NATO's Underground Roman Super-Quarry

[Image: An entrance to the quarry in Kanne; photo by Nick Catford via Subterranean Britannica].

There is an underground Roman-era quarry in The Netherlands that, when you exit, you will find that you have crossed an invisible international border somewhere down there in the darkness, and that you are now stepping out into Belgium; or perhaps it's the other way around, that there is an underground Roman-era quarry in Belgium that, when you exit, you will find that you have crossed an invisible international border somewhere down there in the darkness, and that you are now stepping out into The Netherlands.

However, this is not just a disused quarry—not just an archaeological site on the fringes of the Roman empire that was once mined for blocks of limestone. Its afterlife is by far the most interesting part of the story.

For nearly a century, beginning in the 1800s, these underground hollows were used by Jesuit monks as a secluded place for prayer, study, and meditation, and even for the carving of elaborate and impressive forms into the soft rock walls; then the Nazis took over, transforming this weird underworld into a subterranean factory for World War II airplane parts; then, finally, pushing the stakes yet higher, the whole complex of former Roman limestone mines, straddling an international border underground between two modern European nations, was turned into a doomsday bunker for NATO, a dark and mold-prone labyrinth within which military commanders constructed a Joint Operations Center for responding to the end of the world (whenever the time finally came).

[Images: Monks underground; via De Limburgse Mergelgrotten].

"There was even a 3-hole golf course complete with artificial turf," Subterranean Britannica reports in a recent issue of their excellent magazine, Subterranea.

"The complex was on average 50 meters below ground covering an area of approximately 6750 acres with eight miles of corridors, 400 branches and 399 individual offices," SubBrit explains. There were escape tunnels, as well, "one going out to the banks of the Albert Canal in Belgium, and one which came out in a farmer's potato store in the village of Kanne." It had its own water supply and even a dedicated wine cellar for NATO officers, who might need a glass of Europe's finest chardonnay to help feel calm enough to launch those missiles.

Just look at this thing's mind-boggling floor plan.

The "streets" were named, but not always easy to follow; however, this didn't stop officers stationed there from occasionally going out to explore the older tunnels at night. A former employee named Bob Hankinson describes how he used to navigate:

Most corners were roughly 90 degrees, but only roughly. Going through the caves was an exercise in left and right turns every 50 feet or so. Navigation was helped by street names. Unlike in the USA, where streets are numbered on a sort of grid pattern, these were zigzag streets. My office on Main Street and J Street, so if I got lost I would just keep walking until I came to either Main or J, and join it. If I went the wrong way, eventually the street would peter out either at the perimeter or a T-junction, and you would just turn round and go back the other way.

As another former employee—a man named Alan Francis—explains, "If I did have spare time, I would wander through the dark tunnels where there were very few lights on at night, thinking how strange it was to be working in a Roman stone quarry."

Writing in Subterranea, SubBrit explains that "nothing ever came out." This was "a strict rule: apart from people, anything that went in never came out. All waste material ranging from redundant furniture to foot waste was dumped in one of the sixteen underground landfill sites" designated within this sprawling whorl of rooms and passages. Shredded documents were even mixed with water and applied directly to the walls as a kind of fibrous paste, used for insulation.

Such was the secrecy surrounding this place that it was officially classified as "a 'forbidden place' under the Protection of State Secrets Act which forbade people to even talk about it."

One reason why the underground galleries are so vast, meanwhile, is apparently because of the character of the limestone they were carved through; in fact, "the limestone was so soft that the workers used a chainsaw to cut it."

The notion that I could just cut myself a whole new room with a chainsaw—just revving this thing up and carving an entire new hallway or corridor, pushing relentlessly forward into what looks like solid earth, possibly even sawing my way into the roots of another country—is so awesome an architectural condition that I would move there tomorrow if I could.

Just imagine building this titanic doorway into the earth with a small group of friends, a case of beer, and a few chainsaws. It's like Cappadocia by way of the Cold War. By way of Husqvarna.

[Image: An entrance into the NATO complex; via this thread].

Sadly, the whole place is contaminated with asbestos and has been badly saturated with diesel fuel. At least one environmental analysis of the underground maze found that "diesel fuel from the [copious emergency fuel] tanks had leaked into the porous limestone over a long period and had penetrated to a depth of about forty feet into the rock."

You can imagine the weird bonfires that could have resulted should someone have been stupid enough to light a match, but "this area had to be removed and disposed of," we read—presumably by chainsaw.

Nonetheless, today you can actually take a tour of this place—this now-derelict doomsday logistics hub that straddles international borders underground—courtesy of the Limburg Landscape Foundation.

If you can take the tour, let me know how it goes; I'd love to visit this place in person someday and would be thrilled to see any photographs.

(If you like the sound of underground NATO quarries and want to see more, don't miss these vaguely related photo sets: NATO Quarry, N.A.T.O. Quarry, N.A.T.O. Quarry, France, Urban Explorers Discover Corroding Military Vehicles in Abandoned Subterranean Bunker, and Nato Quarry, Paris Suburbs May 2011).

Landmarks of the Chinese Cryosphere

Nicola Twilley of Edible Geography (and also my wife) spent a large part of this past winter exploring the world of artificial refrigeration in China for The New York Times. The results of that trip are now out in this weekend's New York Times Magazine, called "The Price of Cold," and she's put together an accompanying travelogue on Edible Geography that takes you to "Ten Landmarks of the Chinese Cryosphere."

These new spatial monuments to the control of thermal energy include the dreamlike "Room of the Sleeping Fish" in Jinan, which sounds like something out of an early Rupert Thomson novel, where live fish are effectively refrigerated into a state of hibernation during which they can survive outside of water; the delightful, Willy Wonka-like "Yogurt Control Room" in Tianjin, where vats of active bacteria grow and proliferate under laboratory supervision; the more or less self-explanatory Beijing Vegetable Research Center; and a variety of wet markets, shops, and restaurants where you, too, can experience the electrically-powered, human-induced winter that is slowly spreading its tentacles across the nation.

The Most Indoors

[Image: Inside NYC's old post office, Instagram by BLDGBLOG].

"Suppose we define an indoors number as the number of doorways that one must pass through to get from a given location to the outdoors. What location has the highest number?"

What room in the world is the furthest indoors?

Beneath the Forest, Buildings

[Image: Photo by Heiko Prumers, courtesy of LiveScience].

The remains of artificial structures that pre-date the Amazon rainforest have been found beneath the trees in Bolivia and Brazil. The forest actually grew up and around their ruins, we read, gradually consuming these structures altogether as the rainforest we see there today slowly spread over hundreds of years and conquered the landscape.

"A series of square, straight and ringlike ditches scattered throughout the Bolivian and Brazilian Amazon were there before the rainforest existed," LiveScience reported earlier this month.

Based on the research of a postdoctoral graduate student named John Francis Carson, the report suggests that "the diggers of these ditches created them before the forest moved in around them. They continued to live in the area as it became forested, probably keeping clear regions around their structures."

[Image: Photo by Heiko Prumers, courtesy of LiveScience].

One of the most intriguing suggestions of the study is that the rainforest we see there today is actually, at its origins, what Carson calls "a coproduction between humans and nature."

"It's very likely, in fact," he explains, "that people had some kind of effect on the composition of the forest... People might favor edible species, growing in orchards and things like that, [or] altered the soils, changing the soil chemistry and composition, which can have a longer-lasting legacy effect."

In other words, the deliberate, long-term selection and cultivation of plant species preferred by humans would have led to a distinct type of forest growing in the region, not just a "wild" expanse of whatever plants could naturally survive.

