1. Since evolution is a continuous process, with life forms evolving and adapting, with the most versatile surviving and eventually coming out on top, then what evolutionary purpose does a virus serve?

Efilism 101: Evolution is imperfect.

Not everything needs to have what you'd call an "evolutionary purpose", as though everything that exists is justified by its nature. There are some things that are completely unjustified by their nature, and viruses are indeed one of them. You could ask the same of a wide variety of things.

Why do we breathe out of the same hole that we shove food/liquid in?

If the purpose of pain is to kick ourselves into gear in crisis situations, why can't we tell our bodies, "Okay, I get it, I need to go to the hospital, stop hurting me now?"

Why do we have to be given incentives to do things in the first place?

All of these things are what you might call "unintelligent design", and, truthfully, viruses are a big part of it, too. There's no rhyme or reason for it--it's simply just another one of nature's many flaws. Just because evolution's purpose is to allow our species to survive in our environment doesn't mean that it's very good at it.

2. Survival instinct.

Can anybody here, give any sort of guess as to where it came from? Again, if we're going with the rule set of evolution, it's a trial and error process over a very long stretch of time. It's theorized that we have such a fear of things like spiders because it was an evolutionary development because traditionally, a fair number of spiders can be deadly.

But, from day one, if there was no survival instinct, there wouldn't be much in the way of complex celluar life on the planet at all. But, logically speaking anyway, from day one, how could you possibly have any sort of life form with a pre-established need to survive?

Whether it be eating, duplicating, or anything else?

Ehhh, I don't find these type of questions really worth asking, to be honest. I'm not terribly concerned about the "where" or the "how", and neither should you. What should really strike you as more important is the "why", and the "why" happens to be a lot easier. Because if we didn't have the survival instinct, we wouldn't care to survive. Of course.

But no, I don't think anyone really knows where that came from. I don't think we should really waste our time with such questions, though. There's nothing we could really glean from such information anyway.

A virus that inhibits itself from further transmission and reproduction by damaging its host too seriously is a failure and it dies out as soon as its means of reproduction do. A virus does not exist to harm anyone, a virus exists to propagate itself. So to say that one that one is "better" simply because it's more lethal is strange, because it's the exact opposite.

a good point, though it speaks nothing of a virus's evolutionary purpose (beyond the propagation of itself)

i think he was asking more in terms of the grand scheme--which, i don't believe there is one
but yeah, that's great that you picked up on that at least

Isn't propagation itself enough of an explanation of the purpose of something's functions? In the end don't all adaptations, things that make organisms more survivable or versatile or intelligent or so on, simply provide better means of ensuring continued reproduction? In many cases there are ones that lead away from that end, but with time only the adaptations that move towards reproduction survive.

No, because I could just ask, "Why do we need to survive"?

Quote from: eggsalad on June 24, 2015, 02:32:24 PM

Isn't propagation itself enough of an explanation of the purpose of something's functions? In the end don't all adaptations, things that make organisms more survivable or versatile or intelligent or so on, simply provide better means of ensuring continued reproduction? In many cases there are ones that lead away from that end, but with time only the adaptations that move towards reproduction survive.

No, because I could just ask, "Why do we need to survive"?

We as humans can ask that question and are able to decide for ourselves, which isn't necessarily a good thing for our survival as a race, at which point evolution would cease for us. I don't really get what "evolutionary purpose" even means at that point.

1. Viruses aren't considered to be alive, It's directive is as it stands, multiply and spread.

2.Where self preservation kicked in who knows. It probably branched from the necessity to multiply from early microbes.

Quote from: Saleem on June 25, 2015, 04:57:19 AM

1. Viruses aren't considered to be alive

I thought they kind of straddled the boundary? Isn't it something that biologists are always fighting over?

A virus is just some DNA wrapped inside a protein shell. On it's own it's pretty much an inanimate object.

When it collides with a cell and the protein shell happens to be compatible with the cell's membrane, it gets absorbed by the cell and the ribosomes will begin making copies of it. Without regulation to control the copying, it will keep making copies until the cell fills up and explodes, ejecting millions on new viruses that will repeat the process if another cell comes into contact.

I don't know what sandtrap means by "evolutionary purpose" but a virus will continue to exist as long as it can keep infecting new hosts. They are really good at it do to the sheer number of copies that get made, since it ensures that the ribosomes will make many typos that will alter the structure, creating a lot of new mutants. From simple probability it is almost guaranteed that some of these mutants will be both functional and distinct enough that they will not be detected by new antibodies or would even work on cells of a new species.

If a virus or any other infecting agent is good enough at finding new hosts, then it really has no reason to keep the host alive even if it may be more "efficient." Evolution only favors efficiency in situations where the alternative means death, something that viruses easily circumvent. It follows the same rules as supply and demand economics, if supply is high (it is easy for a virus to find a new host) while demand is low (a virus only needs one new host every few days to survive), a single host has little value.