ANDEEP ANtarctic benthic DEEP sea biodiversity: colonization history and recent community patterns - an international project to investigate the deep-water biology of the Scotia and Weddell seas from F/S Polarstern

Summary

Shallow marine benthic Southern Ocean communities display high levels of endemism, gigantism, slow growth, longevity and late maturity, and adaptive radiations have generated considerable novel biodiversity in some taxa. The deeper parts of the Southern Ocean exhibit some unique environmental features, including a very deep continental shelf and a weakly stratified water column, and are the source for much of the deep water in the World Ocean. These features suggest that deep-sea faunas around the Antarctic may be related both to adjacent shelf communities and to those in other oceans. Unlike shallow-water Antarctic benthic communities, however, little has been known about life in this vast deep-sea region.

Three recent ANDEEP expeditions collected organisms and environmental data at 40 stations between 748-6348 m water depth, increasing known biodiversity substantially and discovering many new species. Evidence is emerging that Southern Ocean deep-water faunas are linked to both adjacent shelf and other ocean basin assemblages. This linkage is complex and varies between taxa. Even though we are only beginning to understand the patterns and scale of Southern Ocean biodiversity, we now would like to understand some forces that drive biodiversity and biogeographic patterns. We would like to understand the function of biodiversity, the role of rare and abundant species. ANDEEP-SYSTCO (ANtarctic benthic DEEP-sea biodiversity: colonisation history and recent community patterns – SYSTem COupling) is an ambitious IPY core project and designed to study processes in different realms of the biosphere in Antarctica and uncover how these systems are linked to each other (atmospheric-pelagic-benthic coupling processes). SYSTCO will help to close another gap in our knowledge of the Southern Ocean deep sea, i.e. the functioning of these communities.

Background of ANDEEP

Prior to ANDEEP the deeper waters of the Scotia and Weddell seas were some of the least explored parts of the world’s oceans and we knew almost nothing about the bottom-dwelling (benthic) animals that inhabit them. By contrast, we know that the present-day benthic shallow shelf animals of the Antarctic continental shelf exhibit many striking and unusual features, including gigantism, longevity, an extraordinarily high degree of endemism, and absence of taxa which are abundant in similar environments elsewhere. Such attributes are believed to reflect the geographical and hydrographical isolation of the shelves and their special environmental characteristics, particularly the persistently cold climate combined with high and markedly seasonal primary production. Periodic extensions of the ice sheet may have enhanced speciation processes on the continental shelf - the Antarctic „diversity pump“. Waters deeper than 1000 m, however, have broad connections with the Pacific, South Atlantic and Indian oceans and were therefore expected to be much less isolated. We therefore wondered whether the faunas of the bathyal and abyssal areas around Antarctica would be similar to those of comparable depths elsewhere.

We also considered the possibility that the deep bottom water production in the Weddell Sea acts as a distribution mechanism, driving Antarctic deep-water faunas northwards into the Atlantic Ocean over evolutionary time-scales. Thus we thought that the Weddell Sea may be an important source for taxa presently living in the Atlantic and other neighbouring parts of the deep oceans. Furthermore, the more-or-less isothermal water column of the Weddell Sea and the surroundings of the Antarctic continent provides an obvious conduit for the migration of shallow-water species into the deeper waters.

The Scotia-Weddell sea region has a long and complicated plate tectonic history, which has provided a rich and changing variety of habitats and environmental conditions for marine life over geological time. Whereas the formation of the Weddell Sea began during Jurassic time (165 million years ago), a continental link between South America and Antarctica persisted until a little more than 20 million years ago. The disruption of this link and the dispersal of its continental fragments allowed the inception of the Circum-Polar Current and caused the geographical and climatic isolation of Antarctica. These geographical and climatic changes, including intermittent periods of global warming and global sea-level rise and fall, are likely to have influenced migration in and out of the Antarctic region.

The continental remnants of the old land link now form many of the islands within the Scotia arc, whereas others are submarine islands, 1000 m below sea level, and possible refuges for animals exiled from the Antarctic continental shelf by advancing ice sheets. A chain of volcanoes, the South Sandwich Islands, and their associated subduction trench (> 7000 m) to the west represent a highly active tectonic environment that contrasts with the weakly active trench off the South Shetland Islands. To address these issues, different areas of the deep sea, and of submerged continental blocks, which might be faunal refuges, have been selected for investigation.

The ANDEEP project aimed to provide a first base-line survey of the deep-water benthic faunas of the Scotia and Weddell seas, and document the variety of sea-floor habitats present within their submarine geographical settings.

