Abstract

The placenta arose during mammalian evolution, which is recent in evolutionary terms. Genetic changes underlying placental development remain identifiable by the new science of comparative genomics (approximately post‐2000). Randomly arising features of genomes including endogenous retroviruses and transposable elements have provided structural genes and gene‐regulatory motifs responsible for innovations in placental biology. Stochastic genetic events indeed contribute to new functionality. Theologically, random mutations are part of the strategy by which the divine purpose for humanity is attained. Placental function critically underlies human brain development, and suboptimal function, associated with environmental conditions and maternal distress, contributes to mental health deficits in the offspring. Many enter life with handicaps arising from contingent events in utero, mandating understanding, compassion, and socioemotional support, imperatives native to moral including biblical values. The extended period of development afforded by placentation enables prenatal parenting, with implications for sensitive and devoted parental commitment.