Non‐human primates avoid the detrimental effects of prenatal androgen exposure in mixed‐sex litters: combined demographic, behavioral, and genetic analyses

We examined whether neonatal testosterone exposure might be detrimental to females in mixed‐sex litters by compiling data from long‐term breeding records for seven primate species (Saguinus oedipus; Varecia variegata, Varecia rubra, Microcebus murinis, Mirza coquereli, Cheirogaleus medius, Galago moholi). Litter sex ratios did not differ from the expected 1:2:1 (MM:MF:FF for twins) and 1:2:2:1 (MMM:MMF:MFF:FFF for triplets). Measures of reproductive success, including female survivorship, offspring‐survivorship, and inter‐birth interval, did not differ between females born in mixed‐sex versus all‐female litters, indicating that litter‐producing non‐human primates, unlike humans and rodents, show no signs of detrimental effects from androgen exposure in mixed sex litters. Although we found no evidence for CYP19A1 gene duplications—a hypothesized mechanism for coping with androgen exposure—aromatase protein evolution shows patterns of convergence among litter‐producing taxa. That some primates have effectively found a way to circumvent a major cost of multiple births has implications for understanding variation in litter size and life history strategies across mammals.
Source: American Journal of Primatology - Category: Psychiatry & Psychology Authors: Tags: Research Article Source Type: research