| | |
Summary: What led to the pervasiveness of hybrids
between Cx. pipiens and Cx. molestus in
North America, but not in Europe and Af-
rica, still remains to be determined. In
southernmost Europe, we identified two
populations with a few hybrid individuals,
as well as populations with pure Cx. pipiens
signatures and populations with a mix of
pure Cx. pipiens and pure Cx. molestus
signatures (Fig. 2). Indeed, previous
allozyme- based studies indicated the exis-
tence of populations in Italy with a mix of
the two forms (26) but a very low rate of
hybridization (1%), probably because of
their different mating behaviors (26). The
rarity of southern European hybrids and our
failure to find hybrids in northern Europe
may be due to their low fitness and inability
to diapause. Importantly, the introduction to the
United States of separate populations of Cx. pipi-
|
