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. 2009 Jun 17;31(4):276–284. doi: 10.1159/000216538

Table 1.

A delay in circadian phase has been observed around the time of puberty in six mammalian species

Species
human (Homo sapiens) rhesus monkey (Macaca mulatta) degu (Octodon degus) laboratory rat (Rattus norvegicus) laboratory mouse (Mus musculus) fat sand rat (Psammomys obesus)
Magnitude of delay 1–3 h 2 h 3–5 h 1–4 h 1 h? 0–3 h under a long photoperiod, 10–14 h under a short photoperiod

Sex difference males > females only females examined males > females males > females only females examined sex unspecified

Rhythms delayed sleep, melatonin activity activity, sleep? activity activity, corticosterone, temperature? oxygen consumption, temperature

No. of experiments >20 1 6 4 2 1

Age of peak delay 15–21 years 39 months 80–100 days 30–40 days unknown, but delay evident at 35–45 days unknown, but delay evident at 35–42 days

Age of establishing overt cyclicity in females menarche: 12–13 years regular ovulation: 13–16 years [21] menarche: 30–33 months first ovulation: 42–45 months [12] cycles in vaginal opening: 35–150 days [13, 16] first ovulation: 35–45 days [22] first ovulation: 27–40 days regular ovulation: 30–80 days [23, 24] unknown

Age of establishing spermatogenesis 12–16 years [21] n/a 60–120 days [13] 45–65 days [22] n/a 28–56 days [25]

Gonadal dependent maybe unknown maybe maybe unknown unknown

Circadian citations reviewed in [4, 8] [12] [13, 14, 15, 16] [16, 17] [18, 19] [20]