Question: how did viruses come about?

Jordan Kirby answered on 6 Mar 2019: last edited 6 Mar 2019 8:33 am

Oh boy! So this is a topic that has been going on for a very long time.
.
So first off lets talk about what a virus is as its sort of important to understand why its a tough question.
.
So viruses are DNA surrounded by a protein shell (usually) and are all parasitic pathogens they rely entirely on their target host organism to do all the work and then reap all the benefits (kinda how if you were asked by your teacher to work as a group to do an assignment but one person did nothing but sign his name at the end of the paper ☺).
Their DNA does nothing but code for:
-Make new virus shell proteins (things that protect the DNA
-Make more of virus DNA
-The creation of other things to help the virus hijack the cell
.
The cell once hijacked does nothing but make new viruses until it eventually ruptures releasing all the new viruses to infect neighboring cells where the process begins again.
.
So viruses are quite unlike anything else on the planet as the dont repoduce (in the classical sense), they dont need food or have any organelles(microbe organs) and are completely reliant on other organisms for repoduction… So where did somthing so strange come from?
.
One theory is that these viruses were once a type of parasitic bacteria (which still exist today) that infected other cells. the theory is that since they lived in the bigger cells this bacteria didnt need to use as much of their own DNA to make things to survive (why bother when it could just use the hosts? Thats a big waste of energy and time to the bacteria!).
.
As a result over generations of not using these genes they were lost from the DNA (sort of like how muscles waste away in humans if you dont use them for really long periods of time) untill there was nothing left but a very bare bones lifeform whose only function is to: infect and repoduce
.
This is only one of the theories (and it does have criticism against it) but it is the easiest one to explain. All current theories have problems with them but modern virologists are still looking for the answer.
.
Whew sorry that was such a long post! But it was quite a hard question!
.
If you want to discuss anymore about any of this let me know in the comments and ill try to reply ☺