sexing caterpillars

[debruyn at ruca.ua.ac.be]

Hello,

We are analysing the influence of Cadmium pollution on the performance 
(growth, feeding efficiency, fitness, ...) of the butterfly Pararge aegeria, feeding 
on the grass Holcus lanatus. We found out that males and females give 
different results. Due to experimental conditions, it is impossible to use many 
individuals at the same time and we have to work with only few caterpillars. As 
a consequence, it is possible that due to chance, the sex ratio is strongly 
skewed in one direction, leaving too few individuals of the other sex in some 
treatments to have enough power to find significant effects.

Therefore it would be extremely helpfull if we could sex the caterpillars before 
starting the experiments. Does somebody knows whether this is possible and 
how to do it?

Thanks,

Luc De Bruyn
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University of Antwerp (RUCA)          direct phone : ++ 32 3 218.04.53
Department of Biology
Evolutionary Biology Grp              e-mail : debruyn at ruca.ua.ac.be
Groenenborgerlaan 171
B-2020 Antwerpen, Belgium             Fax: ++ 32 3 2180474
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