Biodiversity ultimately is genetic diversity. Genetic diversity within species
is eroded before negative trends in biodiversity become evident as loss of
species or habitats. Hence, monitoring biodiversity at the genetic level may
indicate what will happen at higher levels of organisation if the trend is
allowed to continue.
There is a pervasive belief that marine ecosystems are less vulnerable to
biodiversity loss than terrestrial ones, due to marine species' high dispersal
ability and connectivity, large geographic ranges, low genetic differentiation
among populations and high genetic variation within populations. Many
studies offer compelling evidence that it is not so: loss of genetic variation
due to natural and anthropogenic factors has been detected even in marine
species with potentially high dispersal.
In this context the genetic pattern of the European barnacle Chthamalus
montagui, a species with high dispersal capability, was investigated from
three different perspectives using polymorphic microsatellite loci as
molecular markers.
The effect of structures created to protect coastal areas in the Adriatic Sea,
was investigated to test the hypothesis that artificial substrates can act as
"corridors" facilitating gene flow among previously isolated populations.
The genetic pattern of central populations was compared to that of
peripheral/marginal populations over the range of C. montagui in the UK, to
test the hypothesis that marginal and peripheral populations tend to be less
genetically variable than central ones.
For both studies results were consistent with the formulated hypotheses at
the 3 analysed loci.
Finally, a broader survey of the NE Atlantic and Mediterranean range of this
barnacle was carried out to assess spatial scales of genetic variation. A clear
differentiation between Atlantic and Mediterranean samples was detected;
however, the major source of genetic variation was within sites at a very
small spatial scale.
The information gained generates insights for marine genetic management
and conservation planning.
Date of Award | 2009 |
---|
Original language | English |
---|
Awarding Institution | |
---|
GENETIC BIODIVERSITY OF THE EUROPEAN BARNACLE CHTHAMALUS MONTAGUI
FONTANI, S. (Author). 2009
Student thesis: PhD