On Oct 17, 2006, at 2:15 AM, sukie wrote:

Lighting the night (beyond small pools of light) is quite a recent
change for humans. We forget that there are hormonal aspects of health
which darkness requirements. The latest really cool set of human
studies on the importance of darkness involved breast malignancies,
if I recall right. Yes, we diurnal being need darkness, too.

Since we've wandered into effects on people, I greatly urge everyone to
check out 
http://www.darksky.org/ . 
Especially look under "resources".

Photobiology links are here: http://www.darksky.org/links/photobio - 
a lot of stuff on the link to breast cancer, and on SAD (Seasonal
Affective Disorder). Also some on PMS and fertility. It is likely that
much of this information has some relevance to ferrets as well as to
humans.

Basically, darkness is good for you.

The only real argument for lighting is to deter crime. But there is
little evidence that security lights deter crime in a residential
neighborhood setting, where the security comes from making sure anyone
approaching the house is visible. In fact, lights sold for security
purposes are usually so bright as to cause pools of darkness, which
provide cover. Better security would be provided by dim garden lights,
which reveal without blinding.

Balanced against the dubious benefit of security lighting is the
growing evidence they do longterm medical harm. This is more and more
persuasive. Personally, I would not ever routinely provide a nightlight
to a child; it is addicting them to a source of comfort that is
ultimately bad for them. I consider it like chocolate; chocolate is a
security food for some people, but that doesn't mean I would teach my
kids to expect to have some every night before bed.

I think what bothers me the most about street lighting is the automatic
assumption that everyone wants it, and that extending street lighting
into the more rural parts of town constitutes progress. In my town,
$40,000 for high-intensity street lighting passed unremarked, while
$35,000 for badly-needed ambulance equipment caused an hour of
contentious discussion.

I think ferret owners, because our beloved ferrets are so susceptible
to the ill effects of lighting, are much more likely than most to
believe in the evidence against excessive lighting. Perhaps we can
educate the general public and change this automatic assumption that
more light is always good.

Claire

[Posted in FML 5400]