The Timing of Sexual Maturation among Males in Baduy People, Kanekes Village

Abstract

Puberty is a complex process involving physical and psychological changes, leading to sexual maturation (menarche in females, spermarche in males). This is characterized by secondary sexual characteristics’ emergence. In males, it is marked by testicular enlargement, laryngeal prominences development, body hair growth, and voice breaking. Variations of sexual maturation age may reflect an adaptation to life history strategies in response to environmental constraints and energy availability. Unavailable data on sexual maturation in Baduy males makes it crucial for life history strategy research. This research was conducted in Baduy Luar from November 2022-February 2023. The study involved 180 subjects aged 6 to 30 years (median: 16.00±0.64 years). It showed that balig (13.11±0.249 years) is an important moment in Baduy males as it serves as a social indicator of their puberty. Subsequently, the sequence of secondary sexual characteristics includes voice breaking (13.36±0.270 years), facial hair growth (14.16±0.323 years), spermarche (15.21±0.261 years), and axillary hair (16.44±0.313 years). Baduy males demonstrate a slow life strategy as an adaptive response to their bioculture (high physical activity and different dietary lifestyles), resulting in energetic constraints. This condition indicates an energy allocation trade-off between growth completion and sexual maturation timing, potentially explaining the older age of their spermarche.