Why do Viruses exist?

[Joe the Liberal]

Well this may sound like a stupid question but I'm curious so I will ask anyway. With this Swine Flu that's broken out it got me thinking of why do viruses even exist? They don't do anything but harm, so why do they even exist?

[AllentownJake]

1. Why do I exist?

[nolabels]

53. Are you sure you do? Maybe possibly, you are just a figment of your own imagination

I never have put too much faith in believing anything, especially such strange ideas that put me here at this present time typing this response about existence :shrug:

[RedCappedBandit]

2. Why do humans exist? We don't do anything but harm.

[AllentownJake]

5. Plastic

At least that's what was George Carlin's theory.

[dflprincess]

6. And the fact we do so much harm may explain why viruses exist

- something has to stop us. :evilgrin:

[HeresyLives]

3. Why not?

In fact, viruses may actually be the important life on the planet, and we exist solely as a transportation system for them. ;)

[Joe the Liberal]

7. That's one way of looking at it lol. n/t

[HeresyLives]

18. Well, we always have such big egos.

And there may be no reason whatever to do so. :rofl:

[girl gone mad]

27. Viruses aren't "life"

They aren't alive.

[customerserviceguy]

29. I must disagree

They fulfill the most basic tenet of "alive" -- they reproduce. They are not mere chemical reactions.

[HeresyLives]

31. Viruses are indeed alive.

They reproduce and they evolve.

[sam sarrha]

48. they form mineral like crystals when purified

[Odin2005]

54. the definition of "alive" is extremely fuzzy.

Viruses reproduce, but they do not have their own metabolism (they parasitize the metabolism and physiology of their host in order to reproduce the genetic material and capsid) and thus are not "alive" according to the strict definition of an organism as an "autocatalytic chemical system that maintains internal homeostasis and undergoes Darwinian evolution."

[Teaser]

4. What do you mean they don't do anything but harm?

They do great for viruses. They reproduce their asses all over the places.

That's the only reason.

For anything.


ENJOY!

[Profprileasn]

47. Exactly

they survive long enough to multiply and pass on their genes.

[MrModerate]

8. Because they can. No, seriously . . .

They exploit a billion different niches with a very lightweight genetic toolset. Life is just astounding in the ways it will propogate itself and extract what it needs from the environment.

Evolution in action . . .

[Avalux]

9. Who knows? They were on this planet long before humans.

They are certainly odd structures; not even complete cells.

[HughMoran]

10. Why do bed-bugs exist?

Any/every combination of molecules that are relatively stable and can combine and reproduce in the human body (random chance) can and will exist at some point in history.

[eShirl]

11. Unintelligent Design?

[nebenaube]

12. to facilitate evolution...

What, do you think the mutations in DNA from background radiation is sufficient to advance the evolution of species? Not to mention it proves that even pseudo-life-forms evolve.

[napoleon_in_rags]

50. That's the most interesting answer on this whole page.

It lead me to this in reading about it:
http://en.wikipedia.org/wiki/Transduction_(genetics)
I had no idea that even happened. Amazing.

[Odin2005]

56. That's why the fear about GMOs is funny. This stuff happens all the time, though at a low level.

IIRC 14% of our DNA is derived from silenced retroviruses (viruses like HIV that stick themselves into ones own genes).

[Tumbulu]

51. That is what I learned in grad school many years ago. (nt)

[frogcycle]

13. why do tapeworms exist?

why does bubonic plague exist?

why does the moon exist?

why does george w. bush exist?

[Joe the Liberal]

14. I think I can answer the last 1........

"why does george w. bush exist?"

To make peoples lives miserable? would be my guess. :rofl:

[Boojatta]

15. "why does the moon exist?"

Why do you hate heavenly bodies upon which American astronauts have walked?
;)

[frogcycle]

24. who said anything about hate?

why does navel lint exist?

[NOW tense]

16. To thin the herd. n/t

[virgogal]

17. Just another form of life.

[BlooInBloo]

19. Evolution. For recent developments, read "Guns, Germs and Steel".

[customerserviceguy]

30. Read it last year, truly one of the best books I've found

Recommended reading for everyone!

