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A Quick Trip To The Deep

25 Sep

Browsing around online I happened to find this interesting article over at the Nature site based on a study of the observed osteological changes and the long-term effects of deep-sea diving on a selection of sperm whale (Physeter macrocephalus) skeletal remains.   The article, by Moore and Early (2004), highlights the value of conducting osteological work on animal remains, especially in consideration of furthering the knowledge of oceanic mammals and how their bodies react to their deep water lifestyle.  The study examined 16 partial or complete modern sperm whale carcasses from both the Pacific and Atlantic oceans, with the results finding the effects of osteonecrosis affecting the chevron and rib articular surfaces and nasal bones, which increased in severity with age of the individuals studied in the sample (Moore & Early 2004: 2215).

Osteonecrosis itself is a recognised chronic pathology in humans, albeit one with numerous aetiologies which can include irradiation, dysbaric stress, thermal injuries, and hemopoietic disorders among others, but Moore & Early (2004: 2215) highlight the fact that “nitrogen emboli induced the observed (dysbaric) osteonecrosis” in the studied sperm whale skeletons.  This indicates that the whales suffered the progressive cumulative effects of the bends during disturbed dives which led to the destructive bone changes during the course of the whales life.  Importantly this study indicates that it “appears that sperm whales may be neither anatomically nor physiologically immune to the effects of deep diving” (Moore & Early 2004: 2215), insofar as much as previously thought.

Bibliography

Hopkin, M. 2004. Sperm Whales Suffer the Bends. Nature. Online Article. doi:10.1038/news041220-13.

Moore, M. J. & Early, G. A. 2004. Cumulative Sperm Whale Bone Damage and the Bends. Science. 306 (5705): 2215.