Quantitative computed tomography of humpback whale (Megaptera novaeangliae) mandibles : mechanical implications for rorqual lunge-feeding
Field, Daniel J.
Goldbogen, Jeremy A.
Shadwick, Robert E.
MetadataShow full item record
Rorqual whales (Balaenopteridae) lunge at high speed with mouth open to nearly 90 degrees in order to engulf large volumes of prey-laden water. This feeding process is enabled by extremely large skulls and mandibles that increase mouth area, thereby facilitating the flux of water into the mouth. When these mandibles are lowered during lunge-feeding, they are exposed to high drag and therefore may be subject to significant bending forces. We hypothesized that these mandibles exhibited a mechanical design (shape and density distribution) that enables these bones to accommodate high loads during lunge-feeding without exceeding their breaking strength. We used quantitative computed tomography (QCT) to determine the three-dimensional geometry and density distribution of a pair of sub-adult humpback whale (Megaptera novaeangliae) mandibles (length = 2.10 m). QCT data indicated highest bone density and crosssectional area, and therefore high resistance to bending and deflection, from the coronoid process to the middle of the dentary, which then decreased towards the anterior end of the mandible. These results differ from the caudorostral trends of increasing mandibular bone density in mammals such as humans and the right whale, Eubalaena glacialis, indicating that adaptive bone remodeling is a significant contributing factor in establishing mandibular bone density distributions in rorquals.
Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology 293 (2010): 1240-1247, doi:10.1002/ar.21165
Showing items related by title, author, creator and subject.
The use of diagnostic imaging for identifying abnormal gas accumulations in cetaceans and pinnipeds Dennison, Sophie; Fahlman, Andreas; Moore, Michael J. (Frontiers Media, 2012-06-06)Recent dogma suggested that marine mammals are not at risk of decompression sickness due to a number of evolutionary adaptations. Several proposed adaptations exist. Lung compression and alveolar collapse that terminate ...
Bentov, Shmuel; Aflalo, Eliahu D.; Tynyakov, Jenny; Sagi, Amir; Glazer, Lilah (Nature Publishing Group, 2016-02-24)Crustaceans, like most mineralized invertebrates, adopted calcium carbonate mineralization for bulk skeleton reinforcement. Here, we show that a major part of the crustacean class Malacostraca (which includes lobsters, ...
Tsukrov, Igor; DeCew, Judson C.; Baldwin, Kenneth C.; Campbell-Malone, Regina; Moore, Michael J. (2009-03-11)In an effort to better understand the mechanics of ship-whale collision and to reduce the associated mortality of the critically endangered North Atlantic right whale, a comprehensive biomechanical study has been conducted ...