Andy Reynolds in AmNat this month: Beating the Odds in the Aerial Lottery: Passive Dispersers Select Conditions at Takeoff That Maximize Their Expected Fitness on Landing
[C]ertain genotypes are evolutionarily inaccessible under rapid environmental change. Rapidly deteriorating environments not only limit mutational opportunities by lowering population size, but they can also eliminate sets of mutations as evolutionary options.
From Lindsay et al. 2013