Lunar effect
Coral species such as Dipsastraea speciosa tend to synchronize spawning in the evening or night, around the last quarter moon of the lunar cycle.
[6][7][8] Claims of a lunar connection have appeared in the following contexts: It is widely believed that the Moon has a relationship with fertility due to the corresponding human menstrual cycle, which averages 28 days.
[16] The distribution of 167,956 spontaneous vaginal deliveries, at 37 to 40 weeks gestation, in Phoenix, Arizona, between 1995 and 2000, showed no relationship with lunar phase.
[2] A review of six additional studies from five different countries similarly showed no evidence of relationship between birth rate and lunar phase.
The belief that there is a large surplus of births on full moon days is incorrect, and it is completely impossible for an observer to detect the small increase of +0.4% in a maternity hospital, even on a long time scale.
[25] The Spanish team acknowledged that the wide variation in the number of admissions throughout the lunar cycle limited the interpretation of the results.
[24] In October 2009, British politician David Tredinnick asserted that during a full Moon "[s]urgeons will not operate because blood clotting is not effective and the police have to put more people on the street.".
[31][32][33] In January 2008, New Zealand's Justice Minister Annette King suggested that a spate of stabbings in the country could have been caused by the lunar cycle.
[34] A reported correlation between Moon phase and the number of homicides in Miami-Dade County was found, through later analysis, not to be supported by the data and to have been the result of inappropriate and misleading statistical procedures.
[35] The authors speculate that the increase might be due to visual distractions created by the moon, especially when it is near the horizon and appears abruptly between trees, around turns, etc.
[39] A meta-analysis of thirty-seven studies that examined relationships between the Moon's four phases and human behavior revealed no significant correlation.
[40] A 2013 study by Christian Cajochen and collaborators at the University of Basel suggested a correlation between the full Moon and human sleep quality.
[42] A 2014 study with larger sample sizes (n1=366, n2=29, n3=870) and better experimental controls found no effect of the lunar phase on sleep quality metrics.
[47] As for how the belief started in the first place, a 1999 study conjectures that the alleged connection of moon to lunacy might be a ‘cultural fossil’ from a time before the advent of outdoor lighting, when the bright light of the full moon might have induced sleep deprivation in people living outside, thereby triggering erratic behaviour in predisposed people with mental conditions such as bipolar disorder.
[6][7][8] Correlation between hormonal changes in the testis and lunar periodicity was found in streamlined spinefoot (a type of fish), which spawns synchronously around the last Moon quarter.
[56] In 2000, a retrospective study in the United Kingdom reported an association between the full moon and significant increases in animal bites to humans.
The study reported that patients presenting to the A&E with injuries stemming from bites from an animal rose significantly at the time of a full moon in the period 1997–1999.