The scientific objectives of ANDEEP were:
- to investigate the evolutionary processes and oceanographic changes which have resulted in the present biodiversity and distributional patterns in the Antarctic deep seas
- to investigate the influence of sea-floor habitat diversity on species and genetic diversity in the Antarctic deep sea
- to investigate the colonisation and exchange processes of the deep sea fauna in relation to changes in sea-bed geography over geological time
- to assess the importance of the Antarctic region as a possible source for many of the deep sea benthic taxa in other oceans.


Foto ANDEEP taken by Bob Diaz, VIMS, USA from a depth of 6348 m, South Sandwich Graben with Ophiuriden and Crinioden (Bathycrinus).


Selected ANDEEP publications: Deep Sea Research - Part II and Nature


Selected important ANDEEP taxa. a, A new species of komokiacean (Ipoa sp. nov.) from the Weddell Sea abyssal plain; b, The carnivorous sponge, Chondrocladia from the Weddell Sea abyssal plain ANDEEP II, station 134); c, Bivalve mollusc, Cuspidaria sp. from the abyssal Weddell Sea and South African basins; d, Bivalve mollusc, Limatula sp. from the Weddell Sea; e, Polychaete, Ophryotrocha from the Weddell Sea; f, Nematode, Molgolaimus sp. from the Weddell Sea; g, Isopod crustacean, Ischnomesus sp from the Weddell Sea; h, Isopod, Munnopsis sp. from the western Weddell Sea.



Pictures of new isopods - top: Ischnomesidae, bottom: Munnopsidae

Scientists

Angelika Brandt
Zoological Museum
University of Hamburg

Stefanie Kaiser
Zoological Museum
University of Hamburg

Wiebke Broekeland
Forschungsinstitut Senckenberg
DZBM, Wilhelmshaven

Research areas

Drake Passage, surrounding deep sea of South Shetland Islands, Bellingshausen Sea, Weddell Sea, Scotia arc, South Sandwich Islands, Cape Basin, Agulhas Basin

Publications

Brandt, A. (2003): Frontoserolis abyssalis sp. nov. and Serolis arntzi sp. nov. from the Antarctic deep sea. Beaufortia 53(3): 111-128.

Fütterer, D. K.; Brandt, A. and G. C. B. Poore (2003): The expeditions Antarktis-XIX/3 and XIX/4 of the Research Vessel POLARSTERN in 2002 (ANDEEP I and II: Antarctic Benthic deep-sea Biodiversity: colonisation history and recent community patterns). Berichte Polarforsch Meeresforsch. 470: 1-174.

Gutt, J.; Arntz, W. E.; Balguerias, E.; Brandt, A.; Gerdes, D.; Gorny, M.; Sirenko, B. (2003): Diverse approaches to the questions of biodiversity: German contributions to studies of marine benthos around South America and Antarctica. Gayana 76(2): 177-189.

Brandt, A. (2004): Abundance, diversity, and community patterns of isopods in the Weddell Sea (Crustacea, Isopoda). (EVOLANTAR), Antarctic Science 16 (1): 5-10.

Malyutina, M. and A. Brandt (2004): New records of Storthyngura (Crustacea, Isopoda, Asellota) from the Antarctic deep sea with descriptions of two new species. Mitt. Mus. Nat.kd. Berl., Zool., Reihe. 80 (1): 3-32.

Choudhury, M. and Brandt, A. (2004): Mesosignum weddellensis sp. nov. (Crustacea: Asellota: Mesosignidae), a new isopod species from the abyssal Weddell Sea, Antarctica. Zootaxa 501: 1-10.

Malyutina, M. and Brandt, A. (2004): Rectisura menziesi sp. nov. - a new deep-sea isopod from the Weddell Sea, Southern Ocean (Storthyngurinae: Munnopsididae: Asellota). Mitt. Hamb. Zool. Mus. Inst. 101: 237-247.

Malyutina, M. and Brandt, A. (2004): Acanthocopinae (Crustacea: Isopoda: Munnopsididae) from the Southern Ocean deep sea with the description of Acanthocope eleganta sp. nov. Zootaxa 550:1-20.

Malyutina, M. and Brandt, A. (2004): An addition to the fauna of Storthyngurinae (Isopoda: Asellota: Munnopsididae) from the Antarctic deep sea with the descriptions of three new species. Beaufortia, 54 (1): 1-38.

Brandt, A.; Brökeland, W.; Brix, S.; Malyutina, M. (2004): Diversity of Antarctic deep-sea Isopoda (Crustacea, Malacostraca) – a comparison with shelf data. Deep-Sea Research II 51 (14-16): 1753-1769.

