Circadian Rhythm
Internal biological cycles with approximately 24-hour periods that regulate sleep, metabolism, hormone release, and many other functions. The body's internal clock.
Used in the Books
This term appears in 3 chapters:
"...ime-based constraints: when to launch products, when to scale teams, how to coordinate across time zones, when markets are "in season." Chapter 8: Circadian Rhythms explores the economics of time - how biological clocks optimize survival by synchronizing behavior to predictable cycles, and what this teaches us ..."
"...tire populations spanning hundreds of miles. No alarm clock. No external cue triggering the opening. The flower has an internal biological clock - a circadian rhythm - that anticipates dawn with precision measured in minutes, not hours. The timing is not random. Opening at 4 AM allows the flower to be fully bloom..."
"...nisms. Daily cycles (24 hours): Temperature, light, humidity fluctuate between day and night - Driven by Earth's rotation - Organisms adapt with circadian rhythms (sleep-wake cycles, photosynthesis timing) - Predictable and experienced by all individuals Seasonal cycles (annual): Temperature, precipitation..."
Biological Context
Circadian rhythms are endogenous—they persist even without environmental cues—but are normally synchronized (entrained) to light-dark cycles. The suprachiasmatic nucleus in the brain serves as the master clock. Disruption causes jet lag, metabolic problems, and increased disease risk.
Business Application
Organizations have rhythms too: quarterly planning, annual reviews, daily standups. Aligning work to natural rhythms improves performance; fighting them causes organizational jet lag.