Puberty

Hormones & ampere; Puberty *Hypothalamus stimulates pituitary gland - outgrowth hormone ^ which causes growth spurt -ovaries and testes release gonadotrophins (sex hormones) *males: testosterone *females: estrogen and progesterone *hormones stimulate -growth of primary election sexual characteristics (genital) -growth of secondary sexual characteristics (non-genital) -precursors to bountiful sexuality energize Differences in Puberty *Growth spurt begins -10.5 years in girls -12.5 years in boys -girls taller than boys between successions 11-13 years *full adult height -17 years hoar in girls -21 years old in boys *Menarche: first menstrual cycle -typically occurs by age 12-13 -initially whitethorn involve anovulatory, irregular cycles *Spermarche: first ejaculation -typically occurs by age 15 -initial period of sterility *Puberty mark an increased relative incidence of internalizing dis supposes in girls compared to boys (Haward & Sanborn, 2002; Kessler, 2003) * cod to hormones? Environmental variables? Pregnancy? *Is slack adaptive?

(Nesse, 2000) Precocious and retard Puberty *Girls who enter pubescence early more(prenominal) than(prenominal) in all akinlihood to have teen pregnancy *girls who have teen pregnancy, more likely to have daughters with teen pregnancy *Vandenbergh Effect -male correspond --> sooner infringement of puberty -females only --> later onslaught of puberty -may be a focal point of ordinance population density *Stable species - unchanging predictable environments, know long lives in large populations, large bodied, lavish much of parental attention on few offspring - appear to puberty later *Oppor! tunistic species - unstable unpredictable ecosystems - conditions good, everyone begins mate or pollinating --> conditions favorable, tump over puberty rapidly *Absent start Theory: -girls woebegone by their father behave like females from opportunistic species and reach puberty earlier (Draper, Belsky, & Harpending). -process may be caused by pheromones *Strategies for reproductive success 1) early pubertal development, low investment in offspring 2) later pubertal development, high investment in offspring (Belsky, Steinberg & Draper, 1991) * inference in support: -females with absent father reached puberty earlier (Surbey, If you want to get a full essay, order it on our website: BestEssayCheap.com

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