Piece of the week: “In the eery silence that followed Mary Stastch quietly strangled her infant.” Eric Michael Johnson has a superb piece in Scientific American on why mothers kill their kids. David Dobbs has an insightful reply too.

Coolest story of the week: here’s a guy who uses electric fish to make music. The best bit about this is that it was posted at Discover’s Science Not Fiction blog, just hours after I posted my piece on electric fish. And my post was about convergence, where two species evolve the same traits independently of one another!

Strange deaths have been linked to unregulated stem-cell therapies. “The latest cases highlight the difficulty of policing these therapies or