1984/08/01 by John E. Heyning · 2 citations
Earth and Planetary Sciences · Environmental Science · #Arctic and Antarctic ice dynamics #Marine and coastal plant biology #Marine animal studies overview
paper · doi:10.1139/z84-239
openalex publication_date 1984/08/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Numerous authors have attributed the linear scars on male beaked whales to intraspecific fighting. The species Mesoplodon carlhubbsi was examined from a structural viewpoint to describe functionally how such scarring may result. In this species, linear scars occur in two patterns: single scars and parallel scars. Parallel scars occur when both of the large teeth possessed by the aggressor male come in contact simultaneously with the inflicted whale. In mature males, the teeth project from the lower jaw outside the mouth up along both sides of the rostrum to a height greater than the top of the rostrum. This indicates that the teeth are used with the mouth closed by bringing the dorsal aspect of the rostrum in contact with the soon to be inflicted whale. The densely ossified mesorostral canal evident in mature males probably functions in reinforcing the rostrum as the males engage in fighting. Two evolutionary trends in Mesoplodon dentition are hypothesized: (i) the change in position of the teeth in the mandibles from an apical (primitive) position back to a more posterior position; (ii) once situated farther back on the mandibles, to raise the apex of the teeth above the level of the rostrum. Comments on other Mesoplodon species are noted for comparisons.