Synchronization

Chris Jernigan andDanielle Edgeworth

What is Synchronization?

• timekeeping which requires the coordination of events to operate a system in unison

•oscillators fire at an accelerated rate until all are firing

(Strogatz)

How Synchrony Occurs

•A threshold exists at which an event occurs

•The event is sensitive to similar event in it’s surroundings▫Positive feedback, negative feedback, or

alteration completely

(Strogatz)

Fireflies flashing•Synchronization is observed to occur in

some species of fireflies

(Strogatz)

(Nature.com)

Fireflies: How and Why?•How do they synchronize?

▫Want to be the first to flash? synchrony▫Feedback Positive or negative Alters rate and

thus leads to synchrony

•Why would they want to synchronize? Why would this evolve?▫Attract mates to one location difficult to find a

mate in a thick forest when all you have is a glowing abdomen

▫Trick a partner trying to mate with your neighbor?

(Strogatz)

Cardiac Pacemakers•each oscillator

rises toward threshold until the result is synchronized

(Strogatz)

Crickets•Similar to fireflies,

one cricket will start it’s chirp and before long there will be a chorus of chirps

•Though the do not have a “flash-control pacemaker”

(Strogatz)

Sleep/daily Life

(Strogatz)

Circadian cycle

•“Biological clock”

•zombie zone•forbidden

zone•nap phase

(Strogatz)

Women and Menstrual Cycles•Women who are very close seem to sync

their menstrual cycles

Run! They’ve synchronized!

(Strogatz)

Women: How and Why?

•How do they synchronize or adapt to one another’s menstrual cycles?▫In various studies have shown that sweat

some kind of chemical signal that alters menstrual cycles

• Why would it be beneficial for this to evolve?▫Co-care of offspring?

Care if mother were to die…. etc…

(Strogatz)

References

•Mirollo, R.E. and Strogatz S.H. 1990. Synchronization of Pulse-Coupled Biological Oscillators. SIAM J. Appl. Math. 40(6). P 1645-1662

•Strogatz, S. Living Sync.