The ancient forest was pruned, tended, and gardened, Carson's research suggests, and therefore has a kind of unnatural origin, not unlike an abandoned garden gone to seed.

[Image: Photo by Heiko Prumers, courtesy of LiveScience].

In fact, this brings to mind the fascinating work of UC Berkeley anthropologist Christine Hastorff, who has pointed out that many of the heavily vegetated Central American landscapes we inaccurately and over-simplistically describe as "rainforest" are actually "feral gardens": plots of artificially cultivated plants, vines, and trees, similar to orchards, that only later took on the appearance of wilderness after their gardeners were exterminated by Europeans.

Hastorff—like Carson—suggests that traces of this human-induced artificiality at the scale of an entire ecosystem can still be detected in the landscape, following detailed investigations into what combinations of plants grow in what areas, and then comparing these to what we would expect to see growing without human interference. These landscapes are not really wild forests at all, then, Hastorff explains, but "Maya village community garden plants that have gone feral. That isn’t the forest that was there before humans landed in the Americas."

In any case, Carson's work on the "mysterious earthen rings" found beneath the tree cover of the Brazilian and Bolivian Amazon is certainly fascinating for its glimpse of human settlement patterns—that is, architecture—hidden beneath an incredible landscape. However, its even more intriguing take away is that this very landscape was—at least in part—cultivated and influenced by the people who built the "earthen rings" we see in these photographs. Developing the implications of this "has only just started," he tells LiveScience.

Bunker Simulations

[Image: A replica of the Nazis' Atlantic Wall defenses in Scotland; photo via Stirling 2014].

The continent-spanning line of concrete bunkers built by the Nazis during WWII, known as the "Atlantic Wall," was partially recreated in the United Kingdom—in more than one location—to assist with military training.

These simulated Nazi bunkers now survive as largely overlooked ruins amidst the fields, disquieting yet picturesque earth forms covered in plants and lichen, their internal rebar exposed to the weather and twisted by explosives, serving as quiet reminders of the European battlefield.

The various wall sites even include trenches, anti-tank ditches, and other defensive works carved into the ground, forming a kind of landscape garden of simulated fortification.

[Image: A replica of the Atlantic Wall in Scotland; photo via Stirling 2014].

As the Herald Scotland reported the other day, one of these walls "was built at Sheriffmuir, in the hills above Dunblane, in 1943 as preparations were being made to invade Europe. The problem was the Nazis had built a formidable line of concrete defenses from Norway all the way to the Spanish border and if D-Day was to have any chance of success, the British and their allies would have to get over those defenses."

This, of course, "is why the wall at Sheriffmuir was built: it was a way for the British forces to practise their plan of attack and understand what they would face. They shot at it, they smashed into it, and they blew it up as a way of testing the German defences ahead of D-Day."

[Image: A replica of the Atlantic Wall in Scotland; photo via Stirling 2014].

It would certainly be difficult to guess what these structures are at first glance, or why such behemoth constructions would have been built in these locations; stumbling upon them with no knowledge of their history would suggest some dark alternative history of WWII in which the Nazis had managed to at least partially conquer Britain, leaving behind these half-buried fortresses in their wake.

Indeed, the history of the walls remains relatively under-exposed, even in Britain, and a new archaeological effort to scan all of the defenses and mount an exhibition about them in the Dunblane Museum is thus now underway.

[Image: A replica of the Atlantic Wall in Scotland; photo via Stirling 2014].

The story of the Scottish wall's construction is also intriguingly odd. It revolves around an act of artistic espionage, courtesy of "a French painter and decorator called Rene Duchez."

Duchez, the newspaper explains, "got his hands on the blueprints for the German defences while painting the offices of engineering group TODT, which [had been hired] to build the Atlantic walls. He hid the plans in a biscuit tin, which was smuggled to Britain and used as the blueprint for the wall at Sheriffmuir."

But Scotland is not the only UK site of a simulated Nazi super-wall: there were also ersatz bunkers built in Surrey, Wales, and Suffolk. In fact, the one in Surrey, built on Hankley Common, is not all that far from my in-laws, so I'll try to check it out in person next time I'm over in England.

[Images: An Atlantic Wall replica in Surrey; top photo by Shazz, bottom three photos via Wikipedia].

Attempts at archaeological preservation aside, these walls seem destined to fade into the landscape for the next several millennia, absorbed back into the forests and fields; along the way, they'll join other ancient features like Hadrian's Wall on the itinerary of future military history buffs, just another site to visit on a slow Sunday stroll, their original context all but forgotten.

(Spotted via Archaeology. Previously on BLDGBLOG: In the Box: A Tour Through The Simulated Battlefields of the U.S. National Training Center and Model Landscape].

The Museum At The Bottom Of The Sea

[Image: Photo by Martin Siegel/Society of Maritime Archaeology, via Der Spiegel].

In 2012, German archaeologists began posting interpretive signs underwater, marking shipwrecks and even crashed airplanes at the bottom of the Baltic Sea as if they are in a museum, in order to make it clear to potential vandals, reckless tourists, and amateur collectors that these are culturally important sites, worthy of preservation.

"Alarmed at the looting of historically valuable shipwrecks in the Baltic Sea," Der Spiegel reported at the time, "German archaeologists have started attaching underwater signs designating them as protected monuments. Hobby divers and trophy hunters are damaging a precious maritime legacy stretching back thousands of years, they warn."

The sunken ship seen in the above image, for example, is just one of "some 1,500 marine monuments strewn across the seabed along the coast. The area has a wealth of well-preserved shipwrecks, lost cargo planes and even ancient settlements submerged through subsidence and rising water levels." That these can be described as monuments is very important: they are not mere wreckage, scattered over the seabed, but artifacts on display for those who can reach them.

[Image: Photo by Martin Siegel/Society of Maritime Archaeology, via Der Spiegel].

The effect is strangely evocative, as if an architectural experiment has been going on beneath the waves of the Baltic Sea for the last few years, in which a museum, entirely without walls and seemingly with only very few visitors, has been secretly installed and constructed. It is a distributed, nonlinear museum of European ruins barely visible in the rising sea.

What's so interesting from an architectural standpoint, however, is how a group of signs such as these can have such a huge narrative and spatial effect, as if you've entered some sort of undefined volumetric space without walls, hidden in the water all around you, a kind of invisible cultural institution stocked with objects that only you and your fellow divers, at that exact moment, can even see.

In fact, it makes me curious how the (totally brilliant and BLDGBLOG-supported) idea of creating a new National Park on the moon might work—and, more to the point, what such a park would really look like. Do we just post a few signs on the lunar surface indicating that historically important artifacts are present up ahead, or do we actually construct some sort of "museum" space there that would more adequately sustain an aura of cultural history?

Either way, it's both hilarious and deeply strange that we could begin to experiment with what such a park might look like using—of all things—shipwrecks at the bottom of the Baltic Sea, and that German archaeologists, randomly posting cheap signs on the seabed, might have anticipated future strategies of historic preservation in otherwise deeply unearthly situations.

Life on the Subsurface: An Interview with Penelope Boston

A landscape painting above Penny Boston's living room entryway depicts astronauts exploring Mars.

Penelope Boston is a speleo-biologist at New Mexico Tech, where she is also Director of Cave and Karst Science. Her work examines subterranean lifeforms, often found very deep within cave systems, including the larger subterranean ecosystems those creatures are connected to. Her research focuses primarily on what are known as extremophiles for their ability to survive in seemingly inhospitable micro-environments here on Earth; these bizarre forms of life, thriving in acidic, anoxic, or highly pressurized situations, offer compelling analogies for the sorts of lifeforms and ecosystems that might exist, undetected, on other planets.

