Figure 2.

The concept of the return to prepubertal growth velocity curve as a life history mile stone. Here, we define the return to take-off velocity as the transition from adolescence to emerging adulthood. (A) Schematic representation of the age-dependent pubertal take-off velocity and the return to prepubertal growth velocity curve; in girls the return to takeoff velocity coincides with menarcheal age in the early, average, and late maturers. The age-dependent decline in peak height velocity is a function of the decelerating takeoff velocity and returns to the prepubertal growth velocity curve. PGV, peak growth velocity; TV, takeoff velocity; RTV, return to prepubertal growth velocity curve. (B) The age of return to prepubertal growth velocity curve as a function of adult body mass in 21 primate species. Observations are derived from captive primates held at zoological parks and primate centers. With permission from Leigh and Park (42). a—Cebus apella, b—Cercopithecus aethiops, c—Cercopithecus mitis, d—Cercopithecus neglectus, e—Erythrocebus patas, f—Cercocebus atys, g—Macaca arctoides, h—Macaca fascicularis, i—Macaca fuscata, j—Macaca mulatta, k—Macaca nemestrina, l—Macaca silenus, m—Papio hamadryas, n—Mandrillus sphinx, o—Colobus guereza, p—Presbytis entellus, q—Presbytis obscura, r—Gorilla gorilla, s—Pan paniscus, t—Pan troglodytes. (C,D)—average adult body weight as a function of the age at return to prepubertal takeoff growth velocity of males (C) and females (D) in six predeveloped societies. Data from http://dice.missouri.edu.