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The team at work extracting nematodes from the soil samples. Left to right: Josh Heward, Andy Thompson, Scott George, Byron Adams. Photo by: Walter Andriuzzi

The team at work extracting nematodes from the soil samples. Left to right: Josh Heward, Andy Thompson, Scott George, Byron Adams. Photo by: Walter Andriuzzi

With our short field season in McMurdo already drawing to a close, the team is having a busy time in the Crary Lab in McMurdo. Collecting the samples from the Dry Valleys is only the first step of our job. Down here, most of our working time – actually, most of our time awake – is spent in the lab. Our main tasks after the field missions consist in extracting* and identifying the invertebrates from the soil samples, and running analyses on the physical and chemical properties of the soil. Then, after entering and proofing all the data we have collected into electronic format, we prepare the biological and soil samples for storage and shipping to our labs in the States. Finally, after all work is done, we store our equipment and unused disposables for next year, do a thorough inventory for both our own and the Crary Lab staff’s records, and clear the lab.

With this busy agenda it is easy sometimes to forget the broader picture, but almost daily we have a meeting to keep track of the season’s objectives, and update each other on the progress with the specific tasks. We also find the time to talk about the science – many a fertile idea for a new study has sprung from conversations during mealtime or at the coffee bar.

Scottnema lindsayae left) and Eudorylaimus sp. right) extracted from Dry Valleys soil. Can you identify the sex of this Scottnema? Photo by: Byron Adams.

Adult Scottnema lindsayae left) and juvenile Eudorylaimus sp. right) extracted from Dry Valleys soil. Can you identify the sex of this Scottnema? Photo by: Byron Adams.

Some of our team members may have never seen a live nematode under the microscope before coming here, but by the end of the first or second week all of us are able to identify the nematodes from the Dry Valleys. By the end of the season, some of us will have counted several thousands of nematodes, plus a few rotifers and tardigrades. It is not at all an unpleasant or dull task – to some of us it’s the best part of the whole process (after the field trips). Not only is there life in the soils of the Dry Valleys, but there is also beauty – or at least, interesting action. Check out these two short videos that Josh, our PolarTrec associate, has taken of a rotifer and a tardigrade.

And here is a time-lapse photography video of the team extracting animals from the soil, also by Josh.

 

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Ice is an artist generous with its sculptures. Beyond audience or applause, it creates in profusion for only one reason – that it has need to create.
Jay Griffiths, British writer

Some of nature’s most spectacular works of art are made by ice. What better place to see them than Antarctica, the frozen continent? Below are some highlights of icy art that we were lucky enough to see in and nearby the Dry Valleys.

 

A rare 360° sun halo above Garwood Valley. Picture by: Walter Andriuzzi

A rare full sun halo above Garwood Valley. Photo by: Walter Andriuzzi

The first piece in our gallery was made by the collective effort of millions, billions of tiny artists: ice crystals in the atmosphere refract the sunlight and create a faint rainbow ring around the sun.

 

Blue and white ice in the McMurdo Sound. Picture by: Walter Andriuzzi

Mazes of blue and white ice in the McMurdo Sound. Photo by: Walter Andriuzzi

Most of the ice we see in Antarctica is white (duh!), but as we go to our field sites we often fly over mazes of blue ice in the McMurdo Sound. Blue ice is formed when snow falls on the ice, gets compressed under its own weight, and loses air bubbles, and the ice crystals then expand.

 

Lake Bonney, beautifully frozen. Photo by: Andy Thompson

Lake Bonney, beautifully frozen. Photo by: Andy Thompson

Blue ice can sometimes be seen also in the lakes of the McMurdo Dry Valleys, as in Lake Bonney in the picture above, taken in November 2014. Here you can see the air bubbles, and even the ripples on the water surface, perfectly frozen.

 

Ice stalagmites stalactites on the edge of Canada Glacier, in Taylor Valley. Italian scientist for scale. Picture by: Summer Xue

Ice stalagmites stalactites on the edge of Canada Glacier, in Taylor Valley. Italian scientist for scale. Photo by: Summer Xue

The glaciers in the Dry Valleys are huge monsters of ice, and their fangs are fittingly impressive, easily taller than a person. If you prefer a more peaceful analogy, you may think of them as meditative giants, whose thoughts emerge as music – the dripping and cracking of melting ice.

