As we continued our trek among the wind-sculpted trees, the silence was broken by a demanding, guttural croak offstage to the left - evidence that a raven was in the vicinity. ...if we had walked too close to the raven's nest, we could have been pelted with rocks, since this bird is one of the few that has learned to use tools. Scientists have theorized that ravens became crafty over the centuries as they learned how to steal bits of prey caught by large predators like wolves and bears. - RB