[BlooInBloo]

32. It's definitely excellent.

[Juche]

33. There is also a documentary

For those of us too lazy to read.

http://video.google.com/videoplay?docid=-4008293090480628280

[Odin2005]

57. Yep. IIRC ALL flu is ultimately Bird Flu.

Influenza originally jumped to us from domesticated chickens 1000s of years ago.

[Juche]

20. Because they can

The purpose of life is to not die. Anything that is good at not dying is still alive, everything that sucked at it has gone extinct. Viruses are good at not dying.

Life in a nutshell. The only purpose and goal viruses have is to keep existing. That is the only purpose of all life.

[Joe the Liberal]

25. Yes but aren't virsuses dead?

or considered "non-living", if the purpose of life is to not die then how can the purpose of a virus be to not die if it's not even alive?

[Juche]

28. Life was technically dead when it first began

Life likely either began as a replicating molecule (a crystal, RNA, nobody knows) or it began as a redundant molecular reaction. Replicator first vs. metabolism first. So life began as something that we would consider dead, and only evolved into something that fits the definition of 'life' later.

A redundant metabolic cycle or a replicating crystal is not considered life, but that may be what life evolved from.

[Imperialism Inc.]

42. That is up for debate. Much to the chagrin of creationists everywhere there

isn't a simple demarcation line between life and non-life. Viruses reproduce but they don't do some of the other things that life forms do like metabolize. Is a virus alive? Depends on which scientist you ask.

[BlooInBloo]

55. It's mostly a semantics issue, not unlike whether or not Pluto is a "planet".

[Retrograde]

21. They're here because they're here

One of the hardest things for me to get my head around is that evolution has no ultimate purpose: it just happens. An organism mutates into existence, it manages to reproduce itself a little more efficiently than its competitors, and it takes off. No Great Plan or Grand Design, just the luck of the gene shuffle. Viruses are here for the same reason hagfish and sea squirts and slime molds and hummingbirds and oxalis and kelp and most everything else is: they reproduce well.

[Juche]

26. There may not be a purpose, but there may be a predictable result to evolution

If you read Robert Wright, Ray Kurzweil or David Sloan Wilson one thing they talk about is how cooperation tends to trump competition and as a result life forms that form larger, more complex forms that are better at manipulating their environment tend to win out. On a long enough timeline it may be inevitable to end up with a technologically advanced species that eventually has the technology to liberate itself from the shackles of biology, like we are on the cusp of doing and will accomplish in the 21st century. Once the conditions for life start it may be almost inevitable that sooner or later a life form will evolve that has the technological prowess to escape the limits of their home planet and biological programming and starts to recreate the universe in its own image.

The point is that more complex, more ordered forms of life tend to have survival advantages over less organized, less complex ones. Some molecular reactions evolved into basic prokaryotes and won out. Some prokaryotes evolved into eukaryotes. Some eukaryotes evolved into multicellular organisms. Some multicellular organisms evolved into social organisms. Some (ok, one) social organisms evolved the ability to make technology. Each jump, although rare, gave massive survival advantages.

In Sloan's book he talks about how in the entire history of insects, only about 15 times have insects made the jump from solitary to social insects (wasps, bees, hornets, termites, ants, cockroaches, etc). But becoming social insects provided such a massive evolutionary advantage with regards to predator defense, food finding, survival, reproduction, etc that descendents of those 15 jumps make up 50% of all insect biomass on earth.

[Odin2005]

59. I ADORE David Sloan Wilson!

I recomend everyone read his book "Darwin for everybody"

I'm a Ray Kurzweil fan, too! :)

[Juche]

62. Yay, another Sloan Wilson fan

Evolution for everyone is one of my favorite books and it is the kind of book you have to read 3 times to really grasp what it tells you. I am wanting to get Darwin's cathedral soon and check that out.

Its too bad this is the internet and not real life, we could hang out. I don't know of many Sloan and Kurzweil fans who like to think about issues as pertinent and deep as the connectedness of technology, evolution and human behavior. The singularity and evolutionary psychology are two of my favorite subjects to learn about.

Robert Wright is again, another good one but he is more pessimistic than Wilson. With Wilson you walk away thinking evolution isn't so bad (Wilson talks about how you can control environment to produce altruistic and prosocial behaviors and how prosocial behaviors are almost guaranteed sooner or later since prosocial groups have advantages over selfish groups). Wright has sort of a more pessimistic outlook on evolution, but he is interesting nonetheless.

