Birds: To See Them Is Not to Know Them
There is so much more to the lives of birds than we can see on the surface.
As I sit writing, watching the chickadee action at my feeder only a few yards away from my laptop, I don't just see cute, tuxedo-clad, bundles of energy. I see a social network of dominant and subordinate birds, an underworld strategy of flock switchers, and future philanderers. How can I not be awed by the world of the chickadee? Whether in your backyard or a wilderness area, knowing versus seeing birds is an entirely different experience with nature.
This can be thought of as a kind of nature literacy. If you pick up a book in a completely foreign language you may be able to enjoy the illustrations, but since you can't read the text you will get little out of the experience. By learning the natural and evolutionary history of birds, you become nature literate and can understand what you are seeing. Just as watching high-definition scenes of nature on television does not fully substitute for a window view of real nature, I would argue that viewing nature without knowing it does not fully satisfy the human need for other-than-human experiences. There is more to nature than attractive, peaceful scenery. There is a complexity and deep evolutionary history that teaches us what nature, and ourselves, are really all about.
Our ancestors had no understanding of evolution, prior to Charles Darwin's theory of natural selection, but they did have a comprehensive knowledge of the ecology of the plants and wildlife around them because it was a matter of survival. Today, many North Americans who live in suburban and urban areas are largely illiterate when it comes to nature. In Toronto, I have seen my neighbor's children scream in fear at the sight of a moth, and I know several parents who believe that the long-legged, harmless crane flies that hatch out of the lawn in late summer are in fact giant mosquitoes that must be dispatched at once with a tennis racquet or chemical attack. Yet I have met few people disinterested in learning more about the other-than-human world around them.
In the natural world, competition for sex and resources is near universal. Sex, adultery, divorce, and daily threats and acts of violence are common in the bird world of the backyard. Male birds are under pressure to impress mates, females hold out for the highest-quality males, parents must share the burden of child care, and neighbors fight over space and food. The details of how these sexual and personal conflicts are resolved are the product of a long history of natural selection that favored winners over losers, gradually changing the genetic makeup of a population one generation at a time. An evolutionary lens can be used to better appreciate the melodies of the robin, flash of red on the cardinal, and amazing journeys of our songbirds that arrive so casually in spring after traveling thousands of kilometers.
Birdsong is music to our ears, but to birds it is also a sophisticated weapon to keep competitors at bay. Songbirds often have individually distinctive songs, and gauge their aggressive response to a singer according to prior social interactions with that bird and the possible threat it poses. Not every song is created equal, and some song types are saved for the most aggressive interactions. The trill, for instance, comprises almost identical notes repeated in a fast succession that requires a precise coordination of vocal muscles and airflow. The sound produced is a trade-off between how quickly a bird can repeat the individual units versus the frequency range that each unit spans, such that rapid broadband trills indicate high male quality and signal that the singer should be treated as a serious challenge. Females also listen to songs, and prefer males with more complex songs or a bigger repertoire. My research on hooded warblers has shown that males with a weak song performance have mates who sneak off territory to obtain extra-pair copulations from neighboring males that sing at a higher rate. Most songbird neighborhoods are social networks where individual qualities are broadcast through song. A male territory owner recognizes his rivals individually, and continually updates his assessment of each rival's immediate and future threat, and meanwhile females are eavesdropping on male performances.