1 Each animal has its ecological niche.
2 Various ecological issues have come to the fore since the discovery of the hole in the Earth's ozone layer.
3 The Black Sea is facing ecological catastrophe as a result of pollution.
4 The Global Communications Group links ecological and other political activists via the Net.
5 The ecological disaster is partly a product of letting everything rip in order to increase production.
6 Spanish authorities have prevented a major ecological disaster by diverting a flow of toxic spill away from one of Europe's leading national parks.
7 He has actual professional qualifications in ecology and conservation.
8 Fossils preserved in sedimentary rocks will display that era's primary forms, reflective of that era's ecology and life's adaptations to best exploit it.
9 Social systems evolve in close relation to ecology.