Lessons in Birdsong

Despite the chattering that marks this and every political season, it turns out that learned vocalization is pretty rare in nature.

Aside from humans, only whales, dolphins, bats and several species of songbirds (and perhaps elephants and sea lions) exhibit learned vocalization, which basically means the inborn ability to hear, imitate and repeat sounds. This ability differs from, say, a dog’s bark, which may communicate to its owner that it’s chow time, but the actual sound is an inborn and not a learned vocal trait.

For the past decade, neurobiologist Erich Jarvis (photo) of Duke Medical Center has used songbirds as models to probe the genetics and molecular biology of vocal communication. In a recent lecture in the Genomes@4 series sponsored by the Duke Institute for Genome Sciences & Policy, Jarvis recounted -- complete with whistling and other sound effects -- some highlights of his laboratory’s research. The findings have gained widespread scientific and popular attention, as reported here, here and in a video here.

Among recent efforts, Jarvis and his colleagues have found that the more birds sing, the more genes become active, with increased numbers of genes in their brain cells exhibiting heightened activity. Another case of use it or lose it -- or never get it.

And not to give away secrets, his group has just made some intriguing observations by analyzing birds as they hop and sing at the same time -- that is, while several types of brain and neuromuscular activities are under way. As the group will report in an upcoming issue of the online, open-access journal PLoS, these observations suggest that production of learned vocalizations ignites a number of specific genes that have been carried over from an ancient regulatory system.

Fat Habits

In the midst of fat season -- the time of longer nights that provide more time for munching -- some recent advice about eating is welcome. And a bit comforting.

Several studies suggest that eating is often an automatic behavior triggered by environmental cues that people don’t recognize or can’t ignore. In other words, it’s not all my fault.

As might be expected, the media have jumped on this notion.

One summary in the Los Angeles Times, which has been picked up in scads of other publications, cites psychologist Wendy Wood (photo) of Duke’s Social Science Research Institute, who studies how habits influence everyday behaviors, including food choices. Some of her work is reported here and here, and another interesting study by Rand Corp. scientists is reported here.

It turns out that perhaps 45 percent of human behavior is repetitious and unthinking. And Woods and others have found that people fall back on their habits, such as buying fast food or scarfing up doughnuts in the conference room, even when they intend to do otherwise.

A possible silver lining is that by changing their “food environment,” people can reduce their chances of acting on autopilot habits. For example, if you regularly stop for an extracreamy latte and pastry on the way to work, change your commuting route. If you tend to raid the refrigerator, put more healthful foods on the handiest shelf.

Many observers also suggest that government has a role to play in creating “safer” food environments by, for example, curbing food advertising and limiting access to ready-to-eat foods. Good luck with that -- expect lots of cries of Big Brother -- but it certainly is food for thought.