Happy Herps

[Avery Andrews 950322]

One group of people who seem to have a practical grasp of the nature of
living control systems are herpetologists. It is a commonplace of
reptile husbandry, for example, that a good reptile cage should have
a temperature-gradient: the happy herp will wander around occupying
whatever position has the temperature it wants to be at. If it huddles
in one place, that's either the warmest spot in a too-cold cage, or
the coolest in a too-hot.

I heard an interesting variant of this last night, from someone whose
keeping a Perentie, which is a big desert monitor. Perenties hibernate
for six months of the year, & it's important that they be at the right
temperature: too cold, & they'll die; too warm, & they'll metabolize
too fast & starve, & with the cold (by Aussie standards) winters here
there's also the change that they'll come out and freeze to death.
Most captive Perenties are kept in places with winter temperatures
similar to their natural environment, so you can just dig a hole &
let the animal take care of itself, but since Canberra is much colder,
what this guy did was make a hibernation chamber with a perspex window
so he could see what the animals were doing, and with thermostats &
heaters at both ends. So he'd vary the temperature gradients & see
where the animal went, & after two winters of fiddling found the
right temperature, at which the animals wouldn't have any preference
for one end or the other of the chamber. This was basically a version
of the Test where you find the temperature that the animal is
controlling for being at by observing when efforts to control stop.

In about a year of going to herp meeetings, I haven't heard a syllable
of psych terminology out of these people, an interesting contrast to
mammal vets, who do sometimes talk about stimuli and responses.

Avery.Andrews@anu.edu.au