> empathy in killing an offspring who’s not their own
As well as their own: "numerous studies support the correlation between postpartum depression (PPD) and lack of social support or indicators of possible infant health and development problems. PPD may be an adaptation that informs mothers that they are suffering or have suffered a fitness cost, which motivates them to reduce or eliminate investment in offspring under certain circumstances, and that may help them negotiate greater levels of investment from other [1].
More broadly, "the analytical rumination (AR) hypothesis proposes that depression is an adaptation that evolved as a response to complex problems and whose function is to minimize disruption of rumination and sustain analysis of complex problems" [2].
As well as their own: "numerous studies support the correlation between postpartum depression (PPD) and lack of social support or indicators of possible infant health and development problems. PPD may be an adaptation that informs mothers that they are suffering or have suffered a fitness cost, which motivates them to reduce or eliminate investment in offspring under certain circumstances, and that may help them negotiate greater levels of investment from other [1].
More broadly, "the analytical rumination (AR) hypothesis proposes that depression is an adaptation that evolved as a response to complex problems and whose function is to minimize disruption of rumination and sustain analysis of complex problems" [2].
[1] https://anthro.vancouver.wsu.edu/documents/316/Hagen_1999_Th...
[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC2734449/