Sexual Maturity and Puberty Differences

Sexual Maturity

• Defined as the capability of an organism to reproduce.
• Distinction between sexual maturity and adulthood; influenced by cultural definitions.

Developmental Timeline

• Most multicellular organisms become sexually mature well after birth; duration varies by species.
• Cues for sexual maturity: external (e.g., drought) and internal (e.g., body fat percentage).

Physiological Changes

• Sexual maturity involves maturation of reproductive organs and gamete production.
• Accompanied by physical changes known as secondary sex characteristics; indicate sexual dimorphism.

Infertility and Sex Change

• Post-maturity, some organisms may become infertile or change sex.
• Progenesis: rapid sexual development compared to other physiological development; retains juvenile characteristics.

Puberty Differences

• Girls typically begin puberty at ages 10-11, completing by ages 15-17.
• Boys start at ages 11-12, complete by ages 16-17.
• Girls attain reproductive maturity 4 years post-physical changes; boys develop slower and grow longer.

Hormonal Influences

• In boys, testosterone is the principal sex hormone, driving virilization and the male growth spurt.
• Girls’ development is influenced by estradiol; it promotes breast and uterus growth, and governs the growth spurt.

Height Differences

• Before puberty, girls are slightly taller; adult men average 13 cm taller than women.
• Differences attributed to growth spurts and estradiol levels.

Complex Female Hormonal Maturation

• Estradiol rises earlier and is present in higher levels in females.
• Female pubertal hormonal processes involve testosterone, estradiol, progesterone, and prolactin; conversion rates vary individually.