Huge numbers of Rufous Hummingbirds cruise into southeastern Arizona during their fall migration, arriving after the summer monsoons have inspired a fall bloom, lush in good years. As the hummers arrive, the agaves which pepper the mountain slopes come into flower, providing nectar and pollen for hummingbirds, orioles and nectar bats.
Flame in the Canyon: Rufous Hummingbird
(Watercolor by Narca)
It's possible to sit at the southern terminus of a small mountain range (as I have done at San Luis Pass in the Animas Mountains), and watch a stream of hummingbirds reach the end of the agaves, then launch themselves over the intervening grasslands, heading south for the winter.
Watching the hummingbirds flow south, watching the Vs of geese overhead, seeing the pulse of salmon returning up their natal streams to breed, we are immersed in the great cycles of planetary life.