CONCLUSIONS
As global climate change becomes an increasing threat to biodiversity,
our understanding of the adaptive potential of species and the
integration of this information into management strategies will be
critical in preventing species loss. Thus, determining the rates and
mechanisms of species responding to environmental change is an important
goal for the conservation of species at risk. Our use of a candidate
gene approach allowed for the a priori selection of a gene
with characterized functions, which we hypothesized to be under
selection in our species of interest, Canada lynx. We detected multiple
signatures of selection in both an intra-specific comparison of
closely-related species (Canada lynx and bobcat), and inter-specifically
in Canada lynx at the NR1D1 clock gene cTNR. The possibility for
hybrid-mediated gene flow via introgression between lynx and bobcats can
erode the pure genomes of the parental species, and can carry positive
and/ or negative consequences by, for example, facilitating the
northward range expansion of bobcats. The small yet significant
influence of both environment and space on this clock gene locus within
the eastern distribution of lynx suggests that environmental factors are
influencing the distribution of genetic variation at this locus, some of
which may be tightly correlated with space (i.e., latitude). More
broadly, signatures of selection on the NR1D1 locus within lynx
suggests that cTNR loci may play a role in generating functional
diversity within mammals that can be influenced by selection.
Ultimately, the high mutation rates of cTNR loci may allow for
contemporary rates of evolution in wild populations. While selection on
cTNR loci has already been suggested in wild populations of birds
(Johnsen et al., 2007; Liedvogel et al., 2009) and fish (e.g., O’Malley
et al., 2010), to our knowledge this is the first report that provides
evidence for selection on a cTNR locus in a highly vagile wild mammal.
Although cTNRs are largely under-represented in the wildlife literature,
they may be important targets of study for those aiming to understand
the rapid adaptive potential of species under environmental change.