More and more people are familiar with shifting baselines syndrome, or the idea that each generation tends to measure change in terms of its own times, and thereby fails to recognize the gradual accumulation of change over generations.The effect has been recognized since at least the 19th century, but the viral term “shifting baselines” was coined in 1995 by fisheries scientist Daniel Pauly, who noted that fisheries managers often recognize the decline of fish stocks over their own careers without considering that similar declines may have been going on for decades or even centuries–a “gradual accommodation,” Pauly said, of “creeping disappearance.” As it turns out, though, we can do our forgetting much more quickly than that. Before reading any further, please watch this brief video of a magic trick. This is just one example of the phenomenon of change blindness, in which we fail to notice the obvious. Change blindness is hot material in Psych 101 courses, but is only now being applied to the ways we see the natural world.
The key finding is that it doesn’t necessarily take generations of time to miss accumulating changes; in the video, it takes about one minute. In a study published last year in Conservation Letters, for example, about a third of people in a Yorkshire, UK, village reported that the three most common birds in the area are the same today as they were 20 years ago. In fact, they are entirely different. The failure to notice changes (change blindness) has resulted in people reporting current conditions as the same as past ones (personal amnesia) with the result that natural conditions have altered unnoticed (shifting baselines). I asked University of British Columbia psychologist Ron Rensink, whose change blindness research is cited in the Conservation Letters paper, whether he thought the application to our perception of nature was legitimate. “Essentially, the work on change blindness supports the idea that we construct a relatively sparse memory in our minds, with the world itself acting as its own detailed memory,” he says. “This is fine as long as the world doesn’t change too much. But if it does, relatively large changes could go unnoticed.” I like that idea: the world around us as a kind of living remembrance—yet another way to see natural systems as extensions of ourselves. Unfortunately, Rensink adds, we are especially bad at recognizing gradual changes to that landscape of memory. How dramatic can the effect be? Rensink points to research in which people were shown a restaurant scene that slowly—one object at a time—changes into an outdoor scene. “People eventually notice that they’re not in a restaurant any more, but it does take a while.”
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And now, a nibble of natural-history popcorn: Turkeys can swim. I read this in a book published in 1860, and probably much like you, I doubted it. With the powers of field naturalism through YouTube, however, I found proof. Damn thing swims like a duck. Common knowledge in the 19th century, apparently, and completely forgotten today. Oh the loss, the terrible loss…
Cited in this post: S.K. Papworth, J. Rist, L. Coad, and E.J. Milner-Gulland, “Evidence for shifting baseline syndrome in conservation,”Conservation Letters 2 (2009) 93-100.
