While on vacation with non-scientist friends in Mexico, Diana Tomchick, a biochemist at the University of Texas, Southwestern, found that an episode of Kirsten Sanford's "This Week in Science" podcast with a heated debate on global warming sparked one of their own.
Leach and Tomchick aren't the only scientists listening to science podcasts - a manifestation of the growing trend of distributing free, radio-style programs online as downloadable mp3 files. "I love podcasts," says Jane Cox, a neurobiologist at St. Louis University. "They keep me up to date when I don't have the time to read journals or newspapers."
With the help of iPods and other mp3 players, podcasting "allows [subscribers] to listen where and when they want, 24/7," says David Lemberg, a science media consultant. Andrew Leyden, president of PodcastDirectory.com, estimates that "eighteen months ago, there were only 50 podcasts," while there are "easily 20,000 if not double that now." He says about three percent of the nearly 10,000 podcasts he lists on his site are science-oriented.
The ratio of podcasts to podcast listeners, however, remains higher than for traditional media: According to an April study by Forrester Research, only one percent of online households in North America regularly download and listen to podcasts, another two percent do so occasionally, and 17% are interested in starting. Out of nearly 700 readers surveyed by The Scientist, half say they've never listened to a podcast.
The form is "still very young," says Charlene Li, an analyst at Forrester, and many potential listeners still don't know how to find or download them. That was also a concern for many of those we surveyed, as was the preference for reading over listening when it comes to science. But there's no denying the medium's growth: 85% of those surveyed who listen to podcasts started in the past year, and 49% started in the past five months alone.
A MEDIUM IS BORN
One of the very first science podcasts-"Science @ NASA"-was developed late in the summer of 2004 to distribute news and features about the space program, says Leyden. Since then, newspapers such as The New York Times and The Guardian have repackaged their science coverage into podcasts, while National Public Radio (NPR) affiliates have made their science programs available on the web.
In the beginning, there was a large presence of homegrown science podcasts, made by students and people who were just interested in science, says Scientific American editor in chief John Rennie. After all, making a podcast is quite simple (see How to make your own). "What you're seeing [now] is a major commercialization of it, that major media outlets want their names on the shelf," says Scientific American "Science Talk" podcast host Steve Mirsky. There's Nature with "Nature podcast," Seed, with "New and Notable," and The Scientist, with "The Week."
Lack of name recognition has "tended to push... some of those smaller independent podcasts lower down in the ranks of popularity, simply because things like NPR or The New York Times or Scientific American already have existing platforms of visibility," Rennie says. And while these provide more consistent production quality and more reliable information for an intrinsically casual medium, he says there's a trade-off: "a certain amount of diversity and creativity that suffers as a result of that transition."
WHAT'S ON OFFER?
Some podcasts, like that of Seed magazine, offer quick nuggets of information, while the Center for Inquiry's "Point of Inquiry" presents long-form interviews. "NPR: Health and Science" splices together news stories on the topic. Others have a singular focus - existing solely for scientists to respond to proponents of intelligent design or to recount happenings at the San Francisco zoo. For "Science Talk," Mirsky draws discussion topics from Scientific American magazine or current events and tries to liven up his interview format with a feature he calls "Totally Bogus"-listeners guess which of the four science news clips he reports is fake.
Chris Smith's Nature podcast relies on punning and "getting scientists to tell the story in their own words." On the radio program-turned-podcast "The Naked Scientists" which he also produces, Smith says outer space is the most popular topic by far, while within the life sciences, stem cell news gets the most attention.
For scientists with limited time, the specialization of science podcasts is a big draw. "If it comes down to watching a 30 minute news program that may have a few minutes of something of interest, or listening to a 30 minute science podcast that's directly on point, it's 'òGoodbye, Dan Rather,'" Leyden says. "Being able to download a podcast that [can] pull together all the stories from a week, it's a very efficient use of time," says Scientific American's Rennie. That's even more true if listeners use the fast-forward function, says Jason Ptacek, a graduate student in molecular biophysics and biochemistry at Yale University.
The talent of the podcaster plays a major role in the popularity of podcasts, and respondents to The Scientist's survey say they consider the host's science know-how more important than his or her voice quality and rank it well above a sense of humor. Still, a monotonous host can kill the experience for a listener. To do the job right, "it takes a little bit of skill, a little bit of understanding of the field," says Smith. "It's a learning curve."
