There is a species of parasite that infects ants, making them climb blades of grass so they are eaten by wandering bovines.
The cow was the target all along, not the ant.
The cow was the target all along, not the ant.
The parasites did their thing just fine for each individual organism. But that one random one that happened to cross wires in just the right way ended up doing orders of magnitude better. A rare occurrence, but very advantageous once it happens.
My theory is the parasite community for that species can survive other ways just fine, but has stumbled across a scenario that serendipidously gives it an extra boost at the change of reproducing.
I would imagine that most species that benefit from these complex interactions tend to have left-over backups for survival and reproduction. When species over-adapt to specific scenarios, it seems likely they'd become to susceptible extinction or their populations would be periodically thinned out.
That's one guess.
Berkeley's Understanding Evolution website has a nice overview of all the mechanisms of evolution. http://evolution.berkeley.edu/evolibrary/article/evo_14
I think it was Peeps.
http://www.ted.com/talks/dan_dennett_on_dangerous_memes?lang...