Intergenerational effects of maternal androgens on vocal ontogeny and developmental plasticity in a cooperatively...

Developmental plasticity, the ability to adapt one's phenotype to environmental cues, is crucial during early-life stages and can affect fitness. Despite significant androgenic variation between females of select species, the impact of maternal hormones on offspring ontogeny in wild mammals has been rarely investigated. Here, we rely on natural and experimentally induced variation in androgen action between dominant and subordinate female meerkats, Suricata suricatta, to examine plasticity of vocal development in their offspring. Meerkats are cooperatively breeding mongooses that have a rich vocal repertoire. We recorded calls produced at distinct developmental stages by offspring from dominant and subordinate control mothers that naturally differ in absolute androgen concentrations and from dominant treated mothers that had received an androgen-receptor blocker in late gestation. Using call types as indicators, we found that the offspring of dominant control mothers had a robust vocal trajectory, even under adverse environmental conditions; following full nutritional dependence, their vocal development was accelerated relative to that of other offspring. Conversely, offspring from both subordinate control and dominant antiandrogen treated mothers suffered ontogenetic delays; they showed distinct sex differences in trajectory and a greater sensitivity to socio-ecological influences. Antiandrogen-exposed offspring also showed atypical early call usage. These findings provide rare evidence of the potential for maternal androgens to mediate mammalian offspring development in accordance with demands of the socio-ecological environment.