Zigzags of bat flight
As a child I was intrigued by all things nocturnal, bats in particular. Given the difficulty I had – as a typical diurnal child – spotting bats in daily life, much of my understanding of their habits and appearance was left to my imagination.
When I first saw the wee tree bats in Costa Rica, they were clinging to a tree alongside the Colorado River. I was amazed at their miniature size and delicate vulnerability, exposed as they were to daylight and binoculars. Several days later, while taking in the sunset near Corcovado, I happened upon a pair of bats making a circuit around and through a cabana. This seemed to be their waking ritual, as every evening I would sit in the same place to watch the sunset and they would suddenly appear at dusk, fly several rounds about the cabana, then flap away as the sky darkened.
On a separate trip later that same year, just outside Lassen Volcanic National Park, I watched the moon rise over an eastern range. Perched atop a pile of lava rocks I felt gentle, irregular whisps in the dusky air. Zigzags of bat flight flew near my head, then away, then to a rock, then back to where I sat. I watched the unpredictable circuit with delight, feeling both appreciation and apprehension (which bats are vectors for disease in humans?) to be so near these creatures. For once my tendency toward immobility served me well; I imagine bats would not approach and investigate me as carefully were I moving around.
Given my fondness for bats, I was excited when I came upon this article in the Perspectives section of the June 24, 2008 issue of PNAS today. In the piece, neuroscientists Nacham Ulanovsky and Cynthia Moss present research findings from behavioral and neurophysiological studies of bats. Their data have interesting implications for understanding “the behaving brain across species”, – Homo sapiens included – based on how bats process environmental information acquired during echolocation. I also found a review of the article on Think Gene, where a user’s comment linked to a documentary about a blind boy who uses a form of echolocation in daily life. Lacking the rich information gathered using sonar, our attempts at sound navigation may not compare to that of bats. Even so, I’m curious to see how including additional auditory information in daily life would alter my experience.