Are Viruses the same as Lot's Wife?

My 5-pound, 800 page, $200 biology textbook gives scant explanation to exactly how viruses differ from single-celled life. A few simple rules appear:

1. Viruses do not eat.
2. Viruses do not undergo binary fission (which all bacteria do).

It seems that until the very moment a virus encounters the cell wall of a target bacterium, it does nothing. It just sits there; its molecular and atomic structure unchanged from the moment it was 'born.' It doesn't eat, it doesn't starve, it doesn't breathe, it doesn't poop, it doesn't move. At this 'non-activated' state, a virus is indistinguishable from a very complex crystal of clay. But boy, when it makes contact with a target bacterium, it wreaks total havoc. It slyly and ingeniously commands the bacteria's DNA to make 200 copies of the virus and then kill itself.

Slyly? Ingeniously? How could an inanimate clay crystal be sly and ingenious? 

Easy. The virus (once in the cell wall), snips the bacteria's chromosomal DNA and inserts a bit of 'pirate code' into the bacterial DNA.* The bacterial DNA dutifully follows the pirated instruction sequence, one command at a time, until it's too late to stop. Upon completing the inserted pirate code, the bacteria DNA instructs itself to commit suicide, but not before making 200 or so copies of the invading virus. The cell walls explode (by command from the pirate code) and the 200 viruses fly free to continue the cycle.

Why Do Bacteria Eat?

Bacteria reproduce by splitting in half. Let's say a very simple bacteria (E. coli) contains 1 trillion atoms, when it splits each one contains 500 billion. If they split, 250 billion. And if they split, then 125 billion. In a few hours of splitting you run out of atoms! To correct this deficiency, bacteria eat things, ie. they import stuff ('food') into their cell walls to replace what was lost by splitting in two. Do bacteria eat to reproduce or reproduce because they eat? It doesn't really matter -- except they do -- and viruses don't.

Why Don't Viruses Attack Each Other? 

Think of two naked guys trying to steal each others' clothes.

Complexity from Simplicity vs. Simplicity from Complexity:

Bacteria generate complexity from simplicity (their 'food' is either sunshine and CO2 or heat + hydrogen sulfide). They create enormous complexity from the simplest raw materials. Viruses create simplicity from complexity. They attack bacteria and 'trick' the bacteria's DNA to commit suicide and produce a few hundred virus 'objects' + cellular rubble.

But Isn't This A Distinction Without A Difference?

As in, doesn't a human, eating a deer, turn a 'live deer' into just a bunch of meat and cells? Hasn't the deer been reduced from complexity to simplicity?

Good question, which is why the term 'parasite' is not very useful at any level of life. All life (except chlorophyll algae and plants) are to some extent 'parasites' (except if you call trees 'parasitic' upon sunlight). However, viruses create a very large and fundamental distinction. Viruses are not just that guy who didn't put his $10 into the check at the restaurant -- they are the guy who stole your wallet and all your money and then ate you. Viruses are nasty at an exponential level:

They make you willingly commit suicide with your own gun. 

But don't Angler fish use deception to the extreme, like tricking a little fish to thinking its fleshly lure is a worm? 

Good point. Snapping turtles do that too (with their tongues). But viruses take sensory deception to a 1,000-fold level. To understand this level-change, it's important to switch to computer language. The exact operation viruses perform on bacteria is like a computer virus inserting a 20-line piece of code into your computer's OS which says, "erase hard drive, then continue at line 2145." This is much different from a little fish drawn to near an Angler fishes' lure. This is more like an enzyme in the fishes' brain telling it to swim as fast as it can into a rock. The difference is important. A little fish fooled by an Angler fish's lure is still behaving normally -- a fish whose enzymes start turning its brains into a discombobulated pile of slop is not. But that is exactly what viruses do to the 'brain' of the bacteria -- the pirate DNA tells the bacterial DNA to turn itself into a pile of slop -- and it faithfully does it. And just before the bacterial DNA turns itself into slop, the inserted viral DNA code says, "On the way out, can you make a few hundred copies of me?"

Why Haven't Viruses Completely Destroyed All Life?

Good question. A true and competent generalist virus could (or should) be able to invade all living cells and trick their DNA into making copies of the virus and destroying themselves. They have tried ... Lord they have tried (just ask influenza in 1919). A plausible answer might be if we compare viruses to cowbirds, which never make nests but put their eggs in other birds' nests. Well ... if cowbirds won, there would not be any nests to put their eggs in and they would go extinct. Similarly, a "Viral Earth" would quickly grind to a halt since there would be no DNA left for the viruses to attack.

Are Viruses Better Described as Inorganic Crystals?

I favor this simply because viruses do not eat and do not reproduce. In the absence of viruses, bacteria would prosper quite happily for billions of years. In the absence of bacteria (or somatic cells), viruses would immediately go extinct. Rather than being life, viruses might be called adjuncts to life. But there is a clear distinction between viruses and true mineral molecules (like clay). Clay minerals will exist on a planet if there was or was never life. Viruses cannot eat clay -- they can't and don't eat anything. Without more complex DNA to pirate and subvert, viruses cannot exist.

But Don't Viruses Mutate and Evolve Much Like Life?

Correct. This is a key distinguisher between viruses and super-exotic clay crystals. Viruses contain DNA and they do mutate in the same fashion as life (incorrect copying + natural selection = evolution). We know this because influenza viruses can 'outfox' cell defenses almost as soon a new rampart is thrown upward. A working definition of a virus could be:

Virus (n.): A very small, non-heterotrophic, non-reproductive form of DNA and protein which follows Darwinian rules of mutation and selection pressure. 

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* Computer viruses re-write tiny sections of a computer's Operating System (OS) but leave 99.999 percent of the OS intact. A computer virus can be just a few lines of code; a computer OS comprises millions of lines of code. Without an OS, a computer virus has nothing to 'act upon.' Before bacteria, what did viruses have to 'act upon'? Think of a computer virus specifically written for a Commodore VIC-20 computer (c. 1986). Its 'code' might be still floating around in 2017, but what can it act upon?