The Antarctic Sun, November 26, 2006

November 26, 2006 The Antarctic Sun • 3 Team uncovering strengths of ‘How do they do that?’ Antarctica’s toughest resident By Steven Profaizer Sun staff Very few creatures can claim to be as tough as Antarctica’s largest year-round land animal. It can survive extreme dehydration, freezing and weeks without oxy- gen. So, which beast can withstand such a bruising and be the reigning king of Antarctica? Belgica antarctica – a flightless fly. This 7- to 8-millimeter-long midge lives on the Antarctica Peninsula and lays claim to the title of the insect distributed farthest south in the world. “Why can it survive here where we don’t find other insects? How can you be Photos courtesy of Robert Lee / Special to The Antarctic Sun tolerant to so many stresses all at once Above, two specimens of Belgica antarctica and still be able to undergo normal feed- mate during their brief lifespan as adults. ing and growth?” said Rick Lee, principal The species is the most southerly distrib- investigator of a science project studying uted insect in the world and has the ability this incredible survivor. “We’re here look- to withstand a wide spectrum of environ- ing at an animal that’s absolutely living mental stressors. on the edge at a place where other insects cannot survive.” Left, Rick Lee is the principal investigator This is Lee’s second stint on a project for the project studying the coping capa- studying the midge’s coping capabilities. bilities of the Antarctic midge. He first came to Antarctica as a post-doc- toral fellow in 1981 and documented the being produced at the same time that nor- Unlike many other chironomids, which midge’s tolerance to various environmen- mal growth, feeding and developing were fly briefly during their life cycle, the tal stressors. occurring.” Antarctic midge remains wingless. “The plan for our new project, some 25 Only a few animals demonstrate this Wings are certainly an important trait years later, is to come back and take a look ability, and Lee said all of them, includ- of flies, but Lee said the rest of a midge’s at these adaptations with new molecular ing a fish and a protozoan, live in the anatomy keeps it firmly in the fly cat- tools and more sophisticated physiologi- Antarctic. Lee said he wants to try to egory. And since its relatives have wings, cal techniques to address, ‘how do they do discover why that is the case – is living the Antarctic midge probably had them at that?’” he said. in the Antarctic so constantly hard on the some point and lost them secondarily. Lee is collaborating with Dave system that some animals require these “It’s very expensive to support flight Denlinger from The Ohio State University proteins all of the time, or is it that they muscles and wings, and without them they for his current project. Their research are exposed to intermittent periods of can use that energy for growth and repro- focuses on the midges’ resistance to extreme conditions and so they have to be duction instead,” Lee said. “If you take a extreme temperatures and dehydration prepared? look at many insects that live on islands, – both observations with roots in the 1981 It takes two years of growing and mountaintops or places where it’s very project in which he was involved. feeding for the midges to complete their windy, there’s strong natural selection “You could dry a midge out to 35 metamorphosis to adulthood. They have against flight. We often see a reduction in percent of it normal body mass,” he said. a spotty distribution on the Antarctic flight muscles and a shortening of wings “It shriveled up like a little raisin, but yet Peninsula and can be located in a variety – a tendency toward flightlessness. In this when you added water to it, it plumped of microhabitats. Lee’s group has found case, it went as far as to completely do back up, wiggled away and was doing just them in conjunction with algae, penguin away with the wings.” fine.” guano and an Antarctic grass. Lee said he hopes that the unassuming The project is in its third year, and “They really get into a lot of differ- midge may allow us to learn more about new molecular techniques have allowed ent habitats,” Lee said. “It suggests that how it can be so tough, specifically when researchers to identify the year-round maybe generalists do better in really rigor- it comes to the freezing of its tissue. There presence of stress proteins. ous, living-at-the-edge environments.” are only a few animals that can withstand Such proteins are only activated in most After the midges make it to adulthood, freezing without sustaining damage, and organisms when cells are under stress. the payoff is short-lived, as they only have most of them have that ability to a much When this response occurs, cells normally seven to 10 days to mate and lay eggs lesser degree than the midge. shut down all their routine forms of pro- before they die. “If we study freeze-tolerant models,” tein production, but the midge appears to Belgica antarctica is part of the Lee said, “they may give us some clues … be producing these stress proteins while Chironomidae family, a group of insects as to how we might cryopreserve human its cells continue to function normally. well known for its stamina. Polypedilum tissues and organs.” “It tends to be you’re either in a stress vanderplanki, another member of this mode and trying to survive or it’s business family, is found in African deserts and can NSF-funded research in this story: Rick as usual,” Lee said. “It was remarkable lose 99 percent of it body mass to dehy- Lee, Miami University, www.units.muohio. to find that these stress proteins were dration and live to tell the tale. edu/cryolab/education/antarctic.htm..

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