260
M.L. Cancela et al.
to estimate the total number of minke whales entering the trade. Using a capturerecapture model they estimated that the most likely number was approximately
double of the officially reported number.
These examples are representative of the potential of genetic methods for
fisheries enforcement and traceability. However, the genetic analyses are often
hampered by the low levels of genetic differentiation commonly found among populations of marine fish. Accordingly, the statistical power for determination of the
origin of individual or samples of fish rarely suffices for forensic purposes. Since
the power for GSI is ultimately linked to the number of loci applied and the levels
of genetic differentiation at marker loci (e.g. Koljonen et al. 2005 and references
therein) there are large perspectives for future application of genomic methods.
7.7.2.4 Integrating Evolutionary and Ecological Functional Genomics
with the Environment
Divergent selection should act to reduce gene flow and hence contribute to speciation (Coyne and Orr 2004). However, how adaptations identified at the genomic
levels relate to the external phenotype in terms of life-history, behavioural and physiological traits, and likewise to the genetic architecture of adaptive trait variation
remains largely unknown. Most arguments have been theoretical with surprisingly
little empirical knowledge about the genetic basis of adaptation and the role of
selection (Orr 2005). Evolutionary and Ecological Functional Genomics (EEFG)
explores the evolutionary mechanisms that underlie ecological traits and how these
traits affect evolutionary fitness (Feder and Mitchell-Olds 2003). It requires a rather
challenging simultaneous use of molecular, cellular, organismal, population and
ecological approaches. Initially integrated studies were limited to a few classical model species (e.g. the plant Arabidopsis thaliana). The biology of these taxa
was sufficiently well known at the various organizational levels to allow an EEFG
approach. Understandably, the study of evolution in a natural setting requires more
and different types of “model” organisms. Fortunately, the number of taxa with
a dense genomic background has increased. Following the ecological models of
three-spined stickleback (Kingsley et al. 2004) and mummichog Fundulus heteroclitus (Oleksiak et al. 2002), a growing number of fishes relevant to fisheries (and
aquaculture) complement the list: the salmonids rainbow trout Oncorhynchus mykiss
(Rexroad et al. 2005), Atlantic salmon (Moen et al. 2008a), brown trout Salmo trutta
(Gharbi et al. 2006) and whitefish Coregonus clupeaformis (St-Cyr et al. 2008), the
perciforms European sea bass (Volckaert et al. 2008), gilthead seabream Sparus
aurata (Sarropoulou et al. 2005b) and Nile tilapia Oreochromis niloticus (Cnaani
and Hulata 2008), the gadid cod Gadus morhua (Symonds and Bowman 2007), the
flatfishes European flounder Platichthys flesus (Williams et al. 2003), olive flounder
Paralichthys olivaceus (Kang et al. 2008) and turbot Scophthalmus maximus (Bouza
et al. 2007), and the channel catfish Ictalurus punctatus (Liu et al. 2008).
Adaptive radiation is most classically studied on external phenotypes and lifehistory traits, often a single trait at a time. A prime example among fishes where an
impressive body of knowledge of fast evolution has accumulated is the three-spined
M.L. Cancela et al.
to estimate the total number of minke whales entering the trade. Using a capturerecapture model they estimated that the most likely number was approximately
double of the officially reported number.
These examples are representative of the potential of genetic methods for
fisheries enforcement and traceability. However, the genetic analyses are often
hampered by the low levels of genetic differentiation commonly found among populations of marine fish. Accordingly, the statistical power for determination of the
origin of individual or samples of fish rarely suffices for forensic purposes. Since
the power for GSI is ultimately linked to the number of loci applied and the levels
of genetic differentiation at marker loci (e.g. Koljonen et al. 2005 and references
therein) there are large perspectives for future application of genomic methods.
7.7.2.4 Integrating Evolutionary and Ecological Functional Genomics
with the Environment
Divergent selection should act to reduce gene flow and hence contribute to speciation (Coyne and Orr 2004). However, how adaptations identified at the genomic
levels relate to the external phenotype in terms of life-history, behavioural and physiological traits, and likewise to the genetic architecture of adaptive trait variation
remains largely unknown. Most arguments have been theoretical with surprisingly
little empirical knowledge about the genetic basis of adaptation and the role of
selection (Orr 2005). Evolutionary and Ecological Functional Genomics (EEFG)
explores the evolutionary mechanisms that underlie ecological traits and how these
traits affect evolutionary fitness (Feder and Mitchell-Olds 2003). It requires a rather
challenging simultaneous use of molecular, cellular, organismal, population and
ecological approaches. Initially integrated studies were limited to a few classical model species (e.g. the plant Arabidopsis thaliana). The biology of these taxa
was sufficiently well known at the various organizational levels to allow an EEFG
approach. Understandably, the study of evolution in a natural setting requires more
and different types of “model” organisms. Fortunately, the number of taxa with
a dense genomic background has increased. Following the ecological models of
three-spined stickleback (Kingsley et al. 2004) and mummichog Fundulus heteroclitus (Oleksiak et al. 2002), a growing number of fishes relevant to fisheries (and
aquaculture) complement the list: the salmonids rainbow trout Oncorhynchus mykiss
(Rexroad et al. 2005), Atlantic salmon (Moen et al. 2008a), brown trout Salmo trutta
(Gharbi et al. 2006) and whitefish Coregonus clupeaformis (St-Cyr et al. 2008), the
perciforms European sea bass (Volckaert et al. 2008), gilthead seabream Sparus
aurata (Sarropoulou et al. 2005b) and Nile tilapia Oreochromis niloticus (Cnaani
and Hulata 2008), the gadid cod Gadus morhua (Symonds and Bowman 2007), the
flatfishes European flounder Platichthys flesus (Williams et al. 2003), olive flounder
Paralichthys olivaceus (Kang et al. 2008) and turbot Scophthalmus maximus (Bouza
et al. 2007), and the channel catfish Ictalurus punctatus (Liu et al. 2008).
Adaptive radiation is most classically studied on external phenotypes and lifehistory traits, often a single trait at a time. A prime example among fishes where an
impressive body of knowledge of fast evolution has accumulated is the three-spined