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Why did I choose something as mind-bogglingly common as sulfur for a bottleneck element? I was trying to make a point about carrying capacity in ecological systems: life is greedy, and if you give it long enough, anything can become limiting. Besides, any primitive microbe from a hydrothermal environment is likely to have a serious sulfur-dependency problem. (The specialists in the audience will notice that I carefully avoided making ßehemoth an obligate sulfur-reducer; I actually envision the little mother's metabolism as being more akin to that of the giant sulfide-consuming microbes reported by Schulz et al. [18].)
Bottom line, most of ßehemoth's traits have real-world precedents. Whether evolution could actually pack all those attributes into a package 250 nanometers across is a whole different issue, of course. Still. Look at all the stuff that fits into Batman's utility belt.
The idea of behavior-modification technology is old stuff in fiction; Burgess' A Clockwork Orange is an obvious example. In Maelstrom I've taken a stab at rediscovering that wheel by explicitly tweaking genes and neurochemistry.
As far as I know, the existence of the "Minsky receptors" that Alice Jovellanos mentions has yet to be confirmed. Something like them, however, must be seated in the frontal cortex where human conscience and morality (such as they are) reside [19, 20]. At the very least, certain types of frontal-lobe damage have a tendency to turn good God-fearing folk into sociopaths.
I imagine that Ken Lubin's murder reflex is wired into the neural circuitry described by R. Davidson et al. [21] The conceit of using tweaked parasite genes to program such behaviour came to me when I was teaching an undergraduate course in animal ecology. The parasites mentioned in Maelstrom are real, and have a lot of company [22, 23]. One fly-eating fungus hijacks its victim's nervous system just before killing it, forcing it to fly to an upside-down perch and orient its abdomen at an optimum angle for spore disperal. An ant-fluke called Dicrocoelium takes control of its host each night, riding it to the top of a convenient stalk of grass and freezing it there until morning in hopes that some other hapless host will eat it. And yes, Toxoplasma really does cause rats to lose their fear of cats (and in some cases, actually to be attracted to the smell of cat urine). It is also found in about half the members of our species. This stuff is straight out of The Puppet Masters, folks. There's even a substantial amount of evidence to suggest that sex itself evolved primarily as a countermeasure against parasite attacks [24].
First, the Wilderness. The Internet is already more like a wildlife habitat than you might expect. Internet «storms» were first described in 1997 [25], which makes them old news: nowadays you can link to "weather maps" of Internet meteorology [26], updated several times daily. (Once again, my far-flung futuristic foresight has proven wonderfully adept at predicting the past. The last time was when Starfish predicted submarine ecotours to deep-sea rifts within fifty years, only to have such tours advertised in the real world by 1999.)
Those of you who have taken an undergraduate physiology course may remember the power law. It's a surface-area-to-volume relationship that governs living systems from whole food webs right down to the capillaries of shrews—essentially a pattern typical of self-organizing systems (i.e., biological) systems. As it turns out, the World Wide Web itself appears to be evolving in concordance with this law [27]. Something to think about…
Second, the Wildlife. These days it's hardly necessary to cite references on the subject of "artificial life": a web search on the phrase (or on "cellular automata") will demonstrate how massively the field has exploded over the past ten years. That subset of e-life which goes by the name «Anemone» is admittedly a bit more speculative, and based upon two premises. The first is that simple systems, in aggregate, display emergent behaviors beyond the capability of their individual parts. This is pretty much self-evident within a body—who'd deny that a brain is smarter than an individual neuron, for example? — but the principal extends even to aggregations of completely unco
A related premise is that lineages with genetically-determined behavior would be able to pass a Turing test if they evolved fast enough. This won't be hard to swallow for anyone familiar with how sophisticated such behaviour can be; we do, after all, live in a world where ants practice animal husbandry, birds follow orthodome routes to navigate halfway around the world, and honeybees convey sophisticated travel instructions by wiggling their asses at each other. Skeptics might want to read any of E. O. Wilson's books on sociobiology, or an old Scientific American article by John Holland [30]. It's way out of date, but it clearly conveys the principals behind genetic algorithms.
