laryngeal movement by applying muscle volumes and vectors of trajectories between points on a reconstructed 3‐D model of skull, hyoid, and laryngeal cartilages. This gives us a better understanding of how these whales may position and use the laryngeal apparatus in a variety of functions (vocalization, bubble making, etc.). Laryngeal structure and position were reconstructed using a variety of approaches, including dissections of one infant minke whale ( Balaenoptera acutorostrata ) head, and two adult larynges of a fin whale ( Balaenoptera physalus ) and a humpback whale ( Balaenoptera physalus ). CT and MR imaging were obtained on all three specimens. Additional osteological data was obtained from an infant minke whale skull and one publicly available humpback whale skeleton. Photogrammetry and CT reconstruction software were used to create 3‐D digital reconstructions of the skulls. Photogrammetry was also used to document shape, articulations, and positions of cartilage structures during dissection. These data culminate in the construction of an animated 3‐D model that elucidates the hard and soft tissue anatomy, relative positions of structures and spaces, and movements of the laryngeal apparatus of a generic Balaenopterid whale. Using this model, we can elucidate both intrinsic and extrinsic movements of the larynx. Our results indicate that intrinsic cartilage movement is restricted primarily to ...
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