Clouded Yellow survive UK winter

[Nigel Venters]

Hallo Morten,
I agee with you but I must have misunderstood the implications of your
first message which stated "the butterflies perform seasonal unidirectional
migrations in huge numbers!!!" Which indicates a one way trip. 
I personally think in this case, selection has enabled the butterfly to
occur in greater overall numbers by inhabiting seasonally suitable areas,
with minimum expected return to the gene pool. (Totally different from the
strategy operating in D plexippus)
regards
Nigel

Morten DD Hansen <biomddh at biology.au.dk> wrote in article
<373A75F3.2547CF65 at biology.au.dk>...
> 
> 
> Nigel Venters wrote:
> 
> > Good point except how could selection act against migration if no genes
> > from the migrants ever returned to the gene pool?
> > Nigel
> >
> 
> Indeed many migratory genes return to the gene pool. According to
Benvenuti's
> work on red admirals in Italy, there are strong migrations towards south
in the
> autumn and smaller migrations towards north in spring. Autumn migrants in
Italy
> have a fair chance of contributing to next year's generation.
> 
> kind regards
> Morten DD
> 
> --
> Morten DD Hansen, stud. scient.
> Dept. of Zoology, Institute of Bioloical Sciences
> Building 135, University of Aarhus
> Universitetsparken, DK-8000 Aarhus C
> Telephone: +45 8942 2695
> e-mail: biomddh at biology.au.dk
> 
> homepage on migrating birds and butterflies:
> http://www.biology.au.dk/~biomddh/
> 
> 
>