Abstract

Living organisms are caught between a hammer and an anvil, evolutionarily speaking. On the one hand, they need to buffer the influences of genetic mutations and environmental stresses if they are to develop normally and maintain a coherent and functional form. On the other, stabiliz- ing one’s development too much may mean not being able to respond at all to changes in the environment and starting down the primrose path to extinction. On page 618 of this issue, Queitsch et al.1 propose that, in plants, the balance between stability and the potential for change is made possible in part through a protein involved in ‘heat- shock responses’ in a wide variety of species, from plants to insects.