Lunar biological effects and the magnetosphere

The moon cycle influences reproductive and productive traits in guinea pigs (Cavia porcellus) from a tropical Andean area

There is currently innumerable evidence showing that the lunar cycle affects various reproductive aspects in farm animals. However, there is very little information on the effect of the lunar cycle on productive traits in these species. A retrospective study was conducted (2015-2018) to evaluate the influence of the lunar cycle on some reproductive and productive traits in a guinea pig (Cavia porcellus) production system in the southern Andean region of Ecuador. A total of 7352 productive and reproductive records of guinea pig females housed in 3 m2 cages with a breeding male were analyzed. The following variables were considered: offspring sex ratio, litter size per cage, number of weaned guinea pigs, mortality, individual and litter weaning weight of guinea pigs, and calving frequency. The lunar cycle was split into eight periods of ~3.7-d length each. Data were analyzed by logistic regression and general linear model, and means were compared by the least mean squares method of the SAS. The offspring sex ratio was not correlated to the lunar cycle. The lunar cycle at mating and calving influenced the litter size per cage, number of weaned, and mortality of guinea pigs. The individual and litter-weaning weights were influenced by the lunar cycle at calving. The frequency of calving was greater around the new and full moon than in the remaining periods of the lunar cycle. In conclusion, the lunar cycle influenced several productive and reproductive traits in guinea pigs, such as litter size, mortality, number of pups weaned, and individual and litter weaning weights. This valuable information may have practical applications in management of guinea pig production systems.

Aggression repeatability in stressed fish in response to an environmental concentration of sertraline and lunar cycle as evidenced by brain metabolomics

Sertraline is an environmental pollutant which received magnified scientific attention due to its global presence in waters. Adverse effects on feeding, reproduction and other traits were observed mostly in unstressed aquatic organisms. Chronic stress, however, induces significant physiological changes, and the effects of sertraline in stressed fish may differ from those observed in non-stressed individuals. The current laboratory study addresses this gap by repeatedly monitoring the individual aggression of chronically stressed juvenile chub (Squalius cephalus L.) using the non-reversing mirror test at an environmental sertraline concentration of 0.022 g/L every three to four days for a period of 39 days. Specifically, it was hypothesized that the level and repeatability of aggressiveness would be (i) correlated with the concentration of sertraline/norsertraline in the fish brain; (ii) linked to the individual brain metabolomic profile described by LC-HRMS analyses; (iii) related to the lunar cycle. Sertraline led to an increase in fish aggression and more repeatable/consistent behaviour compared to control fish. While the level of sertraline in the brain did not correlate with aggressiveness, aggressive responses increased with higher norsertraline concentration. The observed aggressive behaviour also varied depending on the individual metabolomic profile of the brain. The behavioural outcome and metabolic change in fish brain may indicate that sertraline has demonstrated neuroprotective effects by reducing cortisol release. It is possible that fish exposed to sertraline could suffer a blunted stress response under the chronic stressors in the wild. Aggressiveness of both treatments evolved in time, revealing a sinusoid-like pattern corresponding to a lunar cycle with a peak of the aggressiveness during the new moon. There is a need for future studies to focus on this relationship to reveal its details and general validity. Our results emphasize that long-term behavioural variability should generally be taken into account in laboratory behavioural studies.

Lunar Cycle, Climate, and Onset of Parturition in Domestic Dromedary Camels: Implications of Species-Specific Metabolic Economy and Social Ecology

Given energy costs for gestating and caring for male offspring are higher than those of female newborns, external environmental conditions might be regarded as likely to affect the timing of delivery processes differentially depending on the sex of the newborn calf to be delivered. The aim of the present paper is to evaluate the association between environmental stressors such as the moon phase and weather-related factors and the onset of labor in female dromedaries. A binary logistic regression model was developed to find the most parsimonious set of variables that are most effective in predicting the probability for a gravid female dromedary to give birth to a male or a female calf, assuming that higher gestational costs and longer labor times are ascribed to the production of a male offspring. Although the differences in the quantitative distribution of spontaneous onset of labor across lunar phases and the mean climate per onset event along the whole study period were deemed nonsignificant (p > 0.05), a non-negligible prediction effect of a new moon, mean wind speed and maximum wind gust was present. At slightly brighter nights and lower mean wind speeds, a calf is more likely to be male. This microevolutionary response to the external environment may have been driven by physiological and behavioral adaptation of metabolic economy and social ecology to give birth to cooperative groups with the best possible reduction of thermoregulatory demands. Model performance indexes then highlighted the heterothermic character of camels to greatly minimize the impact of the external environment. The overall results will also enrich the general knowledge of the interplay between homeostasis and arid and semi-arid environments.

Increased suicide risk among younger women in winter during full moon in northern Europe. An artifact or a novel finding?

Available evidence suggests that there is no effect of moon phases on suicidal behavior. However, a Finnish study recently reported elevated suicide rates during full-moon, but only among premenopausal women and only in winter. This could not be replicated in an Austrian study and stirred a discussion about whether the Finnish finding was false-positive or if there are unaccounted moderator variables differing between Finland and Austria. The goal of the present study was to provide another replication with data from Sweden, which is geographically more comparable to Finland than Austria. We also investigated the discussed moderator variables latitude and nightly artificial brightness. There were 48,537 suicides available for analysis. The fraction of suicides during the full-moon quarter in winter did not differ significantly from the expected 25% among premenopausal women (23.3%) and in the full sample (24.7%). The incidence risk ratios for full moon quarter in Poisson regression models were 0.96 (95% CI: 0.90-1.02) for premenopausal women and 1.01 (95% CI: 0.99-1.04) for the full sample. According to Bayes-factor analysis, the evidence supports the null-hypothesis (no association) over the alternative hypothesis (some association). We found similar results when we split the data by latitude and artificial nightly brightness, respectively. In line with the Austrian study, there was no increase of suicides in Sweden among premenopausal women in winter during full-moon. The results from the Finnish study are likely false positive, perhaps resulting from problematic but common research and publication practices, which we discuss.

The effect of the lunar cycle on migraine: preliