Unimaginable diversity of life discovered beneath Antarctic ice shelf

Live Science ^ | Cmaeron Duke

[BenLurkin]

As most ecosystems are built on a foundation of photosynthetic organisms like plants or algae, such dark realms shouldn't have enough food to support a wide variety of life.

In such a dark and seemingly inhospitable environment, the team found fragments of living organisms. When they realized that they had found more than they expected, Claus-Dieter Hillenbrand, a sedimentologist with the British Antarctic Survey, recommended sending the seafloor sample to Barnes.

The pieces that had been pulled from underneath the ice shelf, when examined with a microscope, were clearly from different animals. All told, Barnes identified 77 different species, far more than he should have reasonably found. This one sample was even richer with species than he would have expected from a survey of the open shelf.

Many of the species identified were bryozoans, or stationary filter feeders that often look like a brain or moss, such as Melicerita obliqua and tube-feeding worms such as Paralaeospira sicula, among others. "This discovery of so much life living in these extreme conditions is a complete surprise and reminds us how Antarctic marine life is so unique and special," Barnes told Live Science.

Finding such rich life underneath the ever-present ice sheet is one thing, but explaining why it is there is another matter entirely. Marine life, especially filter feeders like bryozoans, sponges and jellyfish, should, in theory, become scarcer with distance from the open sea; that's because they feed on algae, which needs sunlight, and because they were thought to be too delicate for the brutal 28 degrees Fahrenheit (minus 2.2 degrees Celsius) temperatures.

But it turns out these animals are feasting on microorganisms like ciliates and dinoflagellates that are swept underneath the ice shelf by oceanic currents.

[Seruzawa]

Oh jeez. I forgot. Not that his appearance would make things much worse.