But the flip side of her research are those environments themselves: the caves, tunnels, and other underground spaces inside of which unearthly life might thrive. As you'll see, this is an interview obsessed with space: how to define space, how space is formed geologically, and what sorts of speculative underground spaces and structures can form under radically different gravitational regimes, deep inside the polar glaciers of distant moons, or even in the turbulent skies of gas giants.

Boston has worked with the NASA Innovative Advanced Concepts program (NIAC) to develop protocols for both human extraterrestrial cave habitation and for subterranean life-detection missions on Mars, life which she believes is highly likely to exist.

On a hot summer afternoon, she graciously welcomed me and Nicola Twilley, traveling for our Venue project, into her home in Los Lunas, New Mexico, where we arrived with design futurist Stuart Candy in tow, en route to dropping him off at the Very Large Array later that day.

Over the course of our conversation, Boston told us about her experiences working at Mars analog sites; she explained why she believes there is a strong possibility for life below the surface of the Red Planet, perhaps inside billion-year-old networks of lava tubes; she detailed her own ongoing cave explorations beneath the U.S. Southwest; and we touched on some mind-blowing ideas seemingly straight out of science fiction, including extreme forms of extraterrestrial life (such as dormant life on comets, thawed and reawakened with every passage close to the sun) and the extraordinary potential for developing new pharmaceuticals out of cave microorganisms.

An edited transcript of our conversation appears below.

• • •
The Flashline Mars Arctic Research Station (FMARS) on Devon Island, courtesy of the Mars Society.

Geoff Manaugh: As a graduate student, you co-founded the Mars Underground and then the Mars Society. You’re a past President of the Association of Mars Explorers, and you’re also now a member of the science team taking part in Mars Arctic 365, a new one-year Mars surface simulation mission set to start in summer 2014 on Devon Island. How does this long-term interest in Mars exploration tie into your Earth-based research in speleobiology and subterranean microbial ecosystems?

Penelope Boston: Even though I do study surface things that have a microbial component, like desert varnish and travertines and so forth, I really think that it’s the subsurface of Mars where the greatest chance of extant life, or even preservation of extinct life, would be found.

Nicola Twilley: Is it part of NASA’s strategy to go subsurface at any point, to explore caves on Mars or the moon?

Boston: Well, yes and no. The “Strategy” and the strategy are two different things.

The Mars Curiosity rover is a very capable chemistry and physics machine and I am, of course, dying to hear the details of the geochemistry it samples. A friend of mine, for instance, with whom I’m also a collaborator, is the principal investigator of the SAM instrument. Friends of mine are also on the CheMin instrument. So I have a vested interest, both professionally and personally, in the Curiosity mission.

On the other hand, you know: here we go again with yet another mission on the surface. It’s fascinating, and we still have a lot to learn there, but I hope I will live long enough to see us do subsurface missions on Mars and even on other bodies in the solar system.

Unfortunately, right now, we are sort of in limbo. The downturn in the global economy and our national economy has essentially kicked NASA in the head. It’s very unclear where we are going, at this point. This is having profound, negative effects on the Agency itself and everyone associated with it, including those of us who are external fundees and sort of circum-NASA.

On the other hand, although we don’t have a clear plan, we do have clear interests, and we have been pursuing preliminary studies. NASA has sponsored a number of studies on deep drilling, for example. One of the most famous was probably about 15 years ago, and it really kicked things off. That was up in Santa Fe, and we were looking at different methodologies for getting into the subsurface.

I have done a lot of work, some of which has been NASA-funded, on the whole issue of lava tubes—that is, caves associated with volcanism on the surface. Now, Glenn Cushing and Tim Titus at the USGS facility in Flagstaff have done quite a bit of serious work on the high-res images coming back from Mars, and they have identified lava tubes much more clearly than we ever did in our earlier work over the past decade.

Surface features created by lava tubes on Mars; image via ESA

Twilley: Is it the expectation that caves as common on Mars as they are on Earth?

Boston: I’d say that lava tubes are large, prominent, and liberally distributed everywhere on Mars. I would guess that there are probably more lava tubes on Mars than there are here on Earth—because here they get destroyed. We have such a geologically and hydro-dynamically active planet that the weathering rates here are enormous.

But on Mars we have a lot of factors that push in the other direction. I’d expect to find tubes of exceeding antiquity—I suspect that billions-of-year-old tubes are quite liberally sprinkled over the planet. That’s because the tectonic regime on Mars is quiescent. There is probably low-level tectonism—there are, undoubtedly, Marsquakes and things like that—but it’s not a rock’n’roll plate tectonics like ours, with continents galloping all over the place, and giant oceans opening up across the planet.

That means the forces that break down lava tubes are probably at least an order of magnitude or more—maybe two, maybe three—less likely to destroy lava tubes over geological time. You will have a lot of caves on Mars, and a lot of those caves will be very old.

Plus, remember that you also have .38 G. The intrinsic tensile strength of the lava itself, or whatever the bedrock is, is also going to allow those tubes to be much more resistant to the weaker gravity there.

Surface features of lava tubes on Mars; images via ESA

Manaugh: I’d imagine that, because the gravity is so much lower, the rocks might also behave differently, forming different types of arches, domes, and other formations underground. For instance, large spans and open spaces would be shaped according to different gravitational strains. Would that be a fair expectation?

Boston: Well, it’s harder to speculate on that because we don’t know what the exact composition of the lava is—which is why, someday, we would love to get a Mars sample-return mission, which is no longer on the books right now. [sighs] It’s been pushed off.

In fact, I just finished, for the seventh time in my career, working on a panel on that whole issue. This was the E2E—or End-to-End—group convened by Dave Beatty, who is head of the Mars Program at the Jet Propulsion Laboratory [PDF].

About a year ago, we finished doing some intensive international work with our European Space Agency partners on Mars sample-return—but now it’s all been pushed off again. The first one of those that I worked on was when I was an undergraduate, almost ready to graduate at Boulder, and that was 1979. It just keeps getting pushed off.

I’d say that we are very frustrated within the planetary and astrobiology communities. We can use all these wonderful instruments that we load onto vehicles like Curiosity and we can send them there. We can do all this fabulous orbital stuff. But, frankly speaking, as a person with at least one foot in Earth science, until you’ve got the stuff in your hands—actual physical samples returned from Mars—there is a lot you can’t do.

Looking down through a "skylight" on Mars and into a Martian sinkhole; images via NASA/JPL/University of Arizona

Twilley: Could you talk a bit about your work with exoplanetary research, including what you’re looking for and how you might find it?

Boston: [laughs] The two big questions!

But, yes. We are working on a project at Socorro now to atmospherically characterize exoplanets. It’s called NESSI, the New Mexico Exoplanet Spectroscopic Survey Instrument. Our partner is Mark Swain, over at JPL. They are doing it using things like Kepler, and they have a new mission they’re proposing, called FINESSE. FINESSE will be a dedicated exoplanet atmospheric characterizer.

We are also trying to do that, in conjunction with them, but from a ground-based instrument, in order to make it more publicly accessible to students and even to amateur astronomers.

That reminds me—one of the other people you might be interested in talking to is a young woman named Lisa Messeri, who just recently finished her PhD in Anthropology at MIT. She’s at the University of Pennsylvania now. Her focus is on how scientists like me to think about other planets as other worlds, rather than as mere scientific targets—how we bring an abstract scientific goal into the familiar mental space where we also have recognizable concepts of landscape.

I’ve been obsessed with that my entire life: the concept of space, and the human scaling of these vastly scaled phenomena, is central, I think, to my emotional core, not just the intellectual core.

The Allan Hills Meteorite (ALH84001); courtesy of NASA.

