exogenous zeitgebers

• what is an exogenous zeitgeber?

  External cue that synchronizes an organism's biological rhythms
• what are some examples of exogenous zeitgebers?

  light, temperature and social cues
• how does light work as an endogenous zeitgeber?

  it resets the biological clock everyday to match the outside world
• how do social cues work as an endogenous zeitgeber?

  things like mealtimes and bedtimes help with keeping the circadian rhythm in check