Except, instead of using their onboard oxygen supply to carry blood, they react it with whatever organic molecule they diffuse in to. Because I expect that synthetic catalysts will be much more efficient than nature (because they are rationally optimized and constructed of materials not found in nature, such as diamondroid and/or rare earth components) I expect that they will consume biomass at a rate limited only by diffusion. They do not need to consume all biomass on the planet - the heat generated by their activities will set forests on fire, cause land animals to "spontaneously" combust, set fires to buildings, vehicles, etc.
Some of the bots may be destroyed by the fires they themselves cause, I cannot model that.
How to counter? The most straightforward way is probably that these devices would have weak points. You might be able to produce a synthetic molecule preferentially binds to the catalytic portion of these bots and jams them. I'm not real certain that would do any real good, however. It might let you save a human patient, but not the biosphere.
The way to survive in the short term in a bunker. These bots can't eat any material that cannot be combusted, and a broader rule is that no nanobot of any design can operate for long on material that can't be reacted to release free energy. So, ordinary concrete, thick walls of corrosion resistant metals, etc would provide a good defense against most or all nanobots.
On the bright side of things, the same technology used to make the robots could in principle allow survivors to live in self-contained bunkers, since a relatively small nano-factory could replace the many square miles of infrastructure we need in order to produce essential technologies today.
Today's post, Raised in Technophilia was originally published on 17 September 2008. A summary (taken from the LW wiki):
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This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was My Best and Worst Mistake, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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