 

Freeze-dried cyanobacterial mats on a frozen lake surface. Photo by: Andy Thompson

Freeze-dried cyanobacterial mats on a frozen lake surface. Photo by: Andy Thompson

Our last piece is courtesy of a collaboration between ice and life: freeze-dried cyanobacterial mats on the surface of a frozen lake. These formations of microbial and algal biofilms (plus entrapped sediment) are only active for a few weeks per year in the Dry Valleys, when it’s warm enough for liquid water. During the long Antarctic winter, when it’s too cold and dark for photosynthesis, they enter a freeze-dried state to survive. How long can they keep it up? Nobody knows, but at the very least for two decades. And once water comes back, they can reactivate within mere hours.

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The beauty of ice is one of the big attractions of Antarctica. However, beauty may conceal danger. Last week, scientists working elsewhere in Antarctica found that an immense iceberg, as big as the US state of Delaware, is almost ready to break away from western Antarctica. Events such as this will become ever more frequent under climate change, and their cumulative consequences will reach far beyond Antarctica, contributing to the global sea level rise that we are already witnessing.

Written by: Walter Andriuzzi

After a couple of days on hold due to the unpredictable Antarctic weather, today we made it to the field. We split into two teams: Diana, Byron, Josh, and Andy went to Miers Valley, while Ross, Ashley, Walter, Scott, and Matt went to Garwood Valley. The main objective was the same: collect soil samples from elevation transects above the glacial lakes at the bottom of both valleys. This will allow us to find out, firstly, how soil organisms vary in their abundance and diversity as the soil gets farther from the lakes and therefore drier; and secondly, by comparing this year’s data with those we collected in the previous years, to find out how the soil organisms vary in time. Ultimately the aim is to understand how some life forms can make a living in the very challenging conditions of the McMurdo Dry Valleys.

We are often asked how tough fieldwork in Antarctica is. The answer is that working out there can indeed be pretty tough – the cold wind, the UV-packed sunrays, having to hike on fickle terrain –but the rewards are enormous, and not only for the science. Very few places anywhere on the planet can rival the Dry Valleys in terms of grandeur of the scenery. Mountains as tall as the Rockies of Colorado stand behind glaciers taller than the Great Wall of China, and yet they are both made small by the sheer vastness of the place. To the naked eye the place looks barren, but this is one of the key ingredients of its beauty. And as often is the case with nature, this appearance of lifelessness is deceiving.

Ross, Ashley, Matt, and Scott wait for the return helicopter in Garwood Valley. Photo by: Walter Andriuzzi

Ross, Ashley, Matt, and Scott wait for the return helicopter in Garwood Valley. Photo by: Walter Andriuzzi

Garwood Valley, pictured above, is one of the very first sites in the Antarctic Dry Valleys that Ross and Diana went to in 1989, even before the McMurdo Dry Valleys Long Term Ecological Research project was started. Back then, the soils of the Dry Valleys were thought to be sterile, like an enclave of Mars right here on Earth. Well, they are not: as Diana and Ross first found out, and as amply documented by their team in the following 27 years of research, the soils of the McMurdo Dry Valleys host a small yet surprisingly diverse array of very tough critters. Microscopic animals such as nematode worms, rotifers, tardigrades, and in few places springtails (close relative of insects), can and do survive in this ecosystem, and even contribute to the cycling of carbon and nutrients.

Scottnema lindsayae, the most abundant animal in the McMurdo Dry Valleys, Antarctica. Photo by: Byron Adams

Scottnema lindsayae, the most abundant animal in the McMurdo Dry Valleys, Antarctica. Photo by: Byron Adams

In the next couple of weeks we are going to collect samples and maintain experiments in several locations in the Dry Valleys. We’ll experience some intense cold, we may get sunburnt or wind-burnt, and afterwards we’ll work late into the evening in the laboratory – but it will all be worth it.

