Sensory anatomy of the most aquatic of carnivorans: the Antarctic Ross seal, and convergences with other mammals

• Published in: Biology Letters
• Main Authors: Loza, Cleopatra Mara, Latimer, Ashley E., Sánchez-Villagra, Marcelo R., Carlini, Alfredo A.
• Other Authors: Universidad de La Plata, Argentina
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Royal Society 2017
• Subjects: Antarctic; The Antarctic; Antarc*; Ross Seal
• Online Access: http://dx.doi.org/10.1098/rsbl.2017.0489; https://royalsocietypublishing.org/doi/pdf/10.1098/rsbl.2017.0489; https://royalsocietypublishing.org/doi/full-xml/10.1098/rsbl.2017.0489

Transitions to and from aquatic life involve transformations in sensory systems. The Ross seal, Ommatophoca rossii , offers the chance to investigate the cranio-sensory anatomy in the most aquatic of all seals. The use of non-invasive computed tomography on specimens of this rare animal reveals, relative to other species of phocids, a reduction in the diameters of the semicircular canals and the parafloccular volume. These features are independent of size effects. These transformations parallel those recorded in cetaceans, but these do not extend to other morphological features such as the reduction in eye muscles and the length of the neck, emphasizing the independence of some traits in convergent evolution to aquatic life.