Manaugh: While we’re on the topic of scale, I’m curious about the idea of astrobiological life inhabiting a radically, undetectably nonhuman scale. For example, one of the things you’ve written and lectured about is the incredible slowness it takes for some organisms to form, metabolize, and articulate themselves in the underground environments you study. Could there be forms of astrobiological life that exist on an unbelievably different timescale, whether it’s a billion-year hibernation cycle that we might discover at just the wrong time and mistake, say, for a mineral? Or might we find something on a very different spatial scale—for example, a species that is more like a network, like an aspen tree or a fungus?

Boston: You know, Paul Davies is very interested in this idea—the concept of a shadow biosphere. Of course, I had also thought about this question for many years, long before I read about Davies or before he gave it a name.

The conundrum you face is: how would you know—how you would study or even conceptualize—these other biospheres? It’s outside of your normal spatial and temporal comfort zone, in which all of your training and experience has guided you to look, and inside of which all of your instruments are designed to function. If it’s outside all of that, how will you know it when you see it?

Imagine comets. With every perihelion passage, volatile gases escape. You are whipping around the solar system. Your body comes to life for that brief period of time only. Now apply that to icy bodies in very elliptical orbits in other solar systems, hosting life with very long periods of dormancy.

There are actually some wonderful early episodes of The Twilight Zone that tap into that theme, in a very poetic and literary way. [laughs] Of course, it’s also the central idea of some of the earliest science fiction; I suppose Gulliver’s Travels is probably the earliest exploration of that concept.

In the microbial realm—to stick with what we do know, and what we can study—we are already dealing with itsy-bitsy, teeny-weeny things that are devilishly difficult to understand. We have a lot of tools now that enable us to approach those, but, very regularly, we’ll see things in electron microscopy that we simply can’t identify and they are very clearly structured. And I don’t think that they are all artifacts of the preparation—things that get put there accidentally during prep.

A lot of the organisms that we actually grow, and with which we work, are clearly nanobacteria. I don’t know how familiar you are with that concept, but it has been extremely controversial. There are many artifacts out there that can mislead us, but we do regularly see organisms that are very small. So how small can they be—what’s the limit?

A few of the early attempts at figuring this out were just childish. That’s a mean thing to say, because a lot of my former mentors have written some of those papers, but they would say things like: “Well, we need to conduct X, Y, and Z metabolic pathways, so, of course, we need all this genetic machinery.” I mean, come on, you know that early cells weren’t like that! The early cells—who knows what they were or what they required?

To take the famous case of the ALH84001 meteorite: are all those little doobobs that you can see in the images actually critters? I don’t know. I think we’ll never know, at least until we go to Mars and bring back stuff.

I have relatively big microbes in my lab that regularly feature little knobs and bobs and little furry things, that I am actually convinced are probably either viruses or prions or something similar. I can’t get a virologist to tell me yes. They are used to looking at viruses that they can isolate in some fashion. I don’t know how to get these little knobby bobs off my guys for them to look at.

The Allan Hills Meteorite (ALH84001); courtesy of NASA.

Twilley: In your paper on the human utilization of subsurface extraterrestrial environments [PDF], you discuss the idea of a “Field Guide to Unknown Organisms,” and how to plan to find life when you don’t necessarily know what it looks like. What might go into such a guide?

Boston: The analogy I often use with graduate students when I teach astrobiology is that, in some ways, it’s as if we are scientists on a planet orbiting Alpha Centauri and we are trying to write a field guide to the birds of Earth. Where do you start? Well, you start with whatever template you have. Then you have to deeply analyze every feature of that template and ask whether each feature is really necessary and which are just a happenstance of what can occur.

I think there are fundamental principles. You can’t beat thermodynamics. The need for input and outgoing energy is critical. You have to be delicately poised, so that the chemistry is active enough to produce something that would be a life-like process, but not so active that it outstrips any ability to have cohesion, to actually keep the life process together. Water is great as a solvent for that. It’s probably not the only solvent, but it’s a good one. So you can look for water—but do you really need to look for water?

I think you have to pick apart the fundamental assumptions. I suspect that predation is a relatively universal process. I suspect that parasitism is a universal process. I think that, with the mathematical work being done on complex, evolving systems, you see all these emerging properties.

Now, with all of that said, the details—the sizes, the scale, the pace, getting back to what we were just talking about—I think there is huge variability in there.

Caves on Mars; images courtesy of NASA/JPL-Caltech/ASU/USGS.

Twilley: How do you train people to look for unrecognizable life?

Boston: I think everybody—all biologists—should take astrobiology. It would smack you on the side of the head and say, “You have to rethink some of these fundamental assumptions! You can’t just coast on them.”

The organisms that we study in the subsurface are so different from the microbes that we have on the surface. They don’t have any predators—so, ecologically, they don’t have to outgrow any predators—and they live in an environment where energy is exceedingly scarce. In that context, why would you bother having a metabolic rate that is as high as some of your compatriots on the surface? You can afford to just hang out for a really long time.

We have recently isolated a lot of strains from these fluid inclusions in the Naica caves—the one with those gigantic crystals. It’s pretty clear that these guys have been trapped in these bubbles between 10,000 and 15,000 years. We’ve got fluid inclusions in even older materials—in materials that are a few million years old, even, in a case we just got some dates for, as much as 40 million years.

Naica Caves, image from the official website. The caves are so hot that explorers have to wear special ice-jackets to survive.

One of the caveats, of course, is that, when you go down some distance, the overlying lithostatic pressure of all of that rock makes space impossible. Microbes can’t live in zero space. Further, they have to have at least inter-grain spaces or microporosity—there has to be some kind of interconnectivity. If you have organisms completely trapped in tiny pockets, and they never interact, then that doesn’t constitute a biosphere. At some point, you also reach temperatures that are incompatible with life, because of the geothermal gradient. Where exactly that spot is, I don’t know, but I’m actually working on a lot of theoretical ideas to do with that.

In fact, I’m starting a book for MIT Press that will explore some of these ideas. They wanted me to write a book on the cool, weird, difficult, dangerous places I go to and the cool, weird, difficult bugs I find. That’s fine—I’m going to do that. But, really, what I want to do is put what we have been working on for the last thirty years into a theoretical context that doesn’t just apply to Earth but can apply broadly, not only to other planets in our solar system, but to one my other great passions, of course, which is exoplanets—planets outside the solar system.

One of the central questions that I want to explore further in my book, and that I have been writing and talking about a lot, is: what is the long-term geological persistence of organisms and geological materials? I think this is another long-term, evolutionary repository for living organisms—not just fossils—that we have not tapped into before. I think that life gets recycled over significant geological periods of time, even on Earth.

That’s a powerful concept if we then apply it to somewhere like Mars, for example, because Mars does these obliquity swings. It has super-seasonal cycles. It has these little dimpled moons that don’t stabilize it, whereas our moon stabilizes the Earth’s obliquity level. That means that Mars is going through these super cold and dry periods of time, followed by periods of time where it’s probably more clement.

Now, clearly, if organisms can persist for tens of thousands of years—let alone hundreds of thousands of years, and possibly even millions of years—then maybe they are reawakenable. Maybe you have this very different biosphere.

Manaugh: Like a biosphere in waiting.

Boston: Yes—a biosphere in waiting, at a much lower level.

Recently, I have started writing a conceptual paper that really tries to explore those ideas. The genome that we see active on the surface of any planet might be of two types. If you have a planet like Earth, which is photosynthetically driven, you’re going to have a planet that is much more biological in terms of the total amount of biomass and the rates at which this can be produced. But that might not be the only way to run a biosphere.

