Neurogenesis (the birth of new neurons from stem cells) is very limited in the adult brain but contributes to highly specific brain functions—most notably, learning and memory. Thus far, its contribution to other brain functions has been less clear. On page 958 of this issue, Chaker et al. (1) report that in mice, pregnancy elicits transient waves of neurogenesis in specific subsections of the subventricular zone (SVZ), the neurogenic zone that produces new interneurons for the olfactory bulb throughout life. These subsections were barely neurogenic in the absence of pregnancy. Once in the olfactory bulb, the newborn neurons contributed to the recognition of the young mice by smell. The data make a compelling case for how adult neurogenesis in the olfactory bulb contributes to an important brain function beyond learning and memory.