[targetpractice]

43. That was an epiphany for me...

My world was never the same after I "got my head around" that concept by reading Richard Dawkins' "The Selfish Gene."

Dawkins goes on to claim that we shouldn't focus on the reproduction/survival o organisms or species... but instead, it's the "gene" that's important. People, organisms, virii, species, etc. are survival machines for particular genes that remain chemically unchanged for millions of years.

BTW, Dawkins invented the term "meme" in that book as a way to describe a thought or concept that reproduces itself outside of the biological framework of reproduction.

[Warpy]

22. There's a small body of evidence

that suggests some viruses are responsible for evolutionary changes.

There are viruses that attack bacteria.

Non lethal viruses might make us sick, but they also strengthen our immune systems.

I have a sneaking suspicion that we wouldn't have a very nice planet without viruses.

[Deja Q]

23. Why do mosquitoes, leeches, and Microsoft exist?

:evilgrin:

:hide:

[Fozzledick]

60. To spread viruses?

:yoiks:

[Vidar]

34. Just another way to thin the herd.

[Posteritatis]

35. Evolution doesn't care at all about reasons for a species/strain to exist (nt)

[elocs]

36. Humans are a virus:

http://www.youtube.com/watch?v=Hn6WZh17BF4

[targetpractice]

41. Language is a Virus....

http://www.youtube.com/watch?v=DZkjoXyexKk

[MrPerson]

37. Its not a virus, its a feature.

[realisticphish]

44. haha nt

[targetpractice]

38. They replicate, therefore they do.

The better things are at replicating themselves, the more there will be.

There is no motivation or purpose behind it.

[Lucian]

39. It's God's punishment for the Fall of Man.

Duh. :crazy:

[Joe the Revelator]

40. To control the population

[realisticphish]

45. Nothing needs a purpose

they are one of the earliest forms of life (yes, life) and fill their niche very well. Sharks haven't evolved that much because there haven't been changes in the environmental pressures that necessitate evolution (or, rather, that only creatures that happen to evolve survive)

And as to "harm," they aren't harming anything, as far as they are concerned. They replicate. That's all they do :shrug: It's not their fault that the replication kills us...

[Duer 157099]

46. Think of them as the bees of the genetic world

Aside from the fact, as someone stated above, that the simplest answer is that they exist because they can, they also provide a mechanism for genes to move around, especially interspecies, which, let's face it, isn't quite so easy in the natural sense.

There's no judgement about it, not saying that it's good that such things happen, just that it's advantageous to some lifeforms.

It is because it can be.

[sam sarrha]

49. if you think they are weird.. check out 'Prions'

[Odin2005]

52. Viruses have a wide variety of origins.

Some RNA viruses are thought to go back to the very beginnings of life on Earth, the so-called "RNA World", lineages of little bits of parasitic RNA that lived on as life in general moved on to DNA, proteins, and true cells, among these ancients are the Retroviruses, such as like HIV. Other viruses seem to have ultimately come from highly reduced bacteria. And still more (probably the vast majority of viruses) are derived from mutated bits of DNA and RNA that went rogue.

Basically they are molecular-scale parasites and have the same origin as all other parasites, evolution.

[elleng]

58. Because they CAN.

.

[hyphenate]

61. Depends on a multitude of reasons

Up front, and most significant, is that it's a form of evolution. Only the "strong" survive, and over the years, it's been true that those who manage to gain some immunity to both virii and bacteria survive to go on while those who are susceptible are not going to pass their genes on.

If you're a creationist, forget it. i have no coherent, logical reason why they exist at all. (The fundies, not the virii)

If you think about deaths from virii and bacteria throughout history, significance of different plagues and epidemics has shown that most of them have been blamed on the wrath of god in some fashion. Nowadays, we know better, but there are still outbreaks in third world nations that can be avoided with more education and modern medicine. How many of the historical epidemics could have been avoided with more modern medical knowledge is likely a high number.

[Occam Bandage]

63. Teleological thinking is misguided. nt

[MineralMan]

64. The Good Lord Made Them All...

Even virii gots to eat.

[pnutbutr]

65. balance of nature

When populations become too large there are ways that nature works to restore balance. Viruses are one of the ways nature does this.

[dysfunctional press]

66. i doubt that the viruses see what they do as "harm"...

kind of like human beings in that respect.