Oceanography Paper
BONE-EATING WORMS FROM THE ANTARCTIC: the contrasting fate of whale and wood remains on the Southern Ocean Seafloor
OLUDAMILOLA ADESIYUN
GEOL 440
DR. CARL RICHTER
NOVEMBER 17, 2013
This paper explains the results from the first experimental study of the fate of whale and wood remains on the Antarctic seafloor. Using a baited free-vehicle lander design, it is observed that whale-falls in the Antarctic are heavily infested by at least two new species of bone-eating worm, Osedax antarcticus sp. and Osedax deceptionensis sp. In stark contrast, wood remains are remarkably well preserved with the absence of typical wood-eating fauna such as the xylophagainid bivalves. The combined whale-fall and wood fall experiment provides support to the hypothesis that the Antarctic circumpolar current is a barrier to the larvae of deep-water species that are broadly distributed in other ocean basins. Since humans first started exploring the Antarctic, wood has been deposited on the seafloor in the form of shipwrecks and waste; the data shown in this experiment suggests that this anthropogenic wood may be exceptionally well preserved. Alongside the new species descriptions, a comprehensive phylogenetic analyses of Osedax was conducted, suggesting the clade is most closely related to the frenulate tubeworms, not the vestimentiferans as previous reported (Glover, 2013).
Studies in other ocean basins have suggested that the final resting place of wood and whale remains is often the continental shelf or slope, where they form ephemeral organic-rich ‘island’ habitats for deep-sea fauna to feed from, termed ‘wood falls’ and ‘whale-falls’. These studies have shown that wood and whale bone are colonized by a remarkable range of specialist deep sea organisms, the majority of them new to science. Two of the most important in the deep sea are the Xylophagainae bivalves, which bore into wood, and the Osedax ‘bone-eating’ worms, members of the annelid clade that bore into
OLUDAMILOLA ADESIYUN
GEOL 440
DR. CARL RICHTER
NOVEMBER 17, 2013
This paper explains the results from the first experimental study of the fate of whale and wood remains on the Antarctic seafloor. Using a baited free-vehicle lander design, it is observed that whale-falls in the Antarctic are heavily infested by at least two new species of bone-eating worm, Osedax antarcticus sp. and Osedax deceptionensis sp. In stark contrast, wood remains are remarkably well preserved with the absence of typical wood-eating fauna such as the xylophagainid bivalves. The combined whale-fall and wood fall experiment provides support to the hypothesis that the Antarctic circumpolar current is a barrier to the larvae of deep-water species that are broadly distributed in other ocean basins. Since humans first started exploring the Antarctic, wood has been deposited on the seafloor in the form of shipwrecks and waste; the data shown in this experiment suggests that this anthropogenic wood may be exceptionally well preserved. Alongside the new species descriptions, a comprehensive phylogenetic analyses of Osedax was conducted, suggesting the clade is most closely related to the frenulate tubeworms, not the vestimentiferans as previous reported (Glover, 2013).
Studies in other ocean basins have suggested that the final resting place of wood and whale remains is often the continental shelf or slope, where they form ephemeral organic-rich ‘island’ habitats for deep-sea fauna to feed from, termed ‘wood falls’ and ‘whale-falls’. These studies have shown that wood and whale bone are colonized by a remarkable range of specialist deep sea organisms, the majority of them new to science. Two of the most important in the deep sea are the Xylophagainae bivalves, which bore into wood, and the Osedax ‘bone-eating’ worms, members of the annelid clade that bore into
References: Glover AG, Wiklund H, Taboada S, Avila C, Cristobo J, Smith CR, Kemp KM, Jamieson AJ, Dahlgren TG. 2013 Bone-eating worms from the Antarctic: the contrasting fate of whale and wood remains on the Southern Ocean seafloor. Proc R Soc B 280: 20131390. http://dx.doi.org/10.1098/rspb.2013.1390 Sellius G. 1733 Historia Naturalis Teredinis seuXylophagi Marini, tubulo-conchoidis speciatim Belgici. Apud Hermannum Besseling: Trajecti adRhenum. Turner RD. 1973 Wood-boring bivalves, opportunistic species in the deep sea. Science 180, 1377–1379. (doi:10.1126/science.180.4093.1377 Smith CR, Kukert H, Wheatcroft RA, Jumars PA, Deming JW. 1989 Vent fauna on whale remains. Nature 341, 27–28. (doi:10.1038/341027a0) Smith CR. 2006 Bigger is better: the role of whales as detritus in marine ecosystems. In Whales, whaling and ocean ecosystems (eds JA Estes,DP DeMaster, DF Doak, TM Williams, RL Brownell), pp. 286–302. Berkeley, CA: University of California Press.