Hello, I would like to repost the following article:

>>> Posting number 21211, dated 20 Feb 1998 15:35:15

Quotation:

Survivorship of foraging honey bees
P.K. Visscher and R. Dukas
Insectes Sociaux 44: 1-5, 1997

Summary
We recorded lifetime foraging activity and survivorship of individual
honey bees foraging under natural settings. Bees experienced a
constant probability of death per unit time away from the colony.
This leads to a log-linear survivorship curve of type II. Most bees
died before reaching senescence. The patterns of survivorship are
likely to influence the evolution of foraging behavior, and this
results suggest that age-independent factors such as predation could
play a strong role in selection of foraging range and other
parameters. Our result is contrary to the pattern expected if
survivorship of individual honey bee foragers is determined
largely by a limited lifetime budget of energy expenditure,
which would imply a low probability of mortality early in
a bee's foraging life, followed by a sharp increase in mortality late
in life, when either physiological or mechanical wear cause death.

End of quotation

Part of one of their figures:

The observed distribution of total lifetime foraging duration for 33
bees

          _________
       7 |    |    |
         |    |    |_________
Bees   6 |    |    |    |    |
         |    |    |    |    |
dying  5 |    |    |    |    |
         |    |    |    |    |
 per   4 |    |    |    |    |
         |    |    |    |    |
10 hr  3 |    |    |    |    |
         |    |    |    |    |_________
inter- 2 |    |    |    |    |    |    |
         |    |    |    |    |    |    |______________
val    1 |    |    |    |    |    |    |    |    |    |
         |    |    |    |    |    |    |    |    |    |
         0   10   20   30   40   50   60   70   80   90   100

                      Hours of foraging


--
Michael Haberl
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http://staff-www.uni-marburg.de/~haberl/
http://staff-www.uni-marburg.de/~ag-biene/