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Natural time – Part 2


 / AFP PHOTO / Frederic J. BROWN

/ AFP PHOTO / Frederic J. BROWN

Fortunately, the blood women shed each month is usually their own. (But unchecked feminism may soon change this—as male users of ATM are all-too aware!).

Nevertheless, the menstrual flow of females is, in many respects, a metaphor of power—a periodic occurrence, whose rhythmic pattern is linked to the availability of moonlight.

Biologists call this “lunar phase locking”. Winnifred B. Cutler (U.S. Athena Institute) defines phase locking as “a synchronous relationship between the menstrual cycle and lunar rhythm”.


As earlier noted, the Moon’s orbital period gives rise to the month–one of three fundamental units of time, as experienced from the surface of our planet.

The time it takes, for the Moon to make one trip around Earth, is actually 27.3 days. But changes in its visual appearance, from new moon-to-new moon, occur in 29.5-day cycles.

In the meantime, the menstrual cycles of some higher female primates—particularly humans, gorillas and orang-utangs—are very close to that of the synodic lunar period.

It averages 28 days for humans and–says Ronald D. Nadler, of Yerkes Regional Primate Research Center, Emory University, Atlanta–about 29 for orang-utangs and 30 for gorillas.

Not everyone accepts the phase-locking hypothesis. Among the doubters is Wikipedia, which shrugs off the close relationship between the human and lunar cycles as a “coincidence”.

But Cutler and her camp are undaunted. Writing in the journal Human Biology, she and her co-authors report empirical evidence, which, they insist, support lunar phase locking.

“We hypothesize,” we they asserted, “that a systematic relationship between day of the lunar cycle and density of menses onsets might exist”.

They cite the work of other researchers, which have “clearly shown that women whose cycles approach the 29.5 day span have the highest likelihood of fertile cycles”.

By contrast, they continue, “women whose cycles become longer or shorter have a proportionately diminishing incidence of fertile cycles”.

Elsewhere, Cutler presents the results of an empirical study of 312 university students, who kept records of their menstrual cycles—68 of which experienced lunar cycles of 29.5 days.

She and other investigators (who generally do not rule out coincidence) have speculated on several “exogenous” influences that could account for the synergy between menstruation and lunation.

“One possible explanation,” she wrote, “is that a natural rhythm of electromagnetic radiation has its origin in the lunar cycle and may be reflected in phase-locking of the human menstrual cycle”.

Other often postulated influences; include pheromones, gravitational influences and evolutionary behavior patterns, based on the availability of light.

The changing angle of the Moon’s illuminated half, to an observer standing on Earth’s darkened hemisphere, is what accounts for the succession of phases, over the course of a month

U.S. historian, Eugenia W. Herbert notes that the menstrual cycle of women and the dependability of the Moon’s recurring luminous configurations, have deeply imprinted African anthropology.

This periodicity, she observes, in “Iron, Gender, and Power: Rituals of Transformation in African Societies” (a study of pre-Colonial iron industries), is seen as “oscillation between order and disorder”.

The power African cultures attribute to menstrual blood, Herbert argues, has its origin in their perception of lunar periodicity.

Contends she: ”The menstrual cycle is characterized by such periodicity, signifying both fertility, that is potential for life, and waste or… the loss of… life”.

Hence the fertility of the smelting furnace, is equated with conception, while the failure of an ore charge to yield usable iron, is envisioned as the “discharge of blood”.

• To be continued.

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