The podcasts of Science, Nature, and NPR's "Science Friday" often play in the background in Ptacek's lab. "We don't like each other's music, but we can all agree on science podcasts," he says. He listens while setting up protein microarrays. "Podcasts don't require as much energy as reading," he says, "but at the same time I get broader knowledge of what's going on in science."
And the more conversational format allows scientists easy access to fields outside their own, says Donald Kennedy, editor-in-chief of Science. "How many inorganic chemists understand a paper in astronomy, how many molecular biologists understand a spintronics paper?" he asks. "There is a lot to be gained by expanding the envelope of scientists understanding one another."
"Podcasts can serve to enhance enthusiasm, to point out topics you want to go into a little further," says Leach. "It's sort of like an ad for things you want to look into deeper."
The ability to download the podcast of a radio program rather than blocking out time to listen to it when it's broadcast is another advantage. For St. Louis University's Cox, that's what makes the difference between listening and not listening to NPR's "Science Friday." Her other option, downloading such radio shows on a website like audible.com, would cost up to $45 for a year-long subscription. "Science Friday," like all other podcasts, is free.
Jamie Cope heard about podcasts early on from his "geek friends." He listens to science ones while biking to work at the pharmaceutical company Ilypsa, where he leads the biochemistry and molecular sciences group. Once he arrives, he likes to advocate the medium at the water cooler. Cope says he misses the "days when I had enough time to sit in library and pick up a copy of Nature, Science, et cetera. This is the only way I find out about current [science news]."
But Nature's podcast is "designed to complement the journal, not replace it," says Timo Hannay, director of web publishing at Nature. "I hope it gives readers an additional perspective they can't get from print journal or online."
For programs like "Science Friday" and "Quirks and Quarks" that already exist on the radio, the format exponentially increases its distribution at little cost. The "Science and Society" radio show, which Lemberg co-hosts and executive produces, has been on the internet for nearly four years. As soon as he began offering a podcast format a year ago-allowing listeners to hear the content at their convenience-their already international audience jumped from 10,000 to 60,000 per month. As for "The Naked Scientists" radio show, Smith estimates that podcast subscribers, as opposed to live listeners, easily make up "a good third to half of our audience [of 160,000] each week" and its fan base now ranges from Texas to Iraq to Croatia. According to Kirsten Sanford, "This Week in Science" is now heard in more than 80 countries.
Podcast listeners are more likely to be male, according to The Scientist's survey: 58% of male respondents said they listen to podcasts, compared to 38% of women who responded. There is no difference, however, in the average age of podcast listeners and non-podcast listeners.
NOT EVERYONE'S CUP OF TEA
Podcasts haven't caught on with everybody. Frances Burton was disappointed last year when she opened up a science podcast for the first and only time. From a "prestigious journal" like Nature, the University of Toronto professor of anthropology emeritus expected "credibility and function directed at scientists," but got something that was "terribly entertainment-like." Hannay acknowledges that the Nature podcast has lighter fare, "more digestible content than the journal itself. But it has to be, to be true to the audio form," he says.
The most common reasons our survey respondents cited for not listening were that they didn't have an mp3 player, they found podcasts too long, and thought they were usually written for a less-informed audience.
And podcasts may never convert a generation of scientists used to holding journals in their hands. "I loathe to take time to hear a podcast when I could read that information, or skim it," Burton says. "You can't skim a podcast." Howard Mount, a neurobiologist at the University of Toronto and a self-described "technophobe," prefers to "flip through a table of contents really fast [or] read abstracts."
SO WHAT'S NEXT?
So what does the future hold for science podcasts? For one thing, it will become easier to find the good ones, an issue cited by several of our survey respondents. "I think it's exactly the same way the internet evolved ten years ago, [when] search engines came in and were able to separate wheat from chaff," says Smith.
Lemberg says videocasting is "just the next transition." That could assuage the concerns of scientists like Mount, who says "there's a laudable 'show me the data' skepticism in science that is not easily satisfied by the podcast format." Podcasts like those from Nature and MicrobeWorld already use videocasting occasionally, and the National Institutes of Health regularly offers events, seminars, and lecture series on the medium, but according to Mirsky, they are still "way more complicated" and costly than their audio counterparts.