Many researchers working in Antarctica study large things. The ice lakes and glaciers are so massive that the glaciologists who study them may find it easier to use airplanes rather than tons as unit of measure. Oceanographers and climatologists track down icebergs larger than some countries. Volcanologists are checking the vital signs of that formidable giant that is Mount Erebus (3794 m above sea level, more than 12 thousand feet). Astronomers look out of the clear Antarctic skies to stars and galaxies.
Many biologists study large and easily recognized creatures such as seals, penguins, and whales. But where we “Wormherders” are conducting research there are no living things that the naked eye can see. We are focusing on much smaller creatures, such as nematode worms. Virtually all soils on Earth host nematodes, but in the Dry Valleys very few species occur, and they are specially adapted to this extreme environment. The same goes for the microscopic algae and the bacteria living in lakes and soils that other teams in McMurdo are studying. Some of the most exciting ecological questions in Antarctica are about very small things indeed.
(Admittedly, even nematodes and microbes may be described as very large by the particle physicists working on “AMANDA”, the Antarctic Muon and Neutrino Detecting Array. There truly is science for all sizes at McMurdo.)
The McMurdo Dry Valleys seem as desolate and lifeless a place as one could conceive. But take a scoop of soil from almost anywhere in the valleys, subject it to an appropriate extraction process, put the resulting water solution under a microscope, and there you go: living creatures, more abundant and active than you might suspect.
Scottnema lindsayae, one of the most abundant residents of the McMurdo Dry Valleys. A female and a male caught in the act of mating. Photo by Jessica Trout-Haney
Some of us have been busy all day identifying and counting specimens from samples we collected last week. It’s not at all boring as some might suspect, partly because of the beauty of the organisms we look at. Nematodes bend, coil and stretch elegantly on the microscope plate. Scottnema lindsayae, the most abundant, performs what may look like some contemporary dance. Less common but hard to miss, the much larger Eudorylaimus antarcticus flexes slowly, like a microscopic python waking from sleep. A Plectus sp. with its head inside a dead rotifer, busy scavenging on bacteria inside the decomposing body, looks like it has put on a mask to scare the others around it.
Nematodes dominate this playground, but there is more. Rotifers scurry, hop and cartwheel across the plate like pesky children, sometimes playing tug-of-war with nematodes over lumps of organic matter. Even faster than rotifers, a ciliate slides effortlessly, in shape and motion somewhat similar to a flying saucer (or a swimming saucer). Tardigrades move clumsily on their short legs, but don’t be fooled by their cute appearance – they are some of the toughest creatures on Earth.
Some team members load scientific equipment and supplies on the helicopter that will take them from Lake Hoare Camp to another location in the Dry Valleys. Photo by Walter Andriuzzi
It was not an easy job to collect these biological samples. The helicopter is the only means on transport to get from McMurdo to the Dry Valleys. Flights have to be planned days in advance with the crew, but often they need to be rescheduled due to the unpredictable weather. Once in the Valleys, the Wormherders have to move fast to finish sampling before the helicopter returns (but it also helps against freezing).
Sometimes daily trips aren’t enough. Thankfully for us, there are a handful of well-equipped camping sites in the Dry Valleys. Last week we spent a night at Lake Hoare Camp, managed by Rae Spain and Renee Noffke – a homely, warm place in a land of ice giants and sharp winds. The landscape around the camp is so spectacular that some of our team, despite being quite tired from the day’s work, couldn’t resist the temptation of an after-dinner hike. We walked along Canada Glacier, past mummified seals and ice stalactites, and on to the moraine on the side of the glacier, and eventually we stepped on the glacier (with the appropriate footwear!).
Lake Hoare Camp, an important logistics base for researchers working in the McMurdo Dry Valleys. Photo by Walter Andriuzzi
There might seem to be a paradox – on one hand the size and majesty of the Dry Valleys, and on the other hand the minuscule beauty of the fauna that inhabits those soils. But such is the greatness of ecology, a science that connects the small and the large, the hidden and the obvious. With a bit of assistance from the weather, we’ll be collecting more samples from the Dry Valleys in the next few days, and who knows what surprises we might find under a microscope. In the meantime, some team members are camping near Lake Fryxell in Taylor Valley, taking care of one of the most exciting ecological experiments undergoing in Antarctica.
by Walter Andriuzzi