X-Message-Number: 22367
Date: Sat, 16 Aug 2003 11:58:27 -0700 (PDT)
From: Doug Skrecky <>
Subject: 100'th update on fly longevity experiments
This is the 100'th update of my fly longevity experiments. Average
temperature was 23.1 C during this run. Estimated maximal longevity using
the formula (363 - T*11.2) is 104 days.
In celebration of my 100'th fly experiment, I've decided to retest all
the supplements in duplicate, that produced at least one fly that reached
over 105 days of age in the first 99 experiments. These are always from
experiments conducted during the winter, when indoor temperatures are
lower. The supplements are as follows:
Kambiz pomegranate paste (124 days - run# 87),
Knudsen elderberry nectar [freeze concentrated] (118 days - run# 36)
Sun-Rype apple juice + vit C (107 days -run#36)
Huaqi hawthorn juice (106 days - run# 84)
Taisun Enterprises starfruit juice (106 days - run# 83)
Nu'O'C Bi Dao white gourd juice (106 days - run# 83)
For this experiment a few substitutions had to be made, as neither
fresh pomegranate paste, nor the starfruit juice were currently available.
A very old and somewhat smelly bottle of pomegranate paste was still in my
fridge, so I used that. I also bought some fresh raw starfruit and blended
it into a homemade juice.
As an added wrinkle I had noticed some survival benefit early in run
#99 to some bottles kept in darkness. I decided to place every second
bottle in the dark at day 11 of this experiment, to further test the
effect of light deprivation. A number of published experiments have found
a modest survival advantage to flies stored in the dark.
Darkness had parodoxical effects on the control bottles this time. The
dark control had slightly increased maximum longevity, but at the same
time decreased average longevity. This parodox might be due to my using a
smaller pint size milk bottle, instead of the standard quart size for the
dark control. When I had started this experiment, I had intended to test
only the effect of bottle size on the controls. A smaller bottle, means
flies will come in physical contact more often, and possibly exchange
viral infections more quickly.
Storage in the dark increased maximum survival in the control, apple,
elderberry, hawthorn, and pomegranate bottles, but reduced it in the
Starfruit, and white gourd ones. Is all this due to chance? (I further
test dark storage in run #101.)
All supplements increased maximum survival. White gourd juice garnered
the maximum survival sweepstake, with a winning score of 88 days. However
hawthorn juice provided more consistent results, and gained the runner-up
position at 82 days. These are just 24%, and 15% above the control maximum
longevity of 71 days.
Run #100 Percent Survival on Day
supplement 27 32 37 43 48 53 60 66 71 76 82 88 93
__________________________________________________________________
control 86 86 86 67 62 52 24 5 0 - - - -
+(dark after day 11) [SB] 65 70 50 25 25 10 10 5 5 0 - - -
apple juice 70 70 61 39 39 30 13 9 0 - - - -
+(dark) 79 79 74 63 53 37 32 11 5 5 0 - -
elderberry nectar FC 81 81 81 63 63 63 38 13 6 6 0 - -
+(dark) 94 94 83 72 61 61 50 39 28 11 0 - -
hawthorn juice 88 88 79 75 71 67 42 25 13 13 0 - -
+(dark) 100 100 83 78 78 57 48 48 26 22 4 0 -
pomegranate paste 1/2 tsp 85 80 80 70 60 50 35 15 0 - - - -
+(dark) [old paste] 85 85 85 75 55 55 25 15 10 5 0 - -
starfruit juice,raw 95 79 79 68 58 58 37 21 11 5 0 - -
+(dark) 83 83 67 50 33 25 8 0 - - - - -
white gourd juice 81 81 76 67 48 48 38 24 19 10 10 5 0
+(dark) 88 88 81 31 25 13 0 - - - - - -
Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=22367