Fear of new things shortens life: “Animals with an innate phobia of novelty have higher levels of stress hormones after a new experience and die significantly younger than their braver kin, new research has found. The work suggests that a lifetime of fearful stress can take an accumulated toll on health.” —New Scientist Evolutionarily, though, would it not make sense that tolerating higher levels of stress better would be selected for, given the obvious survival value it confers? It is not clear that the health effects of stress on a lab animal bred specifically to be stress- or novelty-intolerant can be generalized to “a lifetime of fearful stress” in an evolutionarily equipped organism. Furthermore, might the study results be turned on their head — one might imagine that it may not be that fearful animals die younger than braver kin, but rather that animals who (for some undiscovered constitutional reason) are going to die younger are more fearful than their kin. As usual, correlation is not necessarily causation. In any case, go out there and try a new thing or two…