how do you burrow
through hard ice, anemone, with
Tuesday, January 21, 2014
In late 2010 a geological expedition to Antarctica drilled through the Ross Ice Shelf so they could send an ROV under it. What they found was unexpected: Sea anemones. In their thousands they were doing what no other species of sea anemone is known to do — they were living in the ice itself.
Discovered by the ANDRILL [Antarctic Drilling] project, the team was so unprepared for biological discoveries they did not have suitable preservatives and the only chemicals available obliterated the creature’s DNA. Nonetheless Marymegan Daly of Ohio State University confirmed the animals were a new species. Named Edwardsiella andrillae after the drilling project that found it, the anemone was finally described in a PLOS ONE paper last month.
ANDRILL lowered their cylindrical camera ROV down a freshly-bored 270m (890ft) hole, enabling it to reach seawater below the ice. The device was merely being tested ahead of its planned mission retrieving data on ocean currents and the sub-ice environment. Instead it found what ANDRILL director Frank Rack of the University of Nebraska–Lincoln, a co-author of the paper describing the find, called the “total serendipity” of “a whole new ecosystem that no one had ever seen before”.
The discovery raises many questions. Burrowing sea anemones worm their way into substrates or use their tentacles to dig, but it’s unclear how E. andrillae enters the hard ice. With only their tentacles protruding into the water from the underneath of the ice shelf questions also revolve around how the animals avoid freezing, how they reproduce, and how they cope with the continuously melting nature of their home. Their diet is also a mystery.
“What fascinates me about sea anemones is that they’re able to do things that seem impossible”
E. andrillae is an opaque white, with an inner ring of eight tentacles and twelve-to-sixteen tentacles in an outer ring. The ROV’s lights produced an orange glow from the creatures, although this may be produced by their food. It measures 16–20mm (0.6–0.8in) but when fully relaxed can extend to triple that.
Genetic analysis being impossible, Daly turned to dissection of the specimens but could find nothing out of the ordinary. Scientists hope to send a biological mission to explore the area under the massive ice sheet, which is in excess of 600 miles (970km) wide. The cameras also observed worms, fish that swim inverted as if the icy roof was the sea floor, crustaceans and a cylindrical creature that used appendages on its ends to move and to grab hold of the anemones.
NASA is providing funding to aid further research, owing to possible similarities between this icy realm and Europa, a moon of Jupiter. Biological research is planned for 2015. An application for funding to the U.S. National Science Foundation, which funds ANDRILL, is also pending.
The ANDRILL team almost failed to get any samples at all. Designed to examine the seafloor, the ROV had to be inverted to examine the roof of ice. Weather conditions prevented biological sampling equipment being delivered from McMurdo Station, but the scientists retrieved 20–30 anemones by using hot water to stun them before sucking them from their burrows with an improvised device fashioned from a coffee filter and a spare ROV thruster. Preserved on-site in ethanol, they were taken to McMurdo station where some were further preserved with formaldehyde.
Read the very interesting Wikinews interview with Marymegan Daly on the unusual new sea anemone!