[Avery Andrews 940827.0849]
(Rick Marken (940825.1440))
>This definition of ESV seems to leave open the possibility that such
>variables may NOT actually be crucial for survival (hence, they are not what
>we call "intrinsic" variables; if an intrisic variable is not kept under
>control the organism dies). Your definition makes me wonder why anyone would
>care whether organisms can control ESVs or not. It also makes me wonder what
>you mean by the following:
I don't quite understand this. ESV's aren't intrinsic variables because
they aren't necessarily sensed, or influencable, by the organism.
A tadpole cannot influence the maximum depth of water in the ditch it
lives in; a kangaroo can't make it rain. Actually I myself am not 100%
sure why people care about ESVs - it's just a term I made up to try to
get at what I think is on the minds of a lot of people these days.
From a practical point of view, I think that, say herpetologists working
on conservation problems involving animal behavior really do see things
in terms of ESVs and CEVs/perceptions. E.g. the baby turtles at Heron
Island tend to wander into the resort instead of heading out to see
'because they get confused by the lights' according to a guy I heard
talking about them at the local herp society a few weeks ago. The ESV
is direction of travel, and its desired value is out to sea, one of the
perceptions is something involving lights, and the new ones at the
resort have damaged the linkage between CEV and ESV. I doubt whether this
terminology would be useful in tackling this conservation problem, but
I think it is not too far off as an abstract description of how
the actual herpos I've been listening to would think about out.
More later, maybe
Avery.Andrews@anu.edu.au