Finally, anyone who treats the phrase "group selection" as an obscenity (I admit they're right, most of the time) might first want to check out D.S. Wilson's review article of the subject in Skeptic [31]
Research on the construction of thinking meat has proceeded apace since Starfish came out. Recent research is thumbnailed in "Neurons and silicon get intimate", by Robert "no-not-that-Robert" Service [32]. More conventional neural nets are literally in the driver's seat: Carnegie Mellon's ALVINN program (which I mentioned briefly in the references to Starfish) has now moved moved onto the highway, where neural nets have autonomously taken ninety-mile jaunts on public highways, at speeds up to 70mph. They learned to drive by watching people at the same task. It took them less than five minutes.
We still can’t be sure exactly what neural nets actually learn when we train them. Paradigm cock-ups of the sort that made my "head cheeses" betray their masters have happened in real life. One infamous military neural net taught itself to distinguish between various ambient light conditions, while all along its humans thought they were teaching it to recognize tanks [33].
Back in Starfish I cited Roger Penrose's quantum-consciousness theory to justify the rudimentary psi-powers of the rifters. Here in Maelstrom Lubin uses the same trick to interrogate Achilles Desjardins. In the interest of full disclosure I should admit that Penrose's theory has come under serious attack from a guy called Tegmark [34]: the quantum-mind afficionados have rallied [35], but things may be looking a bit iffier on the quantum-consciousness front these days. What can you do.
18 Schulz, H.N., et al. 1999. Dense populations of a giant sulfur bacterium in Namibian shelf sediments. Science 284: 493–495.
19 Macmillan, M. 2000. An Odd Kind of Fame Stories: of Phineas Gage. MIT Press, Cambridge, MA, 576pp.
20 Anderson, S.W. et al. 1999. Impairment of social and moral behavior related to early damage in human prefrontal cortex. Nature Neuroscience 2: 1032–1037.
21 Davidson, R.J., et al. 2000. Dysfunction in the neural circuitry of emotion regulation—a possible prelude to violence. Science 289: 591–594.
22 Zimmer, C. August 2000. Do parasites rule the world? Discover: 80–85.
23 Zimmer, C. 2000. Parasites make Scaredy-rats foolhardy. Science 289: 525–527.
24 John Re
25 Huberman, B.A., and R.M. Lukose. 1997. Social Dilemmas and Internet Congestion. Science 277: 535–537.
26 Matrix-net's Internet Weather Report, at http://www.mids.org/weather/.
27 Barabasi, A.-L. et al. 1999. Internet: Diameter of the World-Wide Web. Nature 401: 130–131.
28 Parrish, J.K., and Edelstein-Keshet, L. 1999. Complexity, Pattern, and Evolutionary Trade-offs in Animal Aggregation. Science 284: 99-101.
29 Koch, C., and G. Laurent. 1999. Complexity and the nervous system. Science 284: 96–98.
30 Holland, J. H. 1992. Genetic algorithms. Scientific American, 267(1): 66–72.
31 Wilson, D.S. 2000. Nonzero and nonsense: group selection, nonzerosumness, and the Human Gaia Hypothesis. Skeptic 8(1): 84–89.
32 Service, R. 1999. Neurons and silicon get intimate. Science 284: 578–579.
33 Episode four of the PBS video series "The Machine that Changed the World": Go to http://www.otterbein.edu/home/fac/dvdjstck/CSC100/CSC100TMTCTW.htm* * *TM for farther information.
34 Tegmark, M. 2000. The importance of quantum decoherence in brain processes. Physical Review E61: 4194–4206.
35 Quantum computation in the brain? Decoherence and biological feasibility", abstract of a talk given at the 2000 Tucson Conference by the University of Arizona's Center for Consciousness Studies (available online at http://www.consciousness.arizona.edu/hameroff/decoherence.html* * *Abstract)