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Psyche 
[Vol. 94 
In many ways, female polyandry in lacewings is much like that in 
Drosophila, particularly D. melanogaster. These females re-mate a 
few times during their lifetimes, but often fertilize most of their eggs 
with the sperm of one male (Pyle and Gromko, 1978). In D. mela- 
nogaster, about 78% of the sperm must be depleted before the female 
will re-mate (Ibid.). And although a female’s total complement of 
eggs can in theory be fertilized from one copulation, multiple mat- 
ings nonetheless increase lifetime egg productivity by a small but 
significant amount (Gromko et al. 1984). These flies, like lacewings, 
achieve such fecundity patterns by a similar mechanism: females 
totally lose sexual receptivity after copulating, and regain it only 
when stored sperm has been nearly depleted. 
Male Polygyny. 
The results of the male multiple-mating experiments are the most 
difficult to interpret (Table 6, Fig. 4). For the most part, individual 
males of C. plorabunda and C. downesi showed a rather steep 
decline in their ability to inseminate females with successive mat- 
ings. Both tested males of C. downesi conform to this pattern, so 
that after two or three matings, they were unable to father more 
than a few progeny, even though each mated 10 times. Similarly, 
most of the 8 C. plorabunda males appeared to run low on sperm 
after a series of consecutive matings; for these and the C. downesi 
“normal” males, reproductive potential was only slightly greater 
than that of females, averaging between 1000 and 2000 progeny over 
a lifetime (Table 6). However, one male of C. plorabunda sired over 
9600 offspring during his 3.5 month reproductive life, mating 30 
times. What appears to be a decline in his fertility at the time of his 
17th and 18th matings actually reflects the old age of the females 
used as his mates; once younger partners were recruited, post- 
copulation fecundity increased to levels nearly as high as those 
recorded early in the male’s life (Fig. 4). Of course, it can be argued 
that data based on so few males are of little use. However, we were 
not so much concerned with average male mating performance and 
fertility as we were with maximal values, to determine whether indi- 
vidual males could inseminate many females and sire several thou- 
sands of offspring. Consequently, the results here can only 
underestimate the real reproductive potential of males of these spe- 
cies; a single vigorous, prolific individual is sufficient to highlight 
the differences between males and females. 
