<p>Stem-cell scientists are caught up in fictional friend network — but no-one knows why.</p>
<p>In September 2008, Forbes science editor Matthew Herper and former Washington Post reporter Rick Weiss appeared together on a panel at the World Stem Cell Summit in Madison, Wisconsin. In late February, Herper received an invitation to 'friend' Weiss on the Internet social-networking site Facebook. On the basis of their acquaintance, Herper accepted, noticing that a number of other people involved with stem cells were listed as friends on Weiss's profile. However, that profile — and many of those it was linked to — was a fake.</p>