Additional information on isolation and apparent adaptation:

> In this paper, I have described a view of ecology and speciation that is very different from those discussed in the recent literature. I have outlined how phylogenetic niche conservatism, rather than ecological divergence, contributes to the formation of geographically isolated lineages, the necessary first stage of the most common (allopatric) mode of speciation. 

> Evolutionary biologists have often suggested that ecology is important in speciation, in that natural selection may drive adaptive divergence between lineages that inhabit different environments. I suggest that it is the tendency of lineages to maintain their ancestral ecological niche (phylogenetic niche conservatism) and their failure to adapt to new environments which frequently isolates incipient species and begins the process of speciation. 

> Recent empirical and theoretical work on the evolution of geographic ranges and ecological niches suggests that four factors should maintain the ancestral niche and limit local adaptation during vicariance: lack of variability, natural selection, pleiotropy, and gene flow. The most obvious factor is a lack of variability in the traits that would allow dispersal across the barrier (e.g., Bradshaw 1991; Case and Taper 2000). This lack of variability may itself be the result of natural selection, weeding out variation in traits that would promote or allow dispersal out of the niche.

Wiens, J. J. (2004). Speciation and ecology revisited: phylogenetic niche conservatism and the origin of species. Evolution, 58(1), 193-197.

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