Deep beneath Antartica's glaciers are extensive subglacial cave networks formed by steam from active volcanos. These mysterious caves are still mostly unexplored and scientists haven't truly uncovered what kinds of ecosystems they could hold. However, a team at Australian National University has examined soil samples for traces of DNA and revealed these caves could hold a much a more diverse set of known, and unknown, organisms than previously thought.
Mount Erebus is an active volcano on Ross Island containing extensive subglacial cave systems formed by volcanic steam. Researchers have hypothesized that a broad variety of organisms could be nurtured within these geothermal areas, but there has been little study into these potentially novel ecosystems until now.
A team from ANU has now discovered fascinating DNA traces in soil samples from these mysterious caves, revealing evidence of mosses, algae and invertebrates. While some of the DNA traces found have been discovered previously, the team could not fully identify all the sequences sampled, leading to conclusions that these cave systems may hold entirely new species of plants and animals.
"It can be really warm inside the caves - up to 25 degrees Celsius (77° F) in some caves," explains lead researcher Dr Ceridwen Fraser. "You could wear a t-shirt in there and be pretty comfortable. There's light near the cave mouths, and light filters deeper into some caves where the overlying ice is thin."
With more than 15 active, or recently active, volcanos in Antarctica, this research suggests the potential for diverse and complex organisms to have evolved in these dynamically unique systems. As well as finding a variety of eukaryotic invertebrate and plant species, the study posits that more sophisticated macrofauna could exist in these environments.
The research also has fascinating implications in the search for life on other planets. Evidence of complex organisms on Earth in these volcanic cave systems could direct scientists to new off-Earth targets.
"The next steps will be to take a closer look at the caves and search for living organisms," says co-researcher Prof Laurie Connell. "If they exist, it opens the door to an exciting new world."
The research was published in the journal Polar Biology.
Source: Australian National University
