The danger of lemurs destroying the Earth has been vastly overinflated.
That’s exactly what you want us to think, isn’t it?
Because they could be made out of materials that natural organisms can’t eat for one. They would also likely be more efficient, due to being rationally designed. And for another, the simple fact that they are a wholly new creation makes them dangerous; evolved creatures tend not to deal well with incursions by species that evolved outside the local ecosystem. Something that isn’t even our kind of life is going to be even harder to deal with.
On the contrary, the fact that natural organisms have been shaped by evolution makes them less likely to be as efficient as possible at reproducing themselves. First, because an evolved organism is a collection of kludges, a Rube Goldberg machine accumulated over millions of years. And second because reproducing as efficiently as possible isn’t typically the best reproductive strategy, given how doing so tends to destroy your own food sources and result in a later population crash.
Well, there is that danger from subatomic particles. Strangelet - Wikipedia
a particle called a “strangelet” might convert normal matter into more strangelets on contact.
Also you may be interested in reading about ice 9, seeing no one has brought it up. Cat's Cradle - Wikipedia
The danger of making them out of specific rare materials, or to operate only under specific conditions. Is that these are replicators - almost certainly imperfect replicators. They’ll evolve.
Not unless you design them with the ability. Unless specifically designed to be capable of evolution, things created by a human-style design process don’t evolve when replicated imperfectly; they just break. The only reason that the ability to evolve is so universal to organic life is because it all comes from ancestors that could evolve.
But what if the nanobot was also a bending unit?
Well duh, we’d placate it with liquor and nanohookerbots.
Yeah but that was hardly one species completely sweeping the earth overnight. It was the collective effect of many species of photosynthesizing cyanobacteria operating over at least 200 million years.
Human -designed things (physical ones, at least) don’t self-replicate at the moment, so there isn’t a good example to point out - but it’s simply untrue to say that they ‘Just break’ and stop functioning - some things, especially complex ones, malfunction and produce unintended output when they break.
Something as small as a nanobot would be subject to random modification from stray cosmic rays, etc. It’s not so much that we would need or choose to design a imperfect replicator, it’s more that we are probably incapable of designing a completely perfect one - thus, evolution may well happen anyway, regardless of our design, or wishes.
You’re kind of arguing both ways, here. I’ll grant that it’s quite possible a designed nanobot is more effective than a given bacteria; there is indeed nothing magical about natural selection. But that ‘nothing magical’ particularly applies to the second part of your statement: reproducing efficiently is always the best strategy and what natural selection will get as close to as possible. A bacteria that’s in a resource-rich environment and holds off on reproducing will get out-competed by ones that reproduce as fast and efficiently as possible. Sure, if the resources run out the population will crash, but the remaining population will be drawn from the quick reproducers. And of course, if resources are limited, the population is going to be small in the long run anyway, so it really makes no difference whether it’s quickly after a big population , or a little later with no big spike in population.
And of course, the real world is full of examples of populations that grow quickly consuming a limited resource and then crash.
The vast majority of time, when a self-replicator replicates imperfectly, it breaks. This is just as true of the already-existing kind as of the ones we could make. All it takes for evolution is for, once in a very great while, one to replicate imperfectly and not break.
Nanobots or, more probably microbots on a similar scale to bacteria would be only part of the action. They could be manufactured by larger machines that are resistant to evolution thanks to error-checking. The small-scale devices could be as incapable of self-replication as red blood cells, but just as indispensable for the growth and self-replication of the entire system.
Evolution is not inevitable in a correctly designed self-replicating system - the data management (artificial genetics) could be designed to check for errors using ECC and to eliminate them. In theory devices could be built that do not mutate for billions of years.
Robert Bradbury devised a scheme to use self-replicating systems to destroy the whole Earth, not just its biosphere.
First you have to destroy Mercury, using the power of the Sun and self-replicating machines that strip the surface of that small planet and convert it into orbiting solar-power collectors. If fully dismantled Mercury could intercept a large fraction of the Sun’s output. These collectors would transmit power to a second set of self-replicating systems, which do the same thing to Earth. Dismantling Mercury first isn’t entirely necessary, but the extra power it makes available would speed things up considerably.
I suppose dismantling the Moon first would help as well, seeing as it is handy.
Although this is not perhaps the best use of the earth and its resources, it might be just the ticket in a colony solar system where there are no inhabitable planets; a family of inhospitable planets could be dismantled and turned into artificial habitats or a matrioshka brain.
Agreed, design can minimise or provide resistance to mutation.
But DT’s assertion that mutation would have to be designed-in is not correct.
Instead of evolution nanobots could be designed to combine to make more variable macrobots. However, any way it’s done, the bots wouldn’t be much more effective than humans at changing the earth. They’ll run out of resources just as quickly as we do. If they want to destroy mankind killing humans by infection will be the simplest route.
cough cough
Depends what you mean by destroy.
Infections can wipe out species that are already on the brink of extinction. But a widely-dispersed species with 7 billion individuals, not so much. That’s just based on natural variation, leave aside that humans will apply their technology to fight it, alter their behaviour and so on.
But no doubt a virulent infectious disease could kill huge numbers and freeze the progress of civilization for decades.
Nanobots that can survive in virtually any environment on Earth, can utilize an incredible variety of energy sources, and can self-replicate already exist. They’re called bacteria and archaea, and they effectively have taken over the world already. Actually, it was never really ours to begin with. Prokaryotes make up about half or more of the biomass on the planet. The 100 trillion or so bacteria living on and inside you outnumber your own cells by about 10 or 20 to 1.
Considering that bacteria and archaea are: A) rabidly evolving; B) Incredibly diverse metabolically; C) capable of extremely rapid self-replication in the right conditions and D) have been around for about 3 billion years and still haven’t reduced the Earth to “goo,” I’d say we’re probably pretty safe from a man-made “gray-goo” scenario.
Well I meant infection by bots. They should be very effective at killing a human and moving on to the next poor sucker. Biological diseases tend to evolve towards a symbiotic state, though perhaps one could be designed for the purpose of extermination.