Having a big nose: structure, ontogeny, and function of the elephant seal proboscis

摘要: The proboscis of male elephant seals (Mirounga Gray, 1827) has been suggested as an example a secondary sexual trait since Darwin. There much speculation about its social function (e.g., optical signal breeding status, amplification vocalizations, cue for female choice). However, it never studied in detail, probably because fleshy nature makes measurement difficult. In this paper, we employ photogrammetry to measure the and facial morphology large sample wild, unrestrained, displaying southern leonina (L., 1758)). We describe ontogeny allometry analyze current phenotypic selection pressures on traits. discuss potential role acoustic signaling resource-holding status. demonstrate that size is positively correlated with age body independently, currently under positive pressure whe...