Highly technical scientific debates are usually hashed out behind closed doors—in labs, in subscription-based journals, in the hallways at conferences attended only by a few specialized researchers. But in May the rest of us saw three real academic arguments playing out in public, largely via Twitter, blogs and wikis. The episodes have cheered supporters of the open-science movement, but some critics worry that the debates might descend into cacophony. Either way, the stories illustrate one clear fact: science is not usually a series of eureka moments so much as a messy, human process.

First, there was “#arseniclife,” which began with a controversial study, first published in the online version of Science, suggesting that some bacteria could build DNA with arsenate in place of phosphate. Scientists quickly tried to poke holes in the researchers’ methods via blogs and Twitter (hence the controversy’s nickname, taken from the practice of categorizing tweets with hash tags), and the debate bounced back into the print version of Science, which took the unusual step of publishing eight sharp critiques of its own paper in May. Meanwhile at Nature standard peer review had also taken an unusually public turn. Reviewers almost always keep their identities under wraps, but one outed himself online, saying he had been “desperately upset” when the journal  published a paper about extinction rates that he had criticized.

Also in May, Nature Genetics published online the results of its own experiment in open scientific debate. A team of researchers writing a paper on best practices for following up on new biological hypotheses coming out of genomics solicited opinions in an online forum. The scientists also threw the writing process open on WikiGenes, a collaborative Web site. Did the experiment succeed? Nature Genetics seemed pleased: it published an editorial noting that the conversation had been so thorough that publication could proceed “without further need for supervised peer review.” But one contributor, a graduate student named Giovanni Marco Dall’Olio, had a quibble: “They did not include almost anything from what has been contributed in the wiki.” He wrote that criticism, of course, on his blog.