You might also have a much more low-key biosphere that could actually be driven by geochemical and thermal energy from the inside of the planet. This was the model that we—myself, Chris McKay, and Michael Ivanoff, one of our colleagues from what was the Soviet Union at the time—published more than twenty years ago for Mars. We suggested that there would be chemically reduced gases coming from the interior of the planet.

That 1992 paper was what got us started on caves. I had never been in a wild cave in my life before. We were looking for a way to get into that subsurface space. The Department of Energy was supporting a few investigators, but they weren’t about to share their resources. Drilling is expensive. But caves are just there; you can go inside them.

Penelope Boston caving, image courtesy of V. Hildreth-Werker, from "Extraterrestrial Caves: Science, Habitat, Resources," NIAC Phase I Study Final Report, 2001.

So that’s really what got us into caving. It was at that point where I discovered caves are so variable and fascinating, and I really refocused my career on that for the last 20 years.

The first time I did any serious caving was actually in Lechuguilla Cave. It was completely nuts to make that one’s first wild cave. We trained for about three hours, then we launched into a five-day expedition into Lechuguilla that nearly killed us! Chris McKay came out with a terrible infection. I had a blob of gypsum in my eye and an infection that swelled it shut. I twisted my ankle. I popped a rib. Larry Lemke had a massive migraine. We were not prepared for this. The people taking us in should have known better. But one of them is a USGS guide and a super caving jock, so it didn’t even occur to him—it didn’t occur to him that we were learning instantaneously to operate in a completely alien landscape with totally inadequate skills.

Lechuguilla Cave, photograph by Dave Bunnell.

All I knew was that I was beaten to a pulp. I could almost not get across these chasms. I’m a short person. Everybody else was six feet tall. I felt like I was just hanging on long enough so I could get out and live. I've been in jams before, including in Antarctica, but that’s all I thought of the whole five days: I just have to live through this.

But, when I got out, I realized that what the other part of my brain had retained was everything I had seen. The bruises faded. My eye stopped being infected. In fact, I got the infection from looking up at the ceiling and having some of those gooey blobs drip down into my eye—but, I was like, “Oh my God. This is biological. I just know it is.” So it was a clue. And, when, I got out, I knew I had to learn how to do this. I wanted to get back in there.

ESA astronauts on a "cave spacewalk" during a 2011 training mission in the caves of Sardinia; image courtesy of the ESA.

Manaugh: You have spoken about the possibility of entire new types of caves that are not possible on Earth but that might be present elsewhere. What are some of these other cave types you think might exist, and what sort of conditions would be required to form them? You’ve used some great phrases to describe those processes—things like “volatile labyrinths” and “ice volcanism” that create strange cave types that aren’t possible on Earth.

Boston: Well, in terms of ice, I’ll bet there are all sorts of Lake Vostok-like things out there on other moons and planets.

The thing with Lake Vostok is that it’s not a "lake." It’s a cave: a cave in ice. The ice, in this case, acts as bedrock, so it’s not a lake at all. It’s a closed system.

Manaugh: It’s more like a blister: an enclosed space full of fluid.

Boston: Exactly. In terms of speculating on the kinds of caves that might exist elsewhere in the universe, we are actually working on a special issue for the Journal of Astrobiology right now, based on the extraterrestrial planetary caves meeting that we did last October. We brought people from all over the place. This is a collaboration between my Institute—the National Cave and Karst Research Institute in Carlsbad, where we have our headquarters—and the Lunar and Planetary Institute.

The meeting was an attempt to explore these ideas. Karl Mitchell from JPL, who I had not met previously, works on Titan; he’s on the Cassini Huygens mission. He thinks he is seeing karst-like features on Titan. Just imagine that! Hydrocarbon fluids producing karst-like features in water-ice bedrock—what could be more exotic than that?

That also shows that the planetary physics dominates in creating these environments. I used to think that the chemistry dominated. I don’t think so anymore. I think that the physics dominates. You have to step away from the chemistry at first and ask: what are the fundamental physics that govern the system? Then you can ask: what are the fundamental chemical potentials that govern the system that could produce life? It’s the same exercise with imagining what kind of caves you can get—and I have a lurid imagination.

From "Human Utilization of Subsurface Extraterrestrial Environments," P. J. Boston, R. D. Frederick, S. M. Welch, J. Werker, T. R. Meyer, B. Sprungman, V. Hildreth-Werker, S. L. Thompson, and D. L. Murphy, Gravitational and Space Biology Bulletin 16(2), June 2003.

One of the fun things I do in my astrobiology class every couple of years is the capstone project. The students break down into groups of four or five, hopefully well-mixed in terms of biologists, engineers, chemists, geologists, physicists, and other backgrounds.

Then they have to design their own solar system, including the fundamental, broad-scale properties of its star. They have to invent a bunch of planets to go around it. And they have to inhabit at least one of those planets with some form of life. Then they have to design a mission—either telescopic or landed—that could study it. They work on this all semester, and they are so creative. It’s wonderful. There is so much value in imagining the biospheres of other planetary bodies.

You just have to think: “What are the governing equations that you have on this planet or in this system?” You look at the gravitational value of a particular body, its temperature regime, and the dominant geochemistry. Does it have an atmosphere? Is it tectonic? One of the very first papers I did—it appeared in one of these obscure NASA special publications, of which they print about 100 and nobody can ever find a copy—was called “Bubbles in the Rocks.” It was entirely devoted to speculation about the properties of natural and artificial caves as life-support structures. A few years later, I published a little encyclopedia article, expanding on it, and I’m now working on another expansion, actually.

I think that, either internally, externally, or both, planetary bodies that form cracks are great places to start. If you have some sort of fluid—even episodically—within that system, then you have a whole new set of cave-forming processes. Then, if you have a material that can exist not only in a solid phase, but also as a liquid or, in some cases, even in a vapor phase on the same planetary body, then you have two more sets of potential cave-forming processes. You just pick it apart from those fundamentals, and keep building things up as you think about these other cave-forming systems and landscapes.

ESA astronauts practice "cavewalking"; image courtesy ESA-V. Corbu.

Manaugh: One of my favorite quotations is from a William S. Burroughs novel, where he describes what he calls “a vast mineral consciousness at absolute zero, thinking in slow formations of crystal.”

Boston: Oh, wow.

Manaugh: I mention that because I’m curious about how the search for “extraterrestrial life” always tends to be terrestrial, in the sense that it’s geological and it involves solid planetary formations. But what about the search for life on a gaseous planet, for example—would life be utterly different there, chemically speaking, or would it simply be sort of dispersed, or even aerosolized? I suppose I’m also curious if there could be a “cave” on a gaseous planet and, if so, would it really just be a weather system? Is a “cave” on a gaseous planet actually just a storm? Or, to put it more abstractly, can there be caves without geology?

Boston: Hmm. Yes, I think there could be. If it was enclosed or self-perpetuating.

Manaugh: Like a self-perpetuating thermal condition in the sky. It would be a sort of atmospheric “cave.”

Twilley: It would be a bubble.

ESA astronauts explore caves in Sardinia; image courtesy ESA–R. Bresnik.

Boston: In terms of life that could exist in a permanent, fluid medium that was gaseous—rather than a compressed fluid, like water—Carl Sagan and Edwin Salpeter made an attempt at that, back in 1975. In fact, I use their "Jovian Gasbags" paper as a foundational text in my astrobiology classes.

But an atmospheric system like Jupiter is dominated—just like an ocean is—by currents. It’s driven by thermal convection cells, which are the weather system, but it’s at a density that gives it more in common with our oceans than with our sky. And we are already familiar with the fact that our oceans, even though they are a big blob of water, are spatially organized into currents, and they are controlled by density, temperature, and salinity. The ocean has a massively complex three-dimensional structure; so, too, does the Jovian atmosphere. So a gas giant is really more like a gaseous ocean I think.

