The problem is that most quick adaptation is through the selection of an existing allele(s). If the species has no allele that confers necessary adaptations it is less likely to survive. The survivability of a species is heavily dependent on the speed of the environmental changes; the changes we see occurring in present ecosystems are too fast and furious for many species to survive.
Diversity will drop dramatically before vacant niches encourage a rebound diversity increase. What will that cost us? - How will that affect our survivability. - What are the ethical costs?
Interesting....on all counts. Especially in terms of costs. Since we cannot, to any significant degree, control global warming or cooling, can we adapt quickly enough to survive over other species who have already physically adapted?