Timing Responses

Annular cycle- 365 days, 12 months, 52 wed. → Seasonal Changes (Temperatures, Weather…)

Daily Cycle- 24 Hours →Day/Night (Light/Days)

Tidal Cycle- ~12hours → High/Low Tides (i.e. Water level)

Lunar Cycle- 28 Days/4 Weeks → Phases of moon, Light changes → Full moon vs New Moon

Annual Rythm - Circannual

Daily Rythm - Circadian

Tidal Rythm - Cirratidal

Lunar Rythm - Cirralunar

Nocturnal → Night

Diurnal → Day

Crepuscular → Sunrise/Sundown

Exogenous =

Endogenous

Rhythm is maintned by internal conditions → persists in the absence of external stimuli

Free running period → the time of the cycle (E.g. sleep wake) in the absense of external stimuli

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Zeitgebert → the external stimulus that resets the endogenous rhythm/internal biological clock.

e.g. light resets human sleep/wake cycle

Adaptive adaptive → allows animals to respond approritaley to changes in the environment

e.g. Jet Lag, Seasonal Changes, Day & Night lengths ect.

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Mammalian Endogenous Clock

To start calucations, start from the day where the change occurs. Calculate change in hours → from the 1st day of free running period to another day.

e.g. Day 6 (1st day) - Day 19 (last day)

Divide # hours by # of days.

e.g. 7 Hours/14 Days = 0.5 hours.

Add shift to 24 hours (cirrcadian rythm) when graph/activity shift RIGHT. OR 12 Hours (qirratidial rythm)

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To find the time o f the internal biological click → add shift + rythm oeruid e.g. Carrcadian = 24 Circatidal = 12

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Our own Biological clock is 25.5 hours.