Now, the interior machinations that go on in inside a planet like Jupiter are driving these gas motions. There is a direct analogy here to the fact that, on our rocky terrestrial planet, which we think of as a solid Earth, the truth is that the mantle is plastic—in fact, the Earth’s lower crust is a very different substance from what we experience up here on this crusty, crunchy top, this thing that we consider solid geology. Whether we’re talking about a gas giant like Jupiter or the mantle of a rocky planet like Earth, we are really just dealing with different regimes of density—and, here again, it’s driven by the physics.

ESA astronauts set up an experimental wind-speed monitoring station in the caves of Sardinia; image courtesy ESA/V. Crobu.

A couple of years ago, I sat in on a tectonics class that one of my colleagues at New Mexico Tech was giving, which was a lot of fun for me. Everybody else was thinking about Earth, and I was thinking about everything but Earth. For my little presentation in class, what I tried to do was think about analogies to things on icy bodies: to look at Europa, Titan, Enceledus, Ganymede, and so forth, and to see how they are being driven by the same tectonic processes, producing the same kind of brittle-to-ductile mantle transition, but in ice rather than rock.

I think that, as we go further and further in the direction of having to explain what we think is going on in exoplanets, it’s going to push some of the geophysics in that direction, as well. There is amazingly little out there. I was stunned, because I know a lot of planetary scientists who are thinking about this kind of stuff, but there is a big gulf between Earth geophysics and applying those lessons to exoplanets.

ESA astronauts prepare for their 2013 training mission in the caves of Sardinia; image courtesy ESA-V. Crobu.

Manaugh: We need classes in speculative geophysics.

Boston: Yeah—come on, geophysicists! [laughs] Why shouldn’t they get in the game? We’ve been doing it in astrobiology for a long time.

In fact, when I’ve asked my colleagues certain questions like, “Would we even get orogeny on a three Earth-mass planet?” They are like, “Um… We don’t know.” But you know what? I bet we have the equations to figure that out.

It starts with something as simple as that: in different or more extreme gravitational regimes, could you have mountains? Could you have caves? How could you calculate that? I don’t know the answer to that—but you have to ask it.

ESA astronauts take microbiological samples during a 2011 training mission in the caves of Sardinia; image courtesy of the ESA.

Twilley: You’re a member of NASA’s Planetary Protection Subcommittee. Could you talk a little about what that means? I’m curious whether the same sorts of planetary protection protocols we might use on other planets, like Mars, should also be applied to the Earth’s subsurface. How do we protect these deeper ecosystems? How do we protect deeper ecosystems on Mars, assuming there are any?

Boston: That’s a great question. We are working extremely hard to do that, actually.

Planetary protection is the idea that we must protect Earth from off-world contaminants. And, of course, vice versa: we don’t want to contaminate other planets—both for scientific reasons and, at least in my case, for ethical reasons—with biological material from Earth.

In other words, I think we owe it to our fellow bodies in the solar system to give them a chance to prove their biogenicity or not, before humans start casually shedding our skin cells or transporting microbes there.

That’s planetary protection, and it works both ways.

One thing I have used as a sales pitch in some of my proposals is the idea that we are attempting to become more and more noninvasive in our cave exploration, which is very hard to do. For example, we have pushed all of our methods in the direction of using miniscule quantities of sample. Most Earth scientists can just go out and collect huge chunks of rock. Most biologists do that, too. You grow E. coli in the lab and you harvest tons of it. But I have to take just a couple grams of material—on a lucky day—sometimes even just milligrams of material, with very sparse bio density in there. I have to work with that.

What this means is that the work we are doing also lends itself really well to developing methods that would be useful on extraterrestrial missions.

In fact, we are pushing in the direction of not sampling at all, if we can. We are trying to see what we can learn about something before we even poke it. So, in our terrestrial caving work, we are actually living the planetary protection protocol.

We are also working in tremendously sensitive wilderness areas and we are often privileged enough to be the only people to get in there. We want to minimize the potential contamination.

That said, of course, we are contaminant sources. We risk changing the environment we’re trying to study. We struggle with this. I struggle with it physically and methodologically. I struggle with it ethically. You don’t want to screw up your science and inadvertently test your own skin bugs.

I’d say this is one of those cases where it’s not unacceptable to have a nonzero risk—to use a double negative again. There are few things in life that I would say that about. Even in our ridiculous risk-averse culture, we understand that for most things, there is a nonzero risk of basically anything. There is a nonzero risk that we’ll be hit by a meteorite now, before we are even done with this interview. But it’s pretty unlikely.

In this case, I think it’s completely unacceptable to run much of a risk at all.

That said, the truth is that pathogens co-evolve with their hosts. Pathogenesis is a very delicately poised ecological relationship, much more so than predation. If you are made out of the same biochemistry I’m made of, the chances are good that I can probably eat you, assuming that I have the capability of doing that. But the chances that I, as a pathogen, could infect you are miniscule. So there are different degrees of danger.

There is also the alien effect, which is well known in microbiology. That is that there is a certain dose of microbes that you typically need to get in order for them to take hold, because they are coming into an area where there’s not much ecological space. They either have to be highly pre-adapted for whatever the environment is that they land in, or they have to be sufficiently numerous so that, when they do get introduced, they can actually get a toehold.

We don’t really understand some of the fine points of how that occurs. Maybe it’s quorum sensing. Maybe it’s because organisms don’t really exist as single strains at the microbial level and they really have to be in consortia—in communities—to take care of all of the functions of the whole community.

We have a very skewed view of microbiology, because our knowledge comes from a medical and pathogenesis history, where we focus on single strains. But nobody lives like that. There are no organisms that do that. The complexity of the communal nature of microorganisms may be responsible for the alien effect.

So, given all of that, do I think that we are likely to be able to contaminate Mars? Honestly, no. On the surface, no. Do I act as if we can? Yes—absolutely, because the stakes are too high.

Now, do I think we could contaminate the subsurface? Yes. You are out of the high ultraviolet light and out of the ionizing radiation zone. You would be in an environment much more likely to have liquid water, and much more likely to be in a thermal regime that was compatible with Earth life.

So you also have to ask what part of Mars you are worried about contaminating.

ESA teams perform bacterial sampling and examine a freshwater supply; top photo courtesy ESA–V. Crobu; bottom courtesy ESA/T. Peake.

Manaugh: There’s been some interesting research into the possibility of developing new pharmaceuticals from these subterranean biospheres—or even developing new industrial materials, like new adhesives. I’d love to know more about your research into speleo-pharmacology or speleo-antibiotics—drugs developed from underground microbes.

Boston: It’s just waiting to be exploited. The reasons that it has not yet been done have nothing to do with science and nothing to do with the tremendous potential of these ecosystems, and everything to do with the bizarre and not very healthy economics of the global drug industry. In fact, I just heard that someone I know is leaving the pharmaceutical industry, because he can’t stand it anymore, and he’s actually going in the direction of astrobiology.

Really, there is a de-emphasis on drug discovery today and more of an emphasis on drug packaging. It is entirely profit-driven motive, which is distasteful, I think, and extremely sad. I see a real niche here for someone who doesn’t want to become just a cog in a giant pharmaceutical company, someone who wants to do a small start-up and actually do drug discovery in an environment that is astonishingly promising.

It’s not my bag; I don’t want to develop drugs. But I see our organisms producing antibiotics all the time. When we grow them in culture, I can see where some of them are oozing stuff—pink stuff and yellow stuff and clear stuff. And you can see it in nature. If you go to a lava tube cave, here in New Mexico, you see they are doing it all the time.