Written by: Walter Andriuzzi

This season in Antarctica we will be writing blog posts to share our experiences with you. We will be talking about our science, lab & field work, showing what life is like in Antarctica, and answering questions.

View of the helo pad and sea ice from the NSF Chalet at McMurdo Station. Photo by: Walter Andriuzzi

View of the helo pad and sea ice from the NSF Chalet at McMurdo Station. Photo by: Walter Andriuzzi

But, before we dive in to all that, let’s get introduced!

Who are you?  We work together with a group of scientists who study life on the edge of existence in the McMurdo Dry Valleys of Antarctica. On the ice we are known as the “Soil Team,” “C507,” (which is our science event number, like an ID number), or the “Wormherders” (we study nematode worms). The team this year includes: Dr. Diana Wall (CSU), Dr. Byron Adams (BYU), Dr. Ross Virginia (Dartmouth), Dr. Jeb Barrett (VT), Dr. Walter Andriuzzi (CSU), Ashley Shaw (CSU), Andy Thompson (BYU), Scott George (BYU), Josh Heward (PolarTrec), and Matt Hedin (VT).For the 2017 field season, both Walter Andriuzzi and Ashley Shaw will be writing these blog posts for our team. Walter is a post doc and Ashley is a PhD student in Diana Wall’s lab at Colorado State University. You can also find some very cool updates on Josh’s blog, Tough Tardigrades.

What are the McMurdo Dry Valleys? The McMurdo Dry Valleys are one of the coldest and windiest places on the planet. There are no vascular plants, no mammals, no birds, and no fish, who call this place home. There can be cyanobacteria mats or moss in moist places. The largest life forms are microscopic animals called nematodes, tardigrades, rotifers, mites, and collembolans. These animals inhabit soil, moss, and algae. But, we’ll talk more about all the life in the dry valleys later.

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View of the Commonwealth Glacier and Lake Fryxell (on left) from a helicopter in Taylor Valley, Antarctica. Photo by: Ashley Shaw

Who do you work with? We work with the McMurdo Long Term Ecological Research (MCM LTER) project to study the aquatic and terrestrial ecosystem of this (very!) cold desert ecosystem. While our group specializes in soil, there are other teams who study streams, lakes, glaciers, climate, microbiology, environmental history, and geochemistry. The MCM LTER is part of the Long Term Ecological Research (LTER) program. The LTER program is funded by the US National Science Foundation. The aim of this program is to gather long-term data and to study ecological processes that take place over long time scales (10s to 100s of years). Core research areas of this program include: 1) primary production, 2) population studies, 3) movement of organic matter (decomposition and transfer of materials), 4) movement of inorganic matter (e.g., nitrogen, phosphorus), and 5) disturbance patterns. The MCM LTER was begun in 1993 and is one of 26 LTER sites. These sites cover a variety of ecosystems including grasslands, forests, marine, and desert sites. While most of the ecosystems are in the continental U.S., there are two Arctic, several coastal and marine sites, and one other Antarctic site.

Diana Wall talking with Josh Heward, Scott George and Ashley Shaw about nematodes! Photo by: Walter Andriuzzi

Diana Wall talking with Josh Heward, Scott George and Ashley Shaw about nematodes! Photo by: Walter Andriuzzi

You study soil? I thought Antarctica was just a bunch of ice! The McMurdo Dry Valleys are the largest ice-free area in Antarctica. The mountains surrounding the valleys block the glacier ice, keeping the East Antarctic Ice Sheet from filling the valleys. Strong winds, called katabatic winds also contribute to this unique landscape.

Written by: Ashley Shaw

 

Leaving Antarctica is no small feat. We have to break down and store the contents of an entire laboratory (that we set up just weeks earlier). Some items are returned to the Crary Laboratory stockroom, others are put in boxes for “the line” (overwinter storage in big wooden boxes that are kept outside, so things inside must be okay to freeze), extra chemicals are stored in the LTER lab, and finally, the most fragile items are moved into the cage (small locker-like cage that is indoors, so microscope accessories and other fragile items are kept here).