Brandt, A. C. de Broyer, A. J. Gooday, B. Hilbig and M.R.A. Thomson: Introduction to ANDEEP (ANtarctic benthic DEEP-sea biodiversity: colonization history and recent community patterns: a tribute to Howard L. Sanders (2004): Deep-Sea Research II 51 (14-16): 1457-1467.

Brökeland, W. and Brandt, A. (2004): Neoteny in the deep sea asellote family Ischnomesidae (Crustacea: Isopoda) and descriptions of two new species from the Southern Ocean. Deep-Sea Research II 51 (14-16): 1769-1787.

Brandt, A. (2005): Evolution of Antarctic biodiversity in the context of the past: the importance of the Southern Ocean deep sea. Antarctic Science 17(4): 509-521.

Brandt, A. Ellingsen, K.E.E., Brix, S., Brökeland, W. and M. Malyutina (2005): Southern Ocean deep-sea isopod species richness (Crustacea, Malacostraca): influences of depth, latitude and longitude. Polar Biology 28: 284-289.

Brandt, A. (2005): Isopoda of the European North Atlantic from depths exceeding 2000 m (without Epicaridea). Mitt. Hamb. Zool. Mus. Inst. 102: 179-190.

Kaiser, S., Brix, S. (2005): A new isopod species from the Southern Ocean: Disparella maiuscula sp. nov. (Isopoda: Asellota: Desmosomatidae). Mitt. Hamb. Zool. Mus. Inst., Band 102: pp. 153-165.

Brandt, A. (2006): Marine Biodiversität in den Polarregionen: Nordpolarmeer versus Südpolarmeer. In: J. L. Lozán (ed.) Warnsignale aus den Polarregionen 2006, pp. 164-168.

Brandt, A. (2006): Lebensgemeinschaften der Tiefsee. In: G. Hempel, I. Hempel and S. Schiel (eds.), Ökologisches Lesebuch, H.M. Hauschild Verlag, Bremen, pp. 166-170.

Brix, S. (2006): A new species of Desmosomatidae (Isopoda: Crustacea) from the deep Southern Ocean: Eugerdella serrata sp. nov. including remarks to the morphological variability within Eugerdella Hessler, 1970. Mitteilungen aus dem hamburger zoologischen Museum und Institut. S. 69 – 84.

Brökeland, W. and Brandt, A. (2006): New records of Mastigoniscus Lincoln, 1985 (Isopoda: Asellota: Haplonisscidae) in the Southern Ocean, with descriptions of three new species. Mitt. Ham. zool. Mus. Inst. 103: 85-128.

Choudhury, M. and Brandt, A. (2006) Mesosignum bathyalis sp. nov. (Crustacea, Isopoda, Asellota) from the bathyal Weddell Sea, Antarctica. Mitt. Ham. zool. Mus. Inst. 103: 129-136.

Malyutina, M. and Brandt, A. (2006): A revaluation of the Eurycopinae (Crustacea, Isopoda, Munnopsidae) with a description of Dubinectes gen. nov. from the southern Atlantic deep sea. Zootaxa 1272: 1-44.

Brandt, A. (2007); ANDEEP Programme. Encyclopedia of the Antarctic, vol. 1, ed. Beau Riffenburgh. New York: Routledge, 38-39.

Brandt, A. (2007); Marine Biology: Biodiversity, Marine. Encyclopedia of the Antarctic, vol. 1, ed. Beau Riffenburgh. New York: Routledge, 144-149.

Brandt, A. (2007); Marine Biology: History and Evolution. Encyclopedia of the Antarctic, vol. 2., ed. Beau Riffenburgh. New York: Routledge, 627-630.

Brandt, A. (2007): Three new species of Fissarcturus (Isopoda, Antarcturidae) from the Southern Ocean. Journal of the Linnean Society 149: 263-290.

Brandt, A., De Broyer, C., De Mesel, I., Ellingsen, K.E., Gooday, A., Hilbig, B., Linse, K., Thomson, M., Tyler, P. (2007): The deep benthos. In: A. Rogers (ed.): Antarctic Ecology: From Genes to Ecosystems, Royal Society, London. Phil. Trans. R. Soc. B (2007) 362, 39–66.

Brandt, A., Gooday, A.J., Brix S.B., Brökeland, W., Cedhagen, T., Choudhury, M., Cornelius, N., Danis, B., De Mesel, I., Diaz, R.J., Gillan, D.C., Ebbe, B., Howe, J., Janussen, D., Kaiser, S., Linse, K., Malyutina, M., Brandao, S., Pawlowski, J., Raupach, M., (2007): The Southern Ocean deep sea: first insights into biodiversity and biogeography. Nature 447: 307-311.

