|Kymella polaris, a cheilostome bryozoan, at 32m depth. Credit: BAS|
In the latest issue of 'Current Biology', researchers from the British Antarctic Survey (BAS) have published an analysis of growth rates of a tiny sea animal.
Samples of the bryozoan, (Cellarinella nutti) a sea-bed filter-feeding animal that looks like branching twigs, collected during Captain Scott's Antarctic trips, are yielding data that may prove valuable in projecting climate change, BBC News is reporting.
The samples were collected in the Ross Sea, where Capt. Robert Falcon Scott moored during both the Discovery expedition of 1901-04 and the Terra Nova expedition a decade later, where he lost his life attempting to return from the South Pole.
These early 20th century expeditions brought back many finds including samples of life from the sea floor. Comparing these samples with modern ones, scientists have now shown that the growth of the bryozoan has increased in recent years.
Growing during the period in the year when it can feed by drawing plankton from the water with its tentacles, the length of the feeding season is reflected in the size of the annual growth band, similar to tree rings.
Bryozoan samples, collected at the same site recently by the Census of Marine Life, have increased the flow of data over the past decade allowing researchers to show that the creatures grew roughly the same amount each year until about 1990.
Since then, there has been a steady increase, with the annual growth rate now being more than double the 20th century average. BAS scientists claim this means that the bryozoans are now eating longer, which means they are eating more phytoplankton - the tiny marine plants that draw dissolved CO2 from seawater.