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Example of a box “from the line.” These boxes are filled with our laboratory and sampling equipment and stored outside over the winter. Photo by: Matt Knox

Samples must be prepared for shipment, a process which includes packing, weighing, measuring and labelling boxes, and grappling with an electronic shipping system that is still based on the MS software Access. It’s not only the organisms that live long in Antarctica!

Once everything is packed away, we have to clean – lab space, office space, and our own dorm rooms. Then, these rooms must pass inspection or we have to clean again.

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Walter boarding “Ivan” the Terra Bus for transport. Photo by: Jessica Trout-Haney

Finally, the evening before leaving, we take our own bags to be checked in for our flight. This process is literally officially called “bag drag.” At this time, we find out our transport time for the next morning (it can take over an hour to just get to the plane, so we have to arrive at this time for transport to the airplane). For the last night in McMurdo, you only have your carry-on bag with you – better remember to keep your toothbrush!

Written by: Ashley Shaw

This is a story about living in McMurdo, told in 3 separate parts. This second installment of “A day in the life” will focus on one of the most common questions I get when I tell people about my work in Antarctica – What do you eat? So here it is: eating in McMurdo – where, what and when.

While on station we eat three meals a day in the Galley. The meals are served in a buffet style, but there are two grills where you can sometimes get a burger or eggs cooked how you like. Cereal, coffee, tea, pizza, cookies, and popcorn are available all of the time. There are almost never fresh foods in McMurdo and all food (fruits, vegetables, starches, or meats) come from frozen or dried supplies. We all long for fresh foods, or “freshies” as they are endearingly called here.

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Ashley choosing from the dinner options on the buffet. Photo by: Tandra Fraser

Sunday brunch is the best meal of the week and all the stops are pulled out for this one. We have been lucky this year to get fresh cream on two separate Sundays (a generous gift from the New York National Guard) to have with our coffee for Sunday morning. If any freshies did exist on station, we would probably see them at Sunday brunch (so far, no such luck).

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Ashley getting her Frosty Boy dessert. Look how happy! Photo by: Tandra Fraser

I couldn’t write a blog post about food without talking about frosty boy. Frosty boy is a staple in the Galley and his job is to keep morale high. Yes, our soft serve ice cream machine, complete with sidekicks of myriad sundae toppings, we love him.

 

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Dinner time in McMurdo, taken in the Galley dining area. Photo by: Ashley Shaw

Eating while doing fieldwork is a different story. If you are on a day trip, you have to pack a lunch and snacks to bring with you. There are supplies for this in the Galley, but you must choose them and pack your lunches yourself. If you are staying overnight in the field, it’s your responsibility to plan your own meals and you should arrange to pick up some frozen and dried goods – the choices are up to you! Most established field camps have an indoor area for cooking and eating.

Check back tomorrow for the 3rd and final “day in the life” post. I will tell you a little bit about where we live, sleep, and what we do every day around station!

Written by: Ashley Shaw

Arriving in Antarctica is overwhelming. To be in such an incredibly remote place, surrounded by all of the icy beauty that constant daylight can illuminate, and to be here in the name of science – it’s both an honor and a huge responsibility.

View of McMurdo Station from Observation Hill. Photo: Ashley Shaw

View of McMurdo Station from Observation Hill. Photo: Ashley Shaw

To add to the weight of that responsibility – there is great science taking place all around us. I’ve met scientists who are working on glaciers to try to understand how they move and flow across the continent. Others are taking enormous ice cores to discover what the climate was like many thousands to many millions of years ago. One group is drilling into the icesheet to sample a subglacial lake nearly a kilometer below its surface – and they have found life down there! Some are studying the deep sea, and others are studying deep space. It’s truly incredible just to be here, but it’s even more incredible to be surrounded by this wealth of great minds, thinkers, explorers, scientists… giants in their field of research.

