Which pair of organisms are specifically cited as examples of "Habitat Architects" or ecosystem engineers?

Answer

Beavers and Elephants.

Beavers, who convert streams into wetlands via dams, and elephants, who manage savannas by breaking up dense vegetation, are presented as quintessential examples of ecosystem engineers that fundamentally reshape the physical environment.

Which pair of organisms are specifically cited as examples of "Habitat Architects" or ecosystem engineers?
speciesEcologyRolekeystone species