that is, beneficial to the survival of the animal. For example, increases in corticosteroid levels promote mobilization of energy, important in times of need. Corticosteroids also inhibit systems that channel resources to functions such as growth and reproduction, not necessarily of value in the midst of physiologic challenge. Similarly, behavioral changes seen during chronic stress, while at first blush “pathological,” can be argued to be beneficial in the context of chronic challenge. For example, post-stress reductions in risk assessment/behavioral withdrawal seen in so-called “anxiety” tests (e.g., elevated plus maze) (e.g., see Chiba et al., 2012) minimize risk during periods of energetic challenge. Minimizing risk may also be linked to the switch to “habitual” behaviors observed in chronically stress rodents (e.g., see Dias-Ferreira et al., 2009; Harris et al., 2012). In a hostile environment, it may make sense to exhibit behavioral withdrawal in order to reduce threat (i.e., make oneself less available for predation). Even observed changes in immobility in the forced swim test, commonly linked to depressive phenotypes, may be interpreted as a means of conserving resources during challenging times (see Hawkins et al., 1978). Thus, while responses to chronic stress can clearly have negative consequences, one has to consider
