THE NATURALIST’S NOTEBOOK: Little Brown Birds
Thoughts on thrushes, faces, and friends
CORRECTION TO THIS ARTICLE: Due to an editing error, a previous version of this column neglected to specify the following in a quote: "...Fiat Spider 850; you don't often see those around anymore."
Apparently, it’s now November, since it is already dark when I get out of class. In the birdwatcher’s calendar, this cold, wet season is the time to go out and search for a dozen species of sparrows and thrushes. These birds are all small and brown and go by the informal name of Little Brown Bird (LBB for short). A typical sighting goes like this: “Look, something moved in the grass! Oops, I scared it, it’s flying away.” “It’s gone. What was it?” “Oh, an LBB.”
To most non-birders, all LBBs look pretty much the same. I was recently walking along Memorial Dr. with a friend when a ball of nondescript feathers flew past into a bush and stood skulking in the shadows, bobbing its tail up and down. I remarked that it was a hermit thrush. She was confused. “But how can you tell?” (And why do you care?)
“Well,” I said, “the bird had a reddish tail, black spots on the breast feathers, and the bill was very thin.” Actually, though, I wasn’t thinking about spots. Most people read their native language by recognizing whole words, instead of spelling everything letter by letter. In much the same way, this bird just looked like a hermit thrush.
What is it that drives birdwatchers to seek out a thrush, when they can surround themselves with similar-looking house sparrows for the price of a few breadcrumbs? To me, much of the appeal lies in personal associations: the sight of a hermit thrush brings forth a flock of thrushes in my memory. I imagine a haunting cascade of melody heard in the woods just before dusk — a song that the house sparrow cannot hope to rival. I see a nest of tiny blue eggs hidden in a bush. And I think of my home in Vermont, where this species is the official state bird.
My dad has a similar passion for cars, which baffles me just like the thrush baffled my friend. Walking along the street, he remarks, “That’s a Fiat Spider 850; you don’t often see those around anymore.” “And it’s blue,” I add helpfully. I grew up with birds, but he grew up with cars. Indeed, many kids develop a passion for birds, or cars, or dinosaurs, or another kind of LBB. What drives them, while so young, to identify and classify things, and how are they able to pick out small details, seemingly instinctively?
Perhaps the answer lies in human facial recognition. It’s vital to our survival that we are able to distinguish between different people in some way. From a very young age, most babies learn to make eye contact and treat a human face as a fundamentally special thing. A recent study (Pascalis et al. 2005) showed that six-month-olds can also recognize individual macaques (a kind of monkey) by their faces, but that this ability is lost by the age of nine months, since presumably, most infants are not raised by macaques. Thus, it seems like we are hard-wired to find faces to recognize, but that the exact character of those faces is malleable. It thus makes sense that the neurological mechanism for facial recognition can be co-opted to many different situations, enabling us, especially while young, to pick up details rapidly and organize a collection of similar images into a coherent classification: a phylogeny of birds, or an auto registry.
Recognition is hard. Humans still beat computers hands down, as anyone who has tried Facebook’s facial recognition tool can testify. Biologists are working on automated software for identifying birds, but the technology still has a long way to go.
Given the magnitude of the task, it’s hardly surprising that many of us have trouble distinguishing between members of our own species. Studies have shown that women are better at it than men. People with some kinds of autism may be worse at holistic recognition, relying instead on specific traits like eye color and hairstyle, the human equivalent of spotted feathers. There is also the cross-race effect, e.g. “all Asians look the same to me.” Among people who grew up without exposure to other races, such recognition gaps are, perhaps, hardly more surprising than the inability to distinguish a thrush from a sparrow. While it is folly to assume that unfamiliar people or birds look exactly the same, correct identification certainly requires practice and motivation.
If birdwatchers are channeling facial recognition skills, surely that also helps explains some of the appeal of birding. A face that we know brings to mind not just a name but also a host of memories and emotions. It may seem that the knowledgeable naturalist is merely a textbook that notes field marks and lists species, but the truth is deeper: birds really can be feathered friends, with some of the visceral appeal of human friends. The automotive enthusiast does not simply like cars because they are diverse or have complex mechanisms that are interesting to understand. Observation is not always a passive enterprise, but can feel akin to an interpersonal bond.
When someone asks me why I care about that nondescript bird in the bushes, I wonder if they’ve stopped to think about how much they’re observing, and what they have a relationship with — starting with the LBB they’re talking to.