Ellingsen, K., Brandt, A., Hilbig, B. and K. Linse (2007): The diversity and spatial distribution of polychaetes, isopods and bivalves in the Atlantic sector of the deep Southern Ocean. Polar Biology 30: 1265-1273.

Choudhury, M. and A. Brandt (2007): Distribution and composition of benthic Isopoda off Victoria-Land Coast (Ross Sea, Antarctica). Polar Biology 30: 1431-1437.

Brandt, A., Hilbig, B., Gooday, A.J., (2007): Introduction to ANDEEP, summary and outlook. DSR II, 54: 1645-1651.

Brandt, A., Brökeland, W., Choudhury, M., Brix, S., Kaiser, S and Malyutina, M. (2007): Deep-sea isopod biodiversity, abundance and endemism in the Atlantic sector of the Southern Ocean – results from the ANDEEP I - III expeditions. DSR II, 54: 1760-1775.

Brökeland, W., Choudhury, M. and Brandt, A. (2007): Composition, abundance and distribution of Peracarida from the Southern Ocean deep sea, DSR II, 54: 1752-1759.

Malyutina, M. and Brandt, A. (2007): Diversity and zoogeography of Antarctic deep-sea Munnopsidae (Crustacea, Isopoda, Asellota). DSR II 54: 1790-1805.

Malyutina, M. and Brandt, A. (2007): Gurjanopsis antarcticus gen. nov., sp. nov, a new epibenthic deep-sea munnopsid (Crustacea, Isopoda, Munnopsidae) from the Weddell Sea, Southern Ocean. DSR II 54: 1806-1819.

Raupach, M.J., Malyutina, M., Brandt, A. and Wägele, J. W. (2007): Molecular data reveal a highly diverse species flock within the deep-sea isopod Betamorpha fusiformis (Crustacea: Isopoda: Asellota) in the Southern Ocean. DSR II, 54: 1820-1830.

Linse, K., Brandt, A., Bohn, J., Danis, B., De Broyer, C., Heterier, V., Hilbig, B., Janussen, D., López González, P.J., Schwabe, E., Thomson, M. (2007): Macro- and megabenthic communities in the abyssal Weddell Sea (South Atlantic). DSR II, 54:1848–1863.

Kaiser, S. Barnes, D.K.A. and Brandt, A. (2007): Slope and deep-sea abundance across scales: Southern Ocean isopods show how complex the deep sea can be. DSR II 54: 1776-1789.

Brandt, A. (2008): Leben in Kälte und Dunkel - Wirbellose in der südpolaren Tiefsee. Meer und Museum 20: 114-122.

Brandt, A. (2008): Leben im ewigen Dunkel – Expedition in die Tiefsee des Südozeans. In: D. Fütterer and E. Fahrbach (eds.), „Polarstern – 25 Jahre Forschung in Arktis und Antarktis“, S. 212-220.

Kaiser, S. Barnes, D.K.A, Linse, K. and Brandt, A. (2008): Epibenthic macrofauna associated with the shelf and slope of a young and isolated Southern Ocean island. Antarctic Science 20(3): 281-290.

Brandt, A. and H.G. Andres (2008): A new species of Ischnomesidae (Crustacea: Isopoda) from the Southern Ocean, Stylomesus weddellensis sp. nov. Zootaxa (CeDAMar volume, in press).

Kaiser, S. (2008): First record and new species of the genus Hebefustis Siebenaller and Hessler, 1977 (Isopoda: Asellota: Nannoniscidae) from the deep Weddell Sea Basin. Zootaxa (CeDAMar volume, in press).

Pearse, J. S. Mooi, R. and A. Brandt (in press): Brooding in the Southern Ocean: Selection for brooders or speciation within brooding clades? Smithsonian Contributions to Zoology.

Vey, A. and Brix, S. (accepted): Macrostylis cerritus sp. nov., a new species of Macrostylidae (Isopoda: Asellota) from the Weddell Sea, Southern Ocean. Zootaxa special volume 2 dedicated deep-sea biodiversity.

Research funding organisation

German Science Foundation

Porject nummbers:

Br 1121/20 - ANDEEP I and II 1.7.2001-31.112.2004 (Systematik, Zoogeographie und Evolution antarktischer Tiefseeisopoda)

Br 1121/26 - ANDEEP III 1. 2005-8.2009 (1 Jahr Unterbrechung aufgrund DAAD) (Biodiversity and origin of Antarctic deep-sea Isopoda (Crustacea, Malacostraca))