I’m at a conference at Biosphere 2, the large ecological research facility in the Arizona desert that was originally launched as an attempt at creating a sealed, self-contained ecosystem.
It’s a surreal place — a collection of glass pyramids and domes housing miniature rain forests, deserts, an “ocean,” and a few other biomes — that’s now used for more “normal” research and education. I’m here not to join some a futuristic commune (at least not yet), but rather as a participant in a fascinating conference organized by Research Corporation called “Molecules Come to Life” — basically, it’s getting a lot of people who are interested in complex living systems together to discuss big questions, think of new research directions, and launch new projects. It’s a fascinating and very impressive group that’s here. Interestingly, a huge fraction are physicists, either physicists in physics departments (like me) or people trained as physicists who are now in systems biology, bioengineering, microbiology, etc., departments.
Do the conference topic and the venue have anything to do with one another? Explicitly, no. But in an indirect sense, both touch on issues of scale. A key issue in the study of all sorts of complex systems is how to relate phenomena across different extents of space and time. How can we connect the properties of molecules to the operation of a biological circuit? A circuit to a cell? A cell to an organism? Are there general principles — like those that tie the individually chaotic behaviors of atoms in a gas into robust many-particle properties like pressure and density — that lead to a deeper understanding? Would a piece of a complex system have the same behavior as the whole, or are collective properties scale-dependent?
The initial goal with Biosphere 2 was that these small-scale ecosystems under glass could function sustainably. This failed quite badly (at least at first — see Wikipedia for more details). As we learned on an excellent tour this afternoon, nearly all animals in the enclosure died, the food grown was so minimal that everyone was hungry all the time, and oxygen levels dropped from about 20% to 14% (at which point oxygen had to be pumped in). Walking around, the issue that kept coming to mind was: what is the scale of an ecosystem? Biosphere 2 is really not very big — it’s a few football fields in total area. Are the webs of interaction that can exist in an area this size sufficient to mimic a “real” rainforest, savannah, or other environment? Are they large enough to be stable, and not fluctuate wildly?
Perhaps these questions couldn’t have been answered without building the structure and trying the experiment. (Or perhaps they could.) It would be great to talk to the people behind the project — they were commune dwellers, not scientists — and see what thoughts, assessments, dreams, and predictions went into the planning of this impressive, but odd, place.
Some more photos:
The Eighteenth Elephant 
Has anyone sampled the microbes growing in those crazy domes?
I don’t know, but I doubt it. During the actual biosphere “mission,” they seem to have not thought much about microbes, and were surprised that so many in the soil sucked out their oxygen. There are now experiments on, for example, “rainforest” growth with lots of plants but no intentional cultivation of insects or other animals, which suggest that they’re not thinking much about microbes. There are also some experiments on soil generation from rock, which probably do involve microbes. The place is run by U of Arizona now, so I imagine that most of the experiments involve faculty there. It would be interesting to find out more!