From the top of Observation Hill, Ruth photographs McMurdo Station. Scott's Memorial Cross is in the background. The cross was erected in 1913 in memory of the Scott party who perished while on expedition to the South Pole. Photo: Ashley Shaw

From the top of Observation Hill, Ruth photographs McMurdo Station. Scott’s Memorial Cross is in the background. The cross was erected in 1913 in memory of the Scott party who perished while on expedition to the South Pole. Photo: Ashley Shaw

We work with the Soils Team for Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys. The McMurdo LTER project also has groups that study the valleys’ streams, glaciers, lakes, geology, and climate. Together these teams work to understand the ecosystem in the coldest, windiest and driest desert on the planet. In the soils, we find nematodes, tardigrades, rotifers, protists, bacteria, yeasts, and algae. They rule the valleys. To study these organisms and their ecosystem, we take helicopters from McMurdo Station into the Dry Valleys. This is about a 30 to 45 minute helicopter ride. We collect our samples, monitor and treat our experiments, and return to station to analyze our samples in the lab. The results of our studies are important for understanding how these ecosystems function and respond to change. We contribute to a long-term record that is astounding for it’s breadth of data and its value for ecosystem science.

Sampling soil in the dry valleys. Photo: Ashley Shaw

Sampling soil in the dry valleys. Photo: Ashley Shaw

Of course there are limitations to working in this extreme environment – I’m constantly asked what it’s like to be here. But, if there’s one thing I could tell my friends and family back home – besides the weather (yes, it’s cold!), the living conditions (yes, there are bathrooms and electricity!), and the daily penguin updates (No, I haven’t seen any yet) – it would be that this is a place of great science. And it’s an honor to be here amongst the giants.

Written by: Ashley Shaw

Our first priority this season is the sampling and treatment of the Pulse and Press Project (P3). This experiment has been running for three years already, and this will be the first sampling opportunity after treatments have been applied. To briefly summarize, this work investigates the effect of increased subsurface water flow on soil biota and other soil parameters. Last year we collected a third year of baseline data and were interested in the logistics of how best to apply the water in a controlled way. This involved pumping water uphill from a nearby pond and into a holding tank, where it was sterilized and applied back down slope to the plots. https://nemablog.wordpress.com/2014/01/14/p3-a-success/

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The P3 experiment site at Many Glaciers Pond, Taylor Valley, Antarctica. Photo: Matt Knox 2014.

This time around, one year later, we get to see how the biological community responded to the treatments. We are planning to sample tomorrow and have been very busy getting the lab ready and preparing for a busy day taking samples in the field. If sampling goes well, we’ll be back in the lab analyzing soil communities and looking for changes in species composition (who is where), population shifts (growing or shrinking) and population structure (gender and life stage ratios). These results will tell us if the treatments we are applying are changing the ecology of the study area and give insight into how the whole Dry Valley ecosystem might respond to climate change.

Written by: Matt Knox

Welcome to Nemablog 2014/15! This season we all got to have Christmas at home with our families before beginning the long journey south. After a relatively uneventful 30-hour journey from the US we finally arrived, tired and bewildered in Christchurch, New Zealand. Of course it would not be an Antarctic field season without some drama, so we were not surprised to find that the airline had lost three of our bags on the way to New Zealand. We only stayed in Christchurch for a couple of days so we were faced with the prospect of leaving for Antarctica without them. After a much needed sleep, we went to the Antarctic clothing distribution center, where we were issued our extreme weather clothes and got to watch several short videos, designed to prepare us for our time on the ice. 

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The clothing distribution center in Christchurch. Photo: Ruth Heindel.

After that there was some time to soak up some lovely New Zealand weather and New Years’ Eve celebrations before the flight to the ice the following day. Next morning we were ready to board the C-130 aircraft operated by the US military. Thankfully all of the missing bags had been located and could join us. Now it was time to leave the fair shores of New Zealand for a month in a less hospitable climate. The 8 hour flight to the ice went off without a hitch, with us landing near McMurdo Station on the ice runway – into gorgeous sunny, clear and warm (about 30F), meaning that this season would begin as planned!

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First view of Antarctica from window of C130 aircraft. Photo: Ruth Heindel.

Right now we are settling into McMurdo Station and preparing the lab for the season ahead. Everyone is very excited about the science we have been planning for the last few months and will enjoy adding updates to this blog as the work progresses. Watch the weather and McMurdo at the webcam http://www.wunderground.com/webcams/webcamstraveldot/21087/show.html

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The Wormherders have landed – Jan 1 2015. Photo: Ruth Heindel.

