These are just averages, though. According to The New Teenage Body Book, “each person has his or her own special biological time clock that dictates when the various changes of puberty will occur. ”
Raamatu „The New Teenage Body Book ” sõnul„ on igal inimesel oma bioloogiline kell, mis dikteerib seda, millal organismis erisugused muutused aset leiavad ”.