[neilep (OP)]

Dearest Virologists,

(doesn't one work here ?  [])

Viruses are like....well nasty !..though they do look pretty !

look, here's one !



Don't ask me which one it is ....all I can tell ewe is that it's green with bobbly bits !

Viruses can only reproduce inside ewe or me or inside something else eh ?

So, how did the first virus come about ?...It had to be " born" inside a host yes ?...does that mean viruses are human/animal made (do plants get viruses ?)


whajafink ?



ta


Neil
Executive officer In Charge Of Asking This Question
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

[mike2niner4]

Hey,

Don't really know the answer but i do know plants get viruses as well. Such as the Pepper mild mottle virus.

[neilep (OP)]

Hey,

Don't really know the answer but i do know plants get viruses as well. Such as the Pepper mild mottle virus.

Thanks Chum,

so, even poor plants get viruses too !..damn those pesky virus thingys !!

[blakestyger]

Ewe might be amazed to hear that the largest biomass on Earth is made up of viral material; that you're very own genome is mostly bits of old retroviral sequence that doesn't do anything - I mean that in the nicest possible way, of course.

I don't know where viruses come from but it's safe to say they are ancient life forms. If you have an interest in viruses you may like to see this:

<Link since died>

Its format is an interview with an imaginary magazine but it's a piece of coursework really.

[lyner]

Hey, blakestyger
That was an excellent link. I couldn't put it down.

[blakestyger]

Thanks - glad you liked it.

[chris]

Somehow I missed this post the first time, so here I am, a decade later, answering the question! I hope @neilep you're not too frustrated by the wait. But look on the bright side, people have spent longer on hold on the phone trying to cancel their direct debit with Eon, HMRC or BT...

Viruses are obligate intracellular parasites. In plain English, they are infectious packets of genes that require a living cell to provide key functions that they lack so that they can replicate and increase their numbers.

Viruses come in many different shapes and sizes, both literally, and metaphorically. Some are absolutely tiny: particles of norovirus, which is one of the commonest causes of diarrhoea and vomiting, are just 30nm - 1/30,000th of a millimetre - across. Other viruses are enormous in comparison. The recently-discovered mamaviruses, pithoviruses and pandoraviruses are so large that there were initially mistaken for bacteria, which are usually orders of magnitude bigger than a virus.

This broad diversity, and the fact that viruses target every living entity on Earth including even other viruses (there are viruses that prey on viruses: these are called virophages), suggests that they have been around for a very long time and may even predate modern multicellular life itself.

One theory of the origin of viruses posits that they were initially a spin-off from the first cells. Genetic functions that had evolved to replicate themselves escaped the confines of their parent cell and became independent entities that nevertheless came home to roost in the cell to replicate but otherwise had little else in common.

Other hypotheses even regard some viruses as the origin of life on Earth. The giant viruses mentioned above (gyruses) contain such a broad repertoire of genes that cross all three of the main kingdoms of life, and also even include genes not seen in any living species, suggests that perhaps these entities gave rise to us all from the primordial soup.

The bottom line is that viruses contain an assemblage of genes that enable them to freeload off living cells, which they hijack by first fooling the cell into allowing them in, and then assimilating by using genetic tricks that can deactivate all but the most essential and useful cellular systems to enable the virus to grow rapidly, or they do the opposite and deactivate themselves so that they can lurk undetected within the genetic recesses of the cell, either by pretending to be a miniature chromosome that the cell ignores, or inserting themselves inside the host cell's own DNA. In both cases they end up immunologically "off grid".

But, next time you are sneezing into a hanky having fallen prey to another rhinovirus infection, you can take some solace from the fact that this is not a modern problem. Genetic analysis confirms that dinosaurs had herpes! More a case of T-sex than T-rex, perhaps...

[neilep (OP)]

Somehow I missed this post the first time, so here I am, a decade later, answering the question! I hope @neilep you're not too frustrated by the wait. But look on the bright side, people have spent longer on hold on the phone trying to cancel their direct debit with Eon, HMRC or BT...

Viruses are obligate intracellular parasites. In plain English, they are infectious packets of genes that require a living cell to provide key functions that they lack so that they can replicate and increase their numbers.

Viruses come in many different shapes and sizes, both literally, and metaphorically. Some are absolutely tiny: particles of norovirus, which is one of the commonest causes of diarrhoea and vomiting, are just 30nm - 1/30,000th of a millimetre - across. Other viruses are enormous in comparison. The recently-discovered mamaviruses, pithoviruses and pandoraviruses are so large that there were initially mistaken for bacteria, which are usually orders of magnitude bigger than a virus.

This broad diversity, and the fact that viruses target every living entity on Earth including even other viruses (there are viruses that prey on viruses: these are called virophages), suggests that they have been around for a very long time and may even predate modern multicellular life itself.

One theory of the origin of viruses posits that they were initially a spin-off from the first cells. Genetic functions that had evolved to replicate themselves escaped the confines of their parent cell and became independent entities that nevertheless came home to roost in the cell to replicate but otherwise had little else in common.

Other hypotheses even regard some viruses as the origin of life on Earth.The giant viruses mentioned above (gyruses) contain such a broad repertoire of genes that cross all three of the main kingdoms of life, and also even include genes not seen in any living species, suggests that perhaps these entities gave rise to us all from the primordial soup.

The bottom line is that viruses contain an assemblage of genes that enable them to freeload off living cells, which they hijack by first fooling the cell into allowing them in, and then assimilating by using genetic tricks that can deactivate all but the most essential and useful cellular systems to enable the virus to grow rapidly, or they do the opposite and deactivate themselves so that they can lurk undetected within the genetic recesses of the cell, either by pretending to be a miniature chromosome that the cell ignores, or inserting themselves inside the host cell's own DNA. In both cases they end up immunologically "off grid".

But, next time you are sneezing into a hanky having fallen prey to another rhinovirus infection, you can take some solace from the fact that this is not a modern problem. Genetic analysis confirms that dinosaurs had herpes! More a case of T-sex than T-rex, perhaps...

I've literally worn a hole in the table tapping my fingers the last decade for this. Refreshing the page every thirty seconds !!

Thank ewe @chris. Absolutely fascinating and I was pondering the same all those years ago regarding how Mr and Mrs Virus may have done the deed and become mummy and daddy to life here.

 Brilliant answer. Thank ewe so much !!

Now to get that manicure after tapping my fingers for so long !!

T-sex....lol .....Norty dino !!

[chris]

Thank ewe @neilep  for holding. Your question is important to us and we will answer it shortly...

[neilep (OP)]

Ha ha lool 

Thank ewe @neilep  for holding. Your question is important to us and we will answer it shortly...

[Paul.D]

It is very difficult to trace the origin of viruses due to the fact that they do not leave fossils. They can utilise many different tricks into order to infect an organism and replicate many copies of themselves within the cells it has invaded. There is also evidence that some viruses can incorporate their own genes into the cells that they have infected. This means that in order to study their ancestry requires untangling it from the history of their host and other organisms. Another thing which makes this extremely difficult is the fact that it doesn't just infect humans but can infect practically any organism, which can range from bacteria to horses; seaweed to people. Do to all these obstacles the origins of most viruses may remain forever obscure.

[CliffordK]

With the huge diversity of viruses, including DNA viruses and RNA viruses, it is quite possible that they evolved independently multiple times. 

Bacteria have a couple of methods for directly sharing DNA including direct environmental DNA sampling, as well as transferring looped DNA called Plasmids through a couple of methods. 

It is quite possible that some plasmids evolved into infectious baceriophages (viruses) by adding a protein shell, and better ways to inject genetic material.