This month's feature article by Kate Wong, "Lucy's Baby," represents something both very old and very new. The old has been christened Selam, a tiny being who was born 3.3 million years ago but did not live past her third birthday. Contrary to the nickname by which she has also come to be well known, Selam was most definitely not a child of Lucy, the Australopithecus afarensis female whose skeleton was famously unearthed in 1974--Selam predated Lucy by more than 100,000 years. (Yet incongruity trumps chronology: it seems equally wrong to refer to a baby as "Lucy's grand¿mother.") Those two australpithecines were probably about as distantly related as any one of us is to the first modern humans to spread out from Africa.

But Selam and Lucy are kin as grande dames in the scientific reconstruction of how humans came to walk. Decades ago paleoanthropologists argued about whether our ancient ancestors evolved large brains and then walked erect or became bipedal before they were brainy. The discovery of upright but small-skulled Lucy helped to settle the matter decisively. Now Selam is further illuminating whether A. afarensis spent all its time on the ground or, like an ape, still lived a partially arboreal life, as Wong describes, starting on page 78.

So much for the old. What's new about the article is the experimental nature of how it came to be.

The discovery of Selam jumped into headlines around the world this past September. Such momentous, fast-breaking stories can be the bane of monthly print magazines because long publication lead times dictated that we would not be able to share the story with our print readers in any detail until our December issue--an eternity in the 24/7 universe of modern media.

We therefore decided to launch an experiment that we had been contemplating for some time. Kate Wong immediately wrote a news story and posted it on Scientific American's Web site to coincide with the Selam announcement. But that post also invited readers to send us questions and comments, pointing out how they would like to see this story expanded for print. Wong also solicited remarks from leading paleoanthropologists and continued her own reporting.

Thus, Scientific American's coverage of Selam has continued to grow and evolve right up through the December issue deadlines--and will continue to grow after this page goes to press. Distilled into the print version is the best of what has come from this publishing experiment, but we encourage anyone who wants to explore those contents more fully to go to www.sciam.com/ontheweb.

Digital media are already revolutionizing many parts of the publishing industry. Physicists have been sharing preprints of their papers online for more than a decade; now even the professional journals are testing digitally enabled alternatives to traditional peer review. Wikis, social bookmarking and other online exercises in communal authorship have opened eyes to novel ways of creating quality content. We relish the possibilities of this new approach to publication and expect to do much more of it in future issues of Scientific American. In the meantime, please tell us what you think about it, too. Your feedback, after all, is what makes this idea work.

This article was originally published with the title Old Baby in the New Media.

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