Viruses: Life in the machine
An opening figure of my virus chapter shows how biological viruses parallel the behavior of computer viruses. Both kinds of entity infect a host system to propagate their own information, which contains the instructions to spread, infect, and spread again.
Are viruses alive? Biologists have long argued they are not, largely because isolated virus particles are inert, lacking metabolism. But who says life needs metabolism? They use the host cell’s metabolism, as do intracellular bacteria. And giant viruses such as Mimivirus, herpes, and pox viruses probably evolved from cells.
If biological viruses are alive, why not viruses in silico? If life evolved once out of the carbon soup, could it arise again in the machine?
Of course science fiction has long proposed various forms of silicon alien life, such as the Star Trek Horta’s eggs. But an ecosystem evolving out of a machine was not the place they had in mind.
A fascinating approach is to ask: If PC virus “life” has already evolved in the machine, does it show any of the same strategies as those used by living viruses? Let’s look at some ways that computer viruses work.
–PC viruses can be “Fast infectors” versus “Slow infectors.” Fast infectors infect as many files as possible–like Ebola virus, infecting every kind of tissue. On the other hand, slow infectors only infect files some of the time, or under certain situations. They turn out to be surprisingly effective at propagating. Similarly, herpes viruses are famous for lying low in the body; many kinds rarely affect the carrier at all. Nearly all of us carry undetected herpesviruses.
–PC viruses have ways to avoid detection by the “immune system” of anti-virus software. For example they kill the anti-virus functions (like HIV virus kills human T cells). Or the PC viruses hide within unused parts of a file (like human viruses that persist deep within cells).
–PC viruses can avoid detection by changing their code with each infection. Again, biological viruses do something similar, by allowing rapid mutations in certain genes. HIV virus replication can have an error rate as high as ten percent.
–The best defense against PC viruses is said to be “genetic diversity” of the host population (need I say more).
Some argue that because PC viruses are human-made, they don’t “count” as natural life. However, do we really know this? Could PC viruses arise spontaneously?
I’m sure some of you know more about the PC angle on this. Are viruses just the beginning; are more advanced forms of life likely to arise in the machine?