What metaphors are used in Crossing Open Ground by Barry Lopez?

In the final section of the essay titled, The Passing Wisdom of Birds, Lopez returns to the image of Cortes burning the bird sanctuaries, arguing that the same kind of greed and desire for power that motivated that action motivates similar actions today. He develops this argument further by saying that observation and contemplation of wild animals and how their actions provide "the central metaphors by which we have taken satisfaction in our ways and explained ourselves to strangers", can lead us in the necessary directions. He provides an example of such a metaphor by returning once again to the image of Cortes burning the birds, commenting that in a moment of contemplating a flock of birds in flight, it becomes "possible to move beyond a moment in the Valley of Mexico when we behaved as though we were insane."