X-Message-Number: 26070
Date: Fri, 22 Apr 2005 17:57:37 -0700 (PDT)
From: Doug Skrecky <>
Subject: 172'nd update on fly longevity experiments

Message #26061 From: Kennita Watson <>
Subject: Re: 172'nd update on fly longevity experiments

> " If the food becomes too dry, the animals
starve. They need to watch for 'cracked' and dry food
and/or lifeless larvae. If this occurs, adding one or
two drops of water will moisten the food and should
solve the problem. On the other hand, the environment
can become too humid and the food too moist. In this
case the food will become contaminated with fungi,
which is also detrimental to the flies. Finally,
caution students not to leave the flies in direct
sunlight or other extreme environmental conditions."
   That's right, 4-24 fly food contains a mold inhibitor, but the risk of
mold appears increases dramatically if the fly food has a wet surface.
  Dehydration exerts a powerful anorectic effect even in mammals, and I
place additional plastic tape over the bottle lids to help prevent the fly
food from drying out.
  Please note that the experimental area is kept in darkness to eliminate
sunlight as a variable.

>Confusion:  I haven't seen anything online that
discusses fruit fly lifespans longer than 80 days.
Apparently it's normally about 35, and most articles
talk about lengthening it with calorie restriction,
lowered temperature, etc. to about 72.  Where does
a maximal longevity of 123 days come from, then?
The maximum longevity was derived from a simple equation which closely
mirrors the effect of temperature on Oregon-R drosophila melanogaster's
maximum longevity under good conditions. Flies can live as long as a year
under low enough temperature conditions, so temperature adjustment is very
important. Maximum longevity of 35 days has been obtained at high
temperatures. My maximum experiment control longevities have usually been
a little less than the calculated maximum longevity. Numerous
interventions can increase longevity modestly, but no breakthrough
(aside from that of temperature lowering) has been obtained yet. I'm
hoping to change this state of affairs...

Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=26070