Article,
Dissecting differentiation landscapes: a linked selection's perspective
Journal of Evolutionary Biology, 30 (8): 1501-1505 (2017)
DOI: 10.1111/jeb.13108
Abstract
Eased on the assumption that locally accentuated dif-
ferentiation within genomes represents a footprint of
positive selection or barriers to gene flow, the last dec-
ade’s quest for genomic regions involved in adaptation
and speciation has led to the description of differentia-
tion landscapes in numerous taxa (e.g. Ellegren et al.,
2012; Jones et al., 2012; Renaut et al., 2013; Soria-Car-
rasco et al., 2014). A major common pattern emerging
from this research is a usually striking heterogeneity of
differentiation along the genome, with regions of
accentuated differentiation widespread across otherwise
less differentiated genomes – as widespread and in sev-
eral cases so markedly codistributed with genomic fea-
tures (e.g. White et al., 2010; Burri et al., 2015), as to
question these regions’ role in speciation (Noor & Ben-
nett, 2009; Nachman & Payseur, 2012; Cruickshank &
Hahn, 2014).
In their review, Ravinet et al. (2017) discuss the com-
plex evolution of differentiation landscapes, involving
multiway interactions of diverse processes, and propose
a road map through the challenge of disentangling the
footprints of speciation from those of confounding pro-
cesses. Here, I outline a few complementary angles
from a linked selection’s perspective. (i) I revisit the
effects of linked selection, suggesting that they may
depend on the dynamics of recombination rate evolu-
tion. (ii) I then emphasize the need for analyses to tar-
get the most likely footprints of speciation given a
system’s evolutionary history and its history of linked
selection. (iii) Finally, I highlight how long-range
sequencing will empower the characterization of geno-
mic landscapes beyond differentiation.
