Iceland, the land of volcanic eruptions, glacial fields, and herds of grazing sheep, does not welcome plant life with open arms. The ones that do slip through the cracks (quite literally sometimes) are often marvels of evolutionary accomplishment. The marimo, a big fuzzy ball of algae that dwells in the shallow waters of Mývatn, is such a plant. It’s one of those weirdo, outcast plants, the kind that other plants gawk at in the photos ynthesis line: they do not know the latest fashions of fruit or flowers, the sport of root growing, nor the lingo of leaves. But perhaps the marimo’s huggable form or their lush, calming green hue, often adorned by pearls of air bubbles, might win you over.
GETTING TO KNOW THE MARIMO
Marimos are the creative limits of evolution in the flesh. And for this, us nerdy naturalists are utterly enamoured with them. However, according to Árni Einarsson, director of The Mývatn Research Station, an ecological research institute that monitors Lake Mývatn, the “marimo has no place in Icelandic culture.” Only until relatively recently, he says, were they known to people outside of the Mývatn area. But to be fair, scientists only discovered the colony that inhabits the lake in 1977.
When gazing upon a marimo, one might wonder how the elements of nature convinced algae, an organism that prefers a more planar existence, to take the form of a perfect sphere. Normally plants want to increase their surface area-to-volume ratio (e.g. with big leaves or lots of pine needles) to capture as much light as possible for their size. Spheres are really bad at maximizing this ratio; actually, they’re the worst. The marimo, however, has gotten around this staple rule of evolution. They took the hypotenuse line to survival: require less light (thus, energy) to live by staying small. The marimos in Mývatn reach only about 10 to 12 cm in diameter.
Though scientists aren’t completely sure how they form, they think it involves the gentle caresses of wind-induced waves over Mývatn, the silky sediments of Icelandic volcanoes, and the light conditions of life at the bottom of a clear lake. When these three factors combine, marimos leave the psychedelic dreams of a young botanist’s slumbers and materialise here in Iceland and only a few other locations on earth, including Japan’s Lake Akan. Like Mývatn, Akan was formed by volcanic activity, which might explain why large colonies of marimos call both lakes home.
English speakers actually adapted the Japanese word for these algal balls, ‘marimo,’ as their own. The direct Japanese translation is quite literal: ‘mari’ meaning ‘ball’ and ‘mo’ meaning ‘water plant.’ The direct translation of the Icelandic word, ‘kúluskítur,’ is a bit less endearing. ‘Kúlu’ translates to ‘ball’ and ‘skítur’ means ‘shit’ in Icelandic. “Fishermen often used vulgar names for strange things that come to the surface when fishing,” says Árni, and in the marimo’s case, they were probably deemed shit because they would get “entangled in the fishing nets but [aren’t] fish,” he says. So for Icelandic fishermen, not fish = shit. Makes sense.
LET US IN
Maybe what stunts any growth of respect for marimos in Iceland is their elusive behaviour. In order to see one of these guys in the wild, you’d have to be lucky enough to hook one on a fishing line or be part of a registered diving operation. The Natural History Museum in Kópavogur does have some on display in a tank, but that’s not really the same as seeing scores of them piled on top of each other in Mývatn.
Though their exterior allows for quick judgement, the marimo’s interior deserves the respect of many far and wide. It is evolutionary fitness at it greatest: break one of these guys open and out comes a torrent of chloroplasts that in a matter of hours will awaken from a dark hibernation. After these chloroplasts see the light, they become photosynthetically active and start producing energy that the marimo uses to make one broken ball into two shiny new balls.
NEVER GONNA GIVE UP
The way to kill a marimo may require a slow, insidious approach. Us humans are accomplishing this quite successfully, scientists believe. Marimo populations are declining worldwide. Though they aren’t exactly sure how, biologists have a hunch that the decline involves eutrophication, which is the build up of nutrients caused by either natural sources, like bacteria, or human sources, like fertilizer runoff. Eutrophication can make lakes foggy, which hinders the amount of light that reaches the things living at the bottom of the lake.
The situation in Iceland is bit more complicated, where during the winter months everyone’s got to learn to live with little sunlight. If the marimos can survive months without sunlight, then a little extra fogginess can’t be the cause of their decline, Icelandic scientists reason. Basically, what we’ve got here is a case of the elusive outcast, shunned by society, which only leads to more secrecy. The marimo has stumped the scientific community, not only concerning the cause of its decline but also the basics of its life cycle. But there are a few of us that take a fancy to your elusiveness, little Icelandic marimo, and we will continue chip at the wall you have built around yourself until we reach the emerald core of your biology.