While most life on Earth is powered by chemical energy captured from solar radiation, deep in our seas there are entire ecologies powered by volcanism – specifically the hot water issuing from hydrothermal vents. Hot mineral-rich water supports a food chain based on chemosynthetic bacteria and archaea; it extends upwards in complexity through giant tube worms, clams, limpets and shrimp. These animals live miles further down than sunlight ever reaches, in an extreme of pressure and frigid temperatures that would kill any surface life in short order.
In recent years planetary astronomers have come to believe that beneath the icy surfaces of some of our gas-giant moons there are dark oceans of liquid water. Tidal forces acting on the moons power volcanism; Europa, in particular (the smallest of the four “Galilean” moons of Jupiter) is suspected of having its own hydrothermal vents. Exobiologists think it is relatively likely that life has evolved around them.
James Cambias’s A Darkling Sea (Tor) transplants the Europa scenario to Iluvatar, a moon in a solar system roughly half way between future Earth and the homeworld of aliens called the Sholen who are attempting to limit human interstellar expansion. A peace treaty with the Sholen constrains human scientists living in a seafloor habitat beneath the ice. They chafe to make contact with the intelligent arthropods at the top of Iluvatar’s foor chain, but are forbidden from contaminating their culture.
After a human scientist attempting to spy on the Ilmatar is captured and dissected by Iluvatarans who do not realize he is a sophont like themselves, a Sholen mission shuts down the base and orders the humans to evacuate. Some humans, refusing, flee into the lightless ocean and must make allies of the Iluvatarans to survive. When the Sholen’s clumsy attempts at forcing the issue kill some of the mission crew, the survivors vow to strike back.
Cambias imagines a detailed and convincing ecology for Iluvatar. The natives have plausible psychologies given their evolutionary history (the way Cambias develops the operation and limits of the sonar that is the only distant sense of these eyeless beings is impressive). The gritty details of life in a cramped, smelly human dive habitat are also well handled. Even the villains of the piece are not mere cardboard; the Sholen have their own internal factional problems, and become dangerous not because the are strong but because they are divided, afraid, and dwindling.
Overall, this is a tense, well-constructed SF novel of first contact, done in the classic Campbellian style and lit up with the sense of discovery that such works ought to have. It could have been written by Hal Clement or Arthur C. Clarke if either were still alive. It works excellently on that level, even if you don’t notice that the author has embedded in it a sly parable.
I won’t spoil the fun by laying it all out for you. But the viewpoint character’s last name is “Freeman”, and the repressive eco-pietism of the Sholen echoes the attitudes of some humans in our present day. The second half of the book, without ever tub-thumping about it, delivers a satire of various human political delusions. Even the Sholen social pattern of achieving consensus by bonobo-like sexual bonding carries mordantly funny symbolic freight once you realize what it’s a comment on.
All in all, highly recommended. This is much the best first SF novel I’ve read in the last few years, and leads me to expect good craftsmanship from Cambias in the future.