parasites tweaking reference signals?

[From Bruce Nevin (2007.06.27.1035 EDT)]

Sorry I haven't had time to read much less join in the culture
discussion.

The transitions from simpler to more complex organisms have been an
abiding interest of mine, with culture at the macroscopic end of the
spectrum (to our knowledge) and the question "What's in it for the
cell?" in the other direction. This is the question of different orders
of organisms that have a constitutive relation to one another. For
example, by controlling its cellular inputs in such a manner that its
behavior constitutes functioning as a nerve cell, the cell participates
(with its diverse fellow cells) in a more stable environment.

More generally, there is the evolutionary sequence culminating in those
constitive relationships:

  predator/pathogen -> parasite -> symbiote -> integral
constituent

Reported here in yesterday's NYT is some very intriguing information
about the parasite-host relationship.

Seems unlikely that a parasite adjusts e.g. the rat's reference value
for proximity to cats. Boldness in the face of any hazard is more likely
looking to the observer like boldness with cats. Interference with
control is a possibility, but this seems more specific, and we expect
reorganization to have diverse results in different individuals. And
consider the cat lady hypothesis at the end.

  /BN