The origin of life is surely one of the most important questions in biology. How did inanimate molecules give rise to the “endless forms most beautiful” that we see today, and where did this event happen? Some of the most popular theories suggest that life began in a hellish setting, in rocky undersea vents that churn out superheated water from deep within the earth. But a new paper suggests an alternative backdrop, and one that seems like the polar opposite (pun intended) of the hot vents –ice.
Like the vents, frozen fields of ice seem like counter-intuitive locations for the origin of life – they’re hardly a hospitable environment today. But according to James Attwater form the University of Cambridge, ice has the right properties to fuel the rise of “replicator” molecules, which can make copies of themselves, change and evolve.
Say the word iceberg, and most people are likely to free-associate it with ‘Titanic’. Thanks to James Cameron (and, well, history too), the iceberg now has a reputation as an cold murderous force of nature, sinking both ships and Leonardo DiCaprio. But a new study shows that icebergs are not harbingers of death but hotspots of life.
In the late 1980s, about 200,000 icebergs roamed across the Southern Ocean. They range in size from puny ‘growlers’, less than a metre long, to massive blocks of ice, larger than some small countries.
They may be inert frozen lumps, but icebergs are secretly in the business of nutrient-trafficking. As the ice around Antarctica melts in the face of global warming, some parts break free from the parent continent and strike out on their own. As they melt, they release stored minerals into the water around them, and these turn them into mobile homes for a variety of life.
Kenneth L. Smith Jr, from the Monterey Bay Aquarium Research Institute, and other scientists from San Diego discovered the true extent of these icy ecosystems by studying two icebergs floating in the Antarctic Weddell Sea. Even the smaller of the two, W-86, has a surface area larger than 17 football pitches. The larger one, A-52 was over a thousand times bigger, with a surface area of 300 km2 and extending 230 metres into the freezing waters.
Smith and crew identified the duo through satellite imaging, and tracked them down by boat. Their ship spiralled around the blocks of ice collecting water samples as it went, from a dangerously close distance of a few hundred feet to a safer five miles away.