What’s Going On Here?

Researchers extracting sediment core from the seabed on the south-eastern Weddell Sea made a surprise discovery, when their camera sent down the borehole revealed a life-bearing rock – 16 sponges accompanied by 22 unidentified animals. 

What Does This Mean?

The footage of the boulder shows it is home to at least two types of sponge and other organisms, which could be tube worms or stalked barnacles. On top of that, they also captured a single sponge on another rock nearby which suggests that this single boulder isn’t a one-off. 

According to Huw Griffiths at the British Antarctic Survey, “there’s all sorts of reasons they shouldn’t be there”. Not only are they far from obvious nutrient sources but given what is known about the ocean currents in the area, the nearest up-current source of sunlight appears to be 600 kilometres away. This suggests that life in Antarctica’s harshest environments is more adaptable and more diverse than previously assumed. Despite the fact that studying these animals more closely won’t be easy in such a remote place, lowering down remotely operated vehicles could give us a better idea whether these animals are new to science, how long they live or how often they feed.

Why Should We Care? 

Although the few previous studies of Antarctic marine life from boreholes have found some small mobile organisms – such as fish, worms, jellyfish and krill – they have never found stationary filter-feeders. Instead, they showed a general decrease in overall diversity and the prevalence of sessile organisms with increasing distance from the ice shelf front. In light of their absence, many scientists suspected that the total darkness, the lack of food and the cold temperature was too hostile for them.

Consequently, this accidental discovery of sea life beneath an ice shelf is remarkable in itself and challenges our current understanding of what types of organisms can survive so far from daylight. Learning more about the way these organisms have adapted to their freezing home far from food may also give us an idea about how life evolved hundreds of millions of years ago when the planet was still covered in ice.

The biological and physical attributes that allow them to survive suggest that these communities are either better connected to the outside world than we can currently explain or that the organisms themselves represent highly specialized oligotrophic adaptation. While scientists started to rethink the limits of life in a cold climate, they are also worried that species such as those found on the boulder may fail to respond to rapid changes, such as the collapsing of ice sheets.

Be Curious!

  • Sign this Greenpeace petition and join the movement to create the largest protected area on Earth – an Antarctic Ocean Sanctuary.