I'm a lot of a fan of Neal Stephenson's writing - he is among the most creative and innovative of modern SF writers. And 'Seveneves' is no exception as it tells the story of man's survival after the moon, inexplicably, blows up.
As ever with Stephenson, the writing is dense reflecting how much he's researched the ideas presented. Indeed, for non-physicists wanting to get their heads round the science and maths of orbits, the book is fantastic. But if your head doesn't want to get round Lagrange points and orbital decay the story still carries you along as a few thousand intrepid folk struggle to create a means of survival in space. And Stephenson knows his audience:
“We're not hunter-gatherers anymore. We're all living like patients in the intensive care unit of a hospital. What keeps us alive isn't bravery, or athleticism, or any of those other skills that were valuable in a caveman society. It's our ability to master complex technological skills. It is our ability to be nerds. We need to breed nerds.”
So up there in space (and, as a sideline, in caves under Alaska too) the human survivors have to eat. Indeed, it's the lack of food that does for one section of the space-dwellers, turning them into cannibals. The mention of how this started is a beautifully snarky reference to the culture of blogging and social media:
“Tav started it,” Aïda said. “He ate his own leg. Soft cannibalism, he called it. Legs are of no use in space. He blogged it. Then it went viral.”
The main source of food Stephenson gives us up in space is algae grown hydroponically in the little spaceships (delightfully named 'arklets'). And this is fine except that it's rather limiting. It's true that algae - as plants - have the additional advantage of helping with the atmosphere but it's a lot harder to get the necessary nutrients from this source than from another option - fungi. Yet, for some reason, this option isn't even considered even though the intensive production of fungi as meat substitutes is a well established science:
Mycoprotein is made in 40 metre high fermenters which run continuously for five weeks at a time.
The fermenter is sterilised and filled with a water and glucose solution. Then a batch of fusarium venenatum, the fungi at the heart of Mycoprotein, is introduced.
Once the organism has started to grow a continuous feed of nutrients, including potassium, magnesium and phosphate as well as trace elements, are added to the solution. The pH balance, temperature, nutrient concentration and oxygen are all constantly adjusted in order to achieve the optimum growth rate.
The organism and nutrients combine to form Mycoprotein solids and these are removed continuously from the fermenter after an average residence time of five to six hours. Once removed the Mycoprotein is heated to 65°C to breakdown the nucleic acid. Water is then removed in centrifuges, leaving the Mycoprotein looking rather like pastry dough.
If you were really setting up to survive in space entirely 'off-grid', I'd expect someone to suggest the role of fungi in making that possible. There's little about the process described above that couldn't be replicated off the planet. And for all you mushroom haters - you'd get used to it!
The next consideration - admittedly one Stephenson doesn't set out in scientific detail - is how to 're-terraform' the earth after it's surface had been scorched for four thousand years. Here, again the role of fungi (and to be fair those algae) is significant:
Mushrooms have been around for tens of millions of years and their activities are indispensable for the operation of the biosphere. Through their relationships with plants and animals, mushrooms are essential for forest and grassland ecology, climate control and atmospheric chemistry, water purification, and the maintenance of biodiversity. This first point, about the ecological significance of mushrooms, is obvious, yet the 16,000 described species of mushroom-forming fungi are members of the most poorly understood kingdom of life. The second point requires a dash of lateral thinking. Because humans evolved in ecosystems dependent upon mushrooms there would be no us without mushrooms. And no matter how superior we feel, humans remain dependent upon the continual activity of these fungi. The relationship isn’t reciprocal: without us there would definitely be mushrooms.
So, if you're going to create a human-friendly environment on a planet, the starting point has to be fungi because without those fungi it's not a human-friendly environment.
None of this distracts from the book. As James Lovegrove in the FT puts it:
Seveneves is a superhuman achievement, dense, eloquent, exhaustive, exhilarating, powerful, utterly readable, and ultimately uplifting. Stephenson imagines the worst that can happen, and insists that we can make the best of it. It’s the end of the world as we know it, and he feels fine.
I just think it would have been even better with mushrooms.