11.   Perhaps some earlier widespread family of insects became extinct and left its ecological niche open for the ants to move in, Grimaldi speculated.

12.   The ecological niche once filled by high-level predators is now held mainly by boats from Ballard.

13.   They display what biologists call adaptive radiation, the evolution of a founding population into an array of different species, each adapted to its own ecological niche.

14.   Things are much the same in the Hudson River Valley in New York, where hunters and the rusticating well-to-do uneasily share the same ecological niche.

15.   Though Yamaha says the new model is already back-ordered, its ancestral line has been troubled by its changing ecological niche.