Schmidtea happens: Re-establishing the planarian as a model for studying the mechanisms of regeneration

Understanding the remarkable regenerative abilities of freshwater planarians was a classic
problem of developmental biology. These animals were widely studied until the late
1960s, when their use as experimental subjects declined precipitously after some infamous
experiments on memory transfer. By the mid-1990s, only a handful of laboratories
worldwide were investigating the mechanisms of planarian regeneration. Here, we provide
the personal stories behind our work to reinvigorate studies of these fascinating
animals. We recount many of the challenges that had to be overcome and reflect on
some of the fortuitous events that helped launch the planarian Schmidtea mediterranea
as a model organism for studying the molecular basis of regeneration.