People don't understand evolution...

[shadesofmauve]

I'm listening to TED talks at work, currently Paul Ewald on creating gentler germs, by creating conditions that select for lower virulence.

Interesting stuff, and very clearly put -- if a parasite requires a living host for transmission, strains that quickly kill the host will die off. So, reducing opportunities for non-person-to-person transmition will create an evolutionary disadvantage for virulent strains. Cool!

Then I see this in the comments:
"But this is not domestication, this is out-competition. In other words, the organism did not ADAPT to be less of a severe pathogen, severe pathogens did not have any further advantage over milder forms."*

They forget to mention that severe pathogens actually have a disadvantage, because they incapacitate their host before the host can transmit infection.

The commenter is saying that what happens is NOT evolution...but it is, even by their own explanation. Evolution is not individual adaptation; evolution happens over populations. If the virulent strain in a viral population is "out-competed" to extinction, then the population has become less virulent.

On the happy hand, real discussion takes place in the comments! Woo!

Comments

[fenmere.livejournal.com]

Actually, Stephen J. Gould did a pretty good job of pointing out that there is no strong evidence that evolution is even progressive.

In other words, organisms only compete when there aren't enough resources for them. There are often long periods of times when there's plenty of space and resources for a given ecosystem, and during those times a wide variety of species can thrive. And even then, when times tighten, it doesn't always tighten in the same way, killing off only those organisms that don't fit that particular puzzle.

So, in short, evolution is "survival of the fit enough."