Arsenic and the structure of scientific communication
NASA announced a press conference about a new discovery in extraterrestrial life, leading to wild and incorrect speculation by weblogs and the media about what they had found. After the actual paper was published in a peer-reviewed scientific journal about bacteria which were said to incorporate arsenic into their DNA, critics of the paper appeared in science weblogs calling into question the science and its research methods.
Here's a small look at the science involved, and a broader look at how it was communicated to the world. Noteworthy in this storytelling is an effort by the UK newspaper The Guardian to escape the newspaper story format for scientific reporting and look at a new "story tracker" narrative to collect reactions and updates days and weeks after the initial story broke as news.
NASA: the news embargo, the press conference, and the peer reviewed journal
Under the hyperbolic headline Has NASA discovered extraterrestrial life?, news of a forthcoming NASA press conference was shared by blogger Jason Kottke. The release announced an "astrobiology finding that will impact the search for evidence of extraterrestrial life." Speculation about the nature of this discovery started promptly, in the absence of any more detail than the names of the principal investigators, with curiosity about the discovery of life on Saturn's moon Titan.
Ivan Oransky's weblog Embargo Watch keeps an eye on how scientific information embargoes affect news coverage. An embargo is an agreement between news organizations to keep information secret until a scheduled publication time. Not every news organization and journalist adheres to these handshake agreements, and the existence of this temporary secrecy leads to all kinds of wild speculation. Enterprising reporters who don't have access to embargoed materials but who instead do old-fashioned reporting can and do write stories that appear to break the embargo, and Oransky's essay Science gets it (mostly) wrong again: My take on the NASA astrobiology paper spells out the confusion, hype and misinformation that comes from the typical embargo process.
The details, when finally released, were less exotic than arsenic-eating bugs on Mars. NASA-Funded Research Discovers Life Built With Toxic Chemical reads the news release, stating that researchers conducting tests in the harsh environment of Mono Lake in California have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The paper, published in Science Magazine, reaches these conclusions:
Life is mostly composed of the elements carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. Although these six elements make up nucleic acids, proteins, and lipids and thus the bulk of living matter, it is theoretically possible that some other elements in the periodic table could serve the same functions. Here, we describe a bacterium, strain GFAJ-1 of the Halomonadaceae, isolated from Mono Lake, California, which substitutes arsenic for phosphorus to sustain its growth. Our data show evidence for arsenate in macromolecules that normally contain phosphate, most notably nucleic acids and proteins. Exchange of one of the major bioelements may have profound evolutionary and geochemical significance.
Most media organizations leave it at that. Scientists Find Arsenic-Eating Bug That Holds Clues to Extraterrestrial Life, writes AOL News, in a story classified under "Weird News".
Science blogging as peer review?
The structure of scientific communications is very formal, with editors, review boards, publication delays, and competition for a few slots in a small number of prestigious journals.
The structure of scientific blogging is free form, with individuals writing their own research blogs, some in organized online communities but nothing like the formalized, institutionalized structure of scientific print journalism. Authors can write without peer review, and comments - including anonymous and pseudonymous comments — have no vetting or prior review for accuracy.
After the publication of the paper, a set of skeptical scientists from a range of fields looked at the results to see how they measured up to their own expertise, either in chemistry, microbiology, or laboratory methods. I was alerted to the post on Dr. Rosie Redfield's blog RRResearch, which has detailed and reasonable critique of the methods uses in the NASA paper, with an alternative explanation for the results which seemed very plausible to this non-expert reader. A dozen or more individuals weighed in, each with aspects of the analysis to revise or (perhaps more tellingly) discussion of how to write up this response as a formal scientific communication, to be reviewed in the same channel that the original was published.
The media and scientific writing
I looked for both good and bad examples of how intelligent science writers were covering this, noting the difficulty of accurately telling a story that unfolds over weeks as a variety of people weigh in with opinon, test and examine assumptions, and explain at a more detailed level the science that is going on that didn't make it into the press-release sized explainer.
This story from the CBC is typical of the better reporting on the criticism. In NASA's arsenic microbe science slammed, the science writer at CBC News tells a very typical news narrative — self contained, comprehensive enough to stand on its own, with quotes from both sides and just enough of an explainer to give the first-time reader enough to stand on. The story will go into the CBC website and get stacked up with thousands of stories that week, a brief slice in time of how the controversy unfolds.
What caught my eye as a better format for telling the complicated process was this ongoing "story tracker" page from The Guardian (UK), which was originally published Dec. 2 as the story first broke and which has been continuously updated, in weblog format, as the news progressed. Nasa dismisses criticism of 'arsenic bacteria' research is the current title, reflecting the most recent commentary from NASA spokesman Dwayne Brown, stating that the author of the paper would not be responding to criticism of the paper in the media but would respond through peer-reviewed journals.
The "story tracker" format was introduced by The Guardian this summer. Editor Alok Jha describes it as follows:
We're trying out a completely new way of covering big science stories. We believe our coverage of a major research paper should not be done-and-dusted with a single story but form part of a continuum. By tracking reactions and analysis from scientists and bloggers over the days and weeks after a news story breaks, we think the coverage of the story will be richer, more informed and more comprehensive.
The additional information in each news update is fragmentary, just a paragraph or three that expands on previous information. If you are really following along, you don't need to go anywhere else other than The Guardian: As news accumulates they put it together with the paragraph at the top that qualifies as news and the ongoing saga below, to dig into as deep as you need to. News fragments that would not qualify as news in their own right can get incorporated into an ongoing narrative, leaving space for comprehensive discussion of something that would otherwise be told one breaking story at a time.
Edward Vielmetti welcomes our arsenic-eating friends to AnnArbor.com.