Every building starts with a strong foundation — pouring concrete into a hole, constructing on top of it. But according to Martyn Dade-Robertson, the buildings on Mars won’t follow that formula, instead relying on colonies of genetically-engineered bacteria to be our de facto architects.
Dade-Robertson — professor of architectural design at Newcastle University — might seem crazy, but he’s onto something: Humans have always been playing catch-up to the construction genius of microbes. The plaque on your teeth is a structure built by bacteria, and we all know how sturdy and resistant it is against intruders. The planet’s youngest fossils are structures built by microbial colonies, called stromatolites. Even our most modern construction techniques rely on the labor of much simpler organisms: Cement is derived from calcium carbonate produced by living things like corals and mollusks — without them, we’d have no concrete, no cities. “Civilization is literally built on the fossils of sea creatures,” writes Dade-Robertson and colleagues in the Journal of the British Interplanetary Society.
So why not cut out the middlemen? Could we inject bacteria directly into the soil, and have it consolidate the soil into a sort of concrete, in response to the pressure from the house sitting above? Maybe. “From our work we know that there are a number of genes (over 100) whose regulation is changed as they come under pressure,” Dade-Robertson tells Inverse by email. “These genes are controlled by genetic switches so we have been looking for genetic switches which can be turned on or off. We can then use these genetic switches to turn on other genes which, for example, would synthesize materials — inducing calcium carbonate formation, for example.”
This isn’t science fiction. Already, a company called BioMason is making bricks cured by bacteria rather than heat. The process produces no carbon dioxide emissions — and the energy savings are enormous. Only the fossil fuel industry is responsible for more greenhouse gas emissions than the construction industry, worldwide. Another group out of Newcastle University has engineered BacillaFilla — a strain of bacteria that can live in a dormant state in concrete, awakening in the presence of cracks to spur the structure to repair itself.
Here on Earth, these technologies could be game-changers. On Mars, they might be our only option.
Transporting construction materials to build colonies on Mars is inefficient, estimated to cost about $50,000 per pound, and lacking (to the best of our knowledge) the fossilized remains of sea creatures, the ingredients for cement won’t be naturally available.
But bacteria isn’t heavy, and under the right environmental conditions, they can be willing conspirators in the construction of a new world. Dade-Robertson admits his bioengineered foundations are still a ways away from reality here on Earth, let alone in extraterrestrial space. There are technical challenges to overcome: his test-case bacteria, E. coli, wouldn’t much like a soil environment, so that will have to be swapped out. Then there’s getting it to produce the right sort of material in the right quantity at the right pressure.
Of course, there will be political, legal, and ethical complications, too. “Do people want genetically engineered microorganisms in their environment?” he asks. “Will governments legislate for it? These are questions that are at the forefront of our mind.” It’s certainly illegal, at least for the time being, to seed Mars with alien life forms from Earth.
Maybe in 20 years we’ll see some working form of bioengineered foundations for Earth-bound homes, Dade-Robertson says. These wouldn’t just save energy, they could actually be carbon-negative, since the production of calcium carbonate sequesters carbon dioxide.
The amazing thing about imagining how we might build on Mars is how it expands our minds in terms of the possibilities here on Earth. In the Journal of the British Interplanetary Society, Dade-Robertson and his coauthors point out that the point is to consider the future in a greater scope: “Ultimately, considering the challenge of new types of material and construction techniques is not only of practical use to the future colonizers of Mars, but also encourages us to think in new ways about the colonization of our own planet.”