Written by: Matt Knox

Though we spend a good amount of time in the field, a lot of our time is also spent in the lab, analyzing the invertebrates in the soil samples for each field experiment. We do this by processing and counting nematodes and the other microorganisms we see down here.

Processing essentially just means extracting the nematodes from the soil matrix, so we can easily see them under the microscope. It’s a fairly simple process that involves three members of the team working together in an assembly line. First, each sample is weighed inside a laminar flow hood then divided for extraction for nematodes and soil moisture analysis. To measure the amount of water in the soil, a small amount of soil is weighed, placed in an oven, dried, then weighed again. Soil moisture is an important indicator of life in this ecosystem, and is very useful for interpreting the results of our experiments later on.

The other portion of soil goes off to a second person to be filtered: we mix the soil in water and then apply the muddy mixture to two sieves of different sizes, stacked on top of each other. The top sieve has holes large enough to let nematodes through, but too small for most of the dirt and rocks. The bottom sieve uses a mesh fine enough to catch nematodes and similarly sized dirt particles, but allows really fine grains to fall out of the sample.

Next, the third person in the line takes four filtered samples and centrifuges them all at once: the centrifuge pulls all the soil and the nematodes down to the bottom of the container so that we can pour out any leftover water. When that’s done, we add a sugar solution that is key to the whole process. The sugar separates the nematodes from the dirt and sand, pulling them up into a supernatant that can be selectively removed, leaving behind the unwanted soil. This is possible because of density: the nematodes are as dense as the sugar and float, while the rocks and the dirt are denser and sink. Once the sugar is added, the samples are passed back to the person doing the sieving, who removes sugar by filtering them in running water through a very fine sieve and placing the final solution (containing both water and nematodes)into tubes that are immediately refrigerated. The entire extraction process can be very stressful on the organisms in the samples, and so we try and do everything we can to get them through as quick as possible and back into a more natural environment (the fridge).

After processing, each sample is analyzed under the microscope and every animal is identified to species and life stage (male, female and juvenile) and living or dead and counted. This can take only a few minutes (if the sample is completely empty) or nearly an hour. There are three main species of nematode here in the Dry Valleys that we deal with in the lab: Scottnema lindsayae, Eudorylaimus antarcticus, and Plectus murrayi. Scottnema is by far the most common because most of the soils are very dry; the other two species need more moisture and thus show up much more rarely. Sometimes, w e also see rotifers and tardigrades, as well as tiny single-celled eukaryotes like ciliates and amoeba.

When we compare the species that are present in each sample to the moisture content of the sample, we begin to see patterns of how the physical factors of the soil affect species composition (which species are present in a given location). When we take these patterns from year to year and compare them to records of weather and climate we begin to see long-term patterns of how climate shifts and extreme events (like hot summers and subsequent valley “flooding” events) influence the ecology of the organisms living in these valleys. This is one of the main tools, and objectives, of the McMurdo Dry Valley LTER.

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This is a species of Eudorylaimus; they are usually much longer than Scottnema or Plectus nematodes.

 

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This is Scottnema lindsayae; these are only found in Antarctica and like the other nematodes there (Plectus, Eudorylaimus) are capable of surviving due to anyhydrobiosis, which allows them to expel the water in their body and roll into a tight ball and reduce their surface exposure to wind and cold. Tardigrades and rotifers can also enter anhydrobiosis.

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This is a species of rotifer; compared to the nematodes in these valleys, very little is known about Rotifers. They get their name because the cilia on their mouths move in a way that it looks like they have rotors on their heads.

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This is the front half of a tardigrade. Tardigrades have 8 legs and are related to nematodes and arthropods (like insects and spiders). They are also known as Water Bears and can be found in mosses almost anywhere in the world.

 

 

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This is protist found in the Dry Valleys. Protists are single-celled eukaryotes (meaning they have a nucleus), and are even less understood than rotifers in these valleys. Unlike the other pictures, I took this photo this season, with just my phone camera and a microscope. I have no idea what species it is! It could even be new to science, which would make it an exciting discovery.

 

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