Dm. Fonseca et al., Bottlenecks and multiple introductions: population genetics of the vector of avian malaria in Hawaii, MOL ECOL, 9(11), 2000, pp. 1803-1814
Avian malaria has had a profound impact on the demographics and behaviour o
f Hawaiian forest birds since its vector, Culex quinquefasciatus the southe
rn house mosquito, was first introduced to Hawaii around 1830. In order to
understand the dynamics of the disease in Hawaii and gain insights into the
evolution of vector-mediated parasite-host interactions in general we stud
ied the population genetics of Cx. Quinquefasciatus in the Hawaiian Islands
. We used both microsatellite and mitochondrial loci. Not surprisingly we f
ound that mosquitoes in Midway, a small island in the Western group, are qu
ite distinct from the populations in the main Hawaiian Islands. However, we
also found that in general mosquito populations are relatively isolated ev
en among the main islands, in particular between Hawaii (the Big Island) an
d the remaining Hawaiian Islands. We found evidence of bottlenecks among po
pulations within the Big Island and an excess of alleles in Maul, the site
of the original introduction. The mitochondrial diversity was typically low
but higher than expected. The current distribution of mitochondrial haplot
ypes combined with the microsatellite information lead us to conclude that
there have been several introductions and to speculate on some processes th
at may be responsible for the current population genetics of vectors of avi
an malaria in Hawaii.