Just over one hundred years ago in Feburary 1911, Captain R.F. Scott RN received news from Roald Amundsen that he was intending to make a bid for the South Pole in competition with Scott’s. Scott’s expedition had a range of important scientific goals: the race for the Pole for which he is best known was only one of the objectives. The science involved resulted in a number of Antarctic collections, some of which are in the Museum today.
These collections have been used to show a dramatic doubling in the growth of bryozoans in Antarctic seas in the last twenty years. Bryozoans are tiny colonial animals that encrust rocks, algae and other objects beneath the sea, filtering food from the water. It is another use of older collections that could never have been anticipated at the time of collection, but shows the value and importance of these collections to modern science and current concerns.
Dr Piotr Kuklinski, a Scientific Associate of the Museum who works for the Polish Academy of Sciences Institute of Oceanography, has collaborated with other scientists from the British Antarctic Survey and US institutions to examine collections to tell how growth has changed over time and to suggest reasons why this might be happening.
They looked at a whole series of Antarctic collections in the Museum from 1909 to the 1930s, and other collections in the US and New Zealand up to the present day. The species Cellarinella nutti from the Ross Sea was used – it shows annual growth lines as the colony expands and so yearly growth can be measured. The growth measurements showed no particular change in rates of growth from 1890 to 1970, but there was a rapid increase in growth from the 1990s to the present day.
Why is this happening? Growth seems to be increasing because of increased availability of food – tiny single-celled plants known as phytoplankton. This increase would result from higher concentrations of phytoplankton or a longer growing season. Climate change? Probably not - the scientists point out that there is little evidence of changes to sea ice or water temperatures in the Ross Sea.
However, they do suggest that this may be linked to depletion of stratospheric ozone – the ozone holes that occur in the Antarctic summer. This could be causing stronger west winds that result in currents bringing in more nutrients to the area, in turn resulting in higher growth of plankton and higher growth of bryozoans. Our understanding of the detail of these questions helps refine our understanding of the Earth’s carbon cycle, which is closely linked to our climate system.
The authors conclude ‘Amundsen claimed that Scott's “..British expedition was designed entirely for scientific research. The Pole was only a side-issue…”. Being first to reach the pole was foremost in fundraising and probably in Scott's thinking but coming second in the ensuing ‘race’ and dying there completely overshadowed the many scientific achievements of the expedition. However, the baselines that they established and crucial subsequent curation may prove key to interpretation of trends with significance way beyond the polar regions.’
David K.A. Barnes, Piotr Kuklinski, Jennifer A. Jackson, Geoff W. Keel, Simon A. Morley, Judith E. Winston (2011) Scott's collections help reveal accelerating marine life growth in Antarctica. Current Biology - 22 February 2011 (Vol. 21, Issue 4, pp. R147-R148) doi:10.1016/j.cub.2011.01.033