A lot of these chemistry tests screen for mutagenic activity, chemogenic activity, and all of the other things that are indications of cancer-fighting drugs and so on, and we have orders of magnitude more hits from cave stuff than we do from soils. So where is everybody looking? In soils. Dudes! I’ve got whole ecosystems in one pool that are different from an ecosystem in another pool that are less than a hundred feet apart in Lechuguilla Cave! The variability—the non-homogeneity of the subsurface—vastly exceeds the surface, because it’s not well mixed.

ESA astronauts prepare their experiments and gear for a 2013 CAVES ("Cooperative Adventure for Valuing and Exercising human behaviour and performance Skills") mission in Sardinia; image courtesy ESA–V. Crobu

Twilley: In your TED talk, you actually say that the biodiversity in caves on Earth may well exceed the entire terrestrial biosphere.

Boston: Oh, yes—certainly the subsurface. There is a heck of a lot of real estate down there, when you add all those rock-fracture surface areas up. And each one of these little pockets is going off on its own evolutionary track. So the total diversity scales with that. It’s astonishing to me that speleo-bioprospecting hasn’t taken off already. I keep writing about it, because I can’t believe that there aren’t twenty-somethings out there who don’t want to go work for big pharma, who are fascinated by this potential for human use.

There is a young faculty member at the University of New Mexico in Albuquerque, whose graduate student is one of our friends and cavers, and they are starting to look at some of these. I’m like, “Go for it! I can supply you with endless cultures.”

Twilley: In your “Human Mission to Inner Space” experiment, you trialed several possible Martian cave habitat technologies in a one-week mission to a closed cave with a poisonous atmosphere in Arizona. As part of that, you looked into Martian agriculture, and grew what you called “flat crops.” What were they?

Boston: We grew great duckweed and waterfern. We made duckweed cookies. Gus made a rice and duckweed dish. It was quite tasty. [laughs] We actually fed two mice on it exclusively for a trial period, but although duckweed has more protein than soybeans, there weren’t enough carbohydrates to sustain them calorically.

But the duckweed idea was really just to prove a point. A great deal of NASA’s agricultural research has been devoted to trying to grow things for astronauts to make them happier on the long, outbound trips—which is very important. It is a very alien environment and I think people underestimate that. People who have not been in really difficult field circumstances have no apparent understanding of the profound impact of habitat on the human psyche and our ability to perform. Those of us who have lived in mock Mars habitats, or who have gone into places like caves, or even just people who have traveled a lot, outside of their comfort zone, know that. Your circumstances affect you.

One of the things we designed, for example, was a way to illuminate an interior subsurface space by projecting a light through fluid systems—because you’d do two things. You’d get photosynthetic activity of these crops, but you’d also get a significant amount of very soothing light into the interior space.

We had such a fabulous time doing that project. We just ran with the idea of: what you can do to make the space that a planet has provided for you into actual, livable space.

From Boston's presentation report on the Human Utilization of Subsurface Extraterrestrial Environments, NIAC Phase II study (PDF).

Twilley: Earlier on our Venue travels, we actually drove through Hanksville, Utah, where many of the Mars analog environment studies are done.

Boston: I’ve actually done two crews there. It’s incredibly effective, considering how low-fidelity it is.

Twilley: What makes it so effective?

Boston: Simple things are the most critical. The fact that you have to don a spacesuit and the incredible cumbersomeness of that—how it restricts your physical space in everything from how you turn your head to how your visual field is limited. Turning your head doesn’t work anymore, because you just look inside your helmet; your whole body has to turn, and it can feel very claustrophobic.

Then there are the gloves, where you’ve got your astronaut gloves on and you’re trying to manipulate the external environment without your normal dexterity. And there’s the cumbersomeness and, really, the psychological burden of having to simulate going through an airlock cycle. It’s tremendously effective. Being constrained with the same group of people, it is surprisingly easy to buy into the simulation. It’s not as if you don’t know you’re not on Mars, but it doesn’t take much to make a convincing simulation if you get those details right.

The Mars Desert Research Station, Hanksville, Utah; image courtesy of bandgirl807/Wikipedia.

I guess that’s what was really surprising to me, the first time I did it: how little it took to be transform your human experience and to really cause you to rethink what you have to do. Because everything is a gigantic pain in the butt. Everything you know is wrong. Everything you think in advance that you can cope with fails in the field. It is a humbling experience, and an antidote to hubris. I would like to take every engineer I know that works on space stuff—

Twilley: —and put them in Hanksville! [laughter]

Boston: Yes—seriously! I have sort of done that, by taking these loafer-wearing engineers—most of whom are not outdoorsy people in any way, who haunt the halls of MIT and have absorbed the universe as a built environment—out to something as simple as the lava tubes. I could not believe how hard it was for them. Lava tubes are not exactly rigorous caving. Most of these are walk-in, with only a little bit of scrambling, but you would have thought we’d just landed on Mars. It was amazing for some of them, how totally urban they are and how little experience they have of coping with a natural space. I was amazed.

I actually took a journalist out to a lava tube one time. I think this lady had never left her house before! There’s a little bit of a rigorous walk over the rocks—but it was as if she had never walked on anything that was not flat before.

From Venue's own visit to a lava tube outside Flagstaff, AZ.

It’s just amazing what one’s human experience does. This is why I think engineers should be forced to go out into nature and see if the systems they are designing can actually work. It’s one of the best ways for them to challenge their assumptions, and even to change the types of questions they might be asking in the first place.

(This interview was previously published on Venue).

Architecture-by-Bee and Other Animal Printheads

[Image: By John Becker].

For thousands of years, animal bodies have been used as living 3D printers—or sentient printheads, we might say—but the range of possible material outputs is set to change quite radically. In fact, bioengineering is rapidly making this idea—that spiders, silkworms, and honeybees, to name just a few, are already 3D printers—more than just a poetic metaphor.

Those creatures are organic examples of depositional manufacturing, and they have been domesticated and used throughout human history for specific creative ends, whether it's to produce something as mundane as honey or silk, or something far more outlandish, including automotive plastics, military armaments, and even concrete, as we'll see below.

Animal Printheads

Researchers in Singapore discovered several years ago, for example, that silkworms fed a chemically peculiar diet could produce colored silk, readymade for use in textiles, as if they are actually biological ink cartridges; and other examples—in which animal bodies have been temporarily tweaked or even specifically bred to produce new, economically useful materials on a semi-industrial scale—are not hard to come by.

As it happens, for example, using bees as 3D printers is quickly becoming something of an accepted artistic process and its deep incorporation into advanced manufacturing processes will not be far behind.

Perhaps the most widely seen recent exploration of the animal-as-3D-printer concept was done last year for, of all things, a publicity stunt by Dewar's, in which the company "3D printed" a bottle of Dewar's using nothing but specially shaped and cultivated beehives.

[Images: Courtesy of Dewar's, via designboom].

These pictures tell the story clearly enough: using a large glass bottle as a mold in which the bees could create new hives, the process then ended with the removal of the glass and the revealing of a complete, bottle-shaped, "3D-printed" hive.

As Dewar's joked, it was 3B-printed.

[Images: Courtesy of Dewar's, via designboom].

Or take the Silk Pavilion, another recent project you've undoubtedly already seen, in which researchers at MIT, led by architect Neri Oxman, 3D-printed a room-sized dome using carefully guided silkworms as living printheads.

[Image: Courtesy of MIT].

The Silk Pavilion was an architectural experiment in which the body of the silkworm, guided along a series of very specific paths, was "deployed as a biological printer in the creation of a secondary structure."

