Depression for Surviving Ancestral Hardships

Although researchers have attempted to explain depression as an evolutionary adaptation, those prior attempts have been incomplete at explaining the phenomena and ineffective at providing treatment tools. The discussion provided here attempts to improve the theory and point to effective tools. Depression dims hope and leads to a reduction in most non-essential human behaviors: sexual interest fades, and pleasurable activities can lose their appeal. A clinical diagnosis of depression can persist for weeks, months, and sometimes even years. I theorize that depression evolved due to recurring ancestral hardship situations that involved elevated risks of subsequent starvation and other dangers. Depression evolved to enable humans to survive the social forager’s hardships. Depression can be considered a counterpart to the hunger adaptation for long-term survival since nutritional calories were precious and not to be misspent unproductively. Evidence to support this theory of depression is provided based on situations that trigger depression and a general understanding of how hunter-gatherers manage risks individually and cooperatively. This theory may also explain some other puzzling observations associated with depression: the connections among hoarding, depression, infertility, and immunosuppression, why depression occurs in the peripartum period and following the death of a loved one, the anxiety that depressed people often feel, why depression persists for extended periods, and the remarkable physiological similarities between depression in humans and animal hibernation. Recommendations for treating people with depression are to make them healthy, well-fed, productive, and valued by others.