As preface, and to muddle the waters further, the orginal quip about a non terrestrial origin for BD was more to the idea that the BD is just a kind of terraforming ,removing the pesky dominant lifeform from a world to be utilized.
Secondly finding a bug, viral or otherwise that can infect and kill so a large portion of our phenotypicly varient species is nil.We stick our nose everywhere, come into contact with agents our immune system has not met before, lose individuals but our immune spectrum becomes stronger for it.
In any case, once more into the breach!
In certain conditions, given a limited number of practical options, evolution has some "typical" courses. When two species meet and start affecting each other, the result can often be guessed by imagining the relevant optimality models.
Practical options?So the species think about it?
When viruses of similar strands (can be targeted with the same antibodies) compete for infecting host cells, and host immune systems counteradapt to defend against them, the optimality model tends to favour quick infection and distribution with limited harm to the host organism.
Again viruses do not move under their own power, they are not little drills equipped with jetpacks.In the above example the sucessful (but potentially suicidal) course would be to produce as many copies of the viron as possible, breakout of the cell thus killing it and out compete by numbers the milquetoast version of itself.The fate of the host is irrelavent as long as the virus can infect new ones.Humans have been encountering hydrophobia for millenia but we have yet to see a kinder/gentler version thereof.
<font color=yellow>I will now commit the offense of personalizing evolution. It has no person. It obtains a direction only in meaningful interaction between different evolving agents. What I am really trying to do is describing a good evolutionary strategy from the point of view of a virus.</font color=yellow>
Get quickly to the next host. If you wait, others will reach the next host before you. Killing your host harms your ability to spread.
But in this case killing the host in wholesale lots thereby collapsing their infrastruture would prevent them from using quarantine and other means to stop you.
Making him/her cough and sneeze makes spreading easier. If you can maintain infection while the host lives, you are a very efficient virus. But counting on this is a short-sighted strategy. If the host dies or the immune system eliminates you, fast spreading will have ensured that your copies will live on.
Good enough
Therefore upon contacting a new species, try to avoid becoming the black death.
Again, they don't think, plan ,or get e-mail for that matter.
Instead strive to become the common cold. Your first epidemic may fail, becoming the black death. You may drive the species extinct, and die with your host population. But if you (and your host) survive the first outbreak, it is imperative that you become milder and maximize your population. Killing the host population does not maximize your population.
True enough if we are talking about the natural reservior but for a dead end host it does not matter if it kills none, one ,or all.
Beside it appears to be a weapon of sorts and as such you would wan't it to burn through the target population as quickly as possible and then disappear completely so as not to threaten you or your plans.
Sorry for imprecise wording. That was exactly what I meant. There should be adults out there whom the virus does not touch.
No need to apologize at any level whatsoever, this is way to much fun.
My assumption was that the virus was engineered from a natural variety. Some people must have had antibodies against this natural variety. Upon contacting virus antigens, their bodies could have immediately activated all defense mechanisms, thus fighting off the infection
And this doesn't even address the people who (a minium of 1:20,000 ) because of congenital, pathological,or accidental misadventure lack the wherewithal to reach puberty!
Not that simple. With an age-specific virus, some cells would have the receptor, others would not. If you belong to the age group in between, the virus can kill only some of your cells. While it infects you, you will have a chance to develop immunity.
Again ,it kills too quick.Or to put it another way if the "few"cells its killing comprise the vagal pressure sensors in the aorta the host is still going to be taking a dirt nap.
It all depends on how the immune system responds. If the immune system is "experieced" enough to fight, but not strong enough to destroy, a balance is likely. The host lives and the virus lives. Hiding in DNA and sleeping, then reactivating and checking if the immune system is still there. Then hiding again. Indefinitely.
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-----Ok .. they don,t have drills, jet packs or tiny sensor arrays either. They have no way of "determining" the patency of the immune system.But to be fair the causitive agent for chicken pox exibits a behavior like this , being locked in the host cells and only freed in the subject suffers trauma, but it does not free itself for a lookround.
To sum it up, that virus is unlikely to have disappeared while people still walk the Earth. Nature is not black and white. There are plenty of grey areas. <font color=yellow>Viruses do not live to kill. Killing is their side effect. They live to live.</font color=yellow></font color=yellow><hr></blockquote>
But this does not preclude behavior that on the face of it is suicidal (lemmings attempting to migrate across a land bridge that isn't there anymore comes to mind)
As an aside, and not to bepresumptuous, where but the works of JMS would you find a didactic such as this ,albeit more than a little retentive?