The primary structure, meanwhile—the pattern used by the silkworms as a kind of depositional substrate—was nothing more than a continuous thread wrapped around a metal scaffold like a labyrinth, seen in the image below.

[Image: Courtesy of MIT].

It was at this point in the process that a "swarm of 6,500 silkworms was positioned at the bottom rim of the scaffold spinning flat non-woven silk patches as they locally reinforced the gaps across CNC-deposited silk fibers." In other words, they infested the labyrinth and laid down architecture with their passing.

[Image: Courtesy of MIT].

The “CNSilk" method, as it was known, resulted in a gossamer, woven dome that looks more like a cloud than a building.

[Images: Courtesy of MIT].

What both of these examples demonstrate—despite the fact that one is a somewhat tongue-in-cheek media ploy by an alcohol company—is that animal bodies can, in fact, be guided, disciplined, or otherwise regulated to produce large-scale structures, from consumer objects to whole buildings.

After all, the very origins of architecture were a collaboration with animal bodies, and experiments like these only update those earliest constructions.

In both cases, however, the animals are simply depositing, or "printing," what they would normally (that is, naturally, in the absence of human augmentation) produce: silk and honey. Things get substantially more interesting, on the other hand, when we look at more exotic biological materials.

Bee Plastic

For half a decade or more, materials scientist Debbie Chachra at New England's Olin College of Engineering has been researching what's known as "bee plastic": a cellophane-like biopolymer produced by a species native to New England, called Colletes inaequalis.

These bees secrete tiny, cocoon-like structures in the soil—one such structure can be seen in the photo, below—using a special gland unique to its species. The resulting, non-fossil-fuel-based natural polyester not only resists biodegradation, it also survives the temperate extremes of New England, from the region's sweltering summers to its subzero winter storms.

[Image: Courtesy of Deb Chachra].

More intriguingly, however, the cellophane-like bee plastic "doesn't come from petroleum," Chachra explained to me for a 2011 end-of-year article in Wired UK. "The bees are pretty much just eating pollen and producing this plastic," she continued, "and we're trying to understand how they do it."

Bee plastic, Chachra justifiably speculates, could perhaps someday be used to manufacture everything from office supplies to car bumpers, acting as an oil-free alternative to the plastics we use today. In the process, it could perhaps even kickstart a homegrown bio-industry for New England, where the species already thrives, wherein the very idea of a factory needs to be fundamentally reimagined.

The most exciting architectural possibilities here come less from the bees themselves and more from the elaborate structures that would be required to house their activities; imagine a brand new BMW factory somewhere in the suburbs of Boston populated only by plastic-producing bees, and you get some sense of where industrial manufacturing might go in an alternate future. Not unlike Dewar's bee-printed bottle, then, augmented cousins of Chachra's plastic-producing bees could thus 3D-print whole car bodies, kitchen counters, architectural parts, and other everyday products.

But even this, of course, is a vision of animal-based manufacturing that relies on the already-existent excretions of living creatures. Could we—temporarily putting aside the ethical implications of this, simply to discuss the material possibilities—perhaps genetically modify bees, silkworms, spiders, and so on to produce substantially more robust biopolymers, something not just strong enough to resist biodegrading but that could be produced and used on an industrial scale?

Recall, for example, that the U.S Army, working with a Canadian firm called Nexia Biotechnologies, was successful in its attempt to genetically engineer a goat that would produce spider-silk proteins in its milk. Incredibly, those "Biosteel goats," as they were later known, were eventually housed in old ammunition bunkers on a New York State military base, as if they were living bioweapons that needed to be held in quarantine.

[Image: Biosteel goats summed-up in one simple equation (via)].

The ultimate goal of producing these goats was to generate an unbreakable super-fiber that could be used in battle gear, including "lightweight body armor made of artificial spider silk," and other military armaments; but others have speculated that entire bridges or other pieces of urban infrastructure could someday be woven by goats.

These possibilities become even more strange and promising when we move to materials like concrete.

Concrete Honey

As part of an ongoing collaborative project, NYC-based designer John Becker and I have been looking at the possibility of using bees that have been genetically modified to print concrete. We could call them architectural printheads.

[Image: By John Becker].

Initially inspired by a somewhat willful misreading of a project published under the title "Bees Make Concrete Honey," John and I began to imagine and illustrate a series of science-fictional scenarios in which a new urban bee species, called Apis caementicium—or cement bees—could be deployed throughout the city as a low-cost way to repair statues and fix architectural ornament, even to produce whole, free-standing structures, such as cathedrals.

[Image: By John Becker].

In a process not unlike that used for the Dewar's bottle, above, the bees would be given an initial form to work within. Then, buzzing away inside this mold or cast, and additively depositing the ingredients for bio-concrete on the walls, frames, or structures they've been attached to, the bees could 3D-print new architectural forms into existence.

This includes, for example, the iconic stone lions found outside the New York Public Library; they've been damaged by exposure and human contact, but can now be fixed from within by concrete bees. Think this as a kind of organic caulking.

[Image: By John Becker].

Yet tidy plots such as these invariably spin out of control and things don't quite go as planned.

Feral Printers

Predictably, these concrete bees eventually escape: first just a few here and there, but then an upstart colony takes hold elsewhere in the city. They breed, speciate, and expand.

Within a few years, as the bees reproduce and thrive, and as their increasingly far-flung colonies grow, people become aware of the scale of the problem: rogue 3D-printing bees have begun to infest the region.

[Image: By John Becker].

They print where they shouldn't print and, without the direction of their carefully made formwork and molds, what they produce often makes no sense.

They print on signs and phone poles; they take over parks and gardens where they print strange forms on flowers, sealing orchids and roses in masonry shells. Bizarre gardens of hardened geometry form on windowsills and ledges, deep in urban forests and along railways and roads.

[Image: By John Becker].

Tiny fragments of concrete can soon be seen atop plants and door frames, beneath cars and on chain-link fences, coiling up and consuming the sides of structures where they were never meant to be, like kudzu; and, of course, strange bee bodies are found now and again, these little concrete-laden corpses lying in the deep grass of backyards, on parking lots and rooftops.

[Image: By John Becker].

Their fallen bodies, augmented and extraordinary, thus dot the very city they've also beautified and improved—this place where they once printed church steeples and apartment ornament, where they fixed cracked statues, sidewalks, and walls.

Of course, other, more adventurous or simply disoriented bees make their way further, hitching inadvertent rides in the holds of planes and cargo ships, mistakenly joining other hives then shipped around the world.

The bees are soon found in Europe, China, and—for reasons never quite clear to materials scientists—throughout India, where, as in the sample image below, they can be seen adding unnecessary ornamentation to temples in Rajasthan. Swarming and uncountable, they busily speck the outside of the building with bulbous and tumid additions no architect would ever have planned.

[Image: By John Becker].

As the bees speciate yet further, and their concrete itself begins to mutate—in some cases, so hard it can only be removed by the toughest drills and demolition equipment, other times more like a slow-drying sandstone incapable of achieving any structure at all—this experiment in animal printheads, these living 3D printers producing architecture and industrial objects, comes to end.

A Bee Amidst The Machines

Most designers learn from the—in retrospect—obvious mistakes that led to these feral printers, returning to more easily controlled inorganic factories and industrial processes. But, even then, on quiet spring days, a tiny buzzing sound can occasionally be heard beneath someone's front porch, out in the suburban gardens somewhere, deep inside National Parks, and even inside huge machines, where whole automobile assembly lines come shuddering to a halt.

There, within the gears, just doing what it's used to doing—what we made it do—a tiny family of 3D-printing bees has taken root, leaving errant clumps of concrete wherever they alight.

(Thanks to John Becker for the fun. An earlier version of this post was previously published on Gizmodo).