At a number of sites (e.g., Zuytdorp and Nanga Station), unprecedented levels of sympatry or parapatry
were documented (as 'Eucyrtops'; Main et al.
How speciation can proceed in the face of gene flow between potentially interbreeding populations, including among parents and newly formed hybrid species (Andrew et al., 2012; Renaut et al., 2013), is especially revealing of the challenges associated with habitat specialization under parapatry
. Gene flow can dilute the adaptive differences that selection generates between divergent populations; this may be especially problematic when one population is significantly larger than the other, as in the case of a newly divergent population found adjacent to an ancestral population, or in the presence of asymmetric gene flow (Ellstrand, 2014).
and niche complementarity of Peruvian desert geckos (Phyllodactylus): the ambiguous role of competition.
This distributional pattern is commonly referred to as parapatry
(Key, 1982; Bull, 1991).
Variable progress toward ecological speciation in parapatry
: stickle-back across eight lake-stream transitions.
Phylogeographic analyses of the 30[degrees]S south-east Pacific biogeographic transition zone establish the occurrence of a sharp genetic discontinuity in the kelp Lessonia nigrescens: Vicariance or parapatry
for the fish congeners Lythrurus snelsoni and L.
Accumulating post-zygotic isolation gene in parapatry
: a new twist on chromosomal speciation.
Chromosomal polymorphism, racial parapatry
Recently, Turner and Mallet (1996) suggested that mimicry rings in Heliconius did not originate via "biotic drift" in allopatry and in conjunction with Pleistocene climatic-vegetational fluctuations (as proposed by Brown et al., 1974), but rather by mutation and random drift in parapatry
. Novel color patterns then spread to become predominant in local areas and later over wide areas by the migration of clines.
and encounter competition between chipmunk (Tamias) species and the hypothesized role of parasitism.
Miller (1964: 256) believed that "Two species may exist in close proximity and their ranges may even interdigitate, but they maintain a relationship of contiguous allopatry and do not form mixed-species populations." Today, "contiguous allopatry," in which otherwise sympatric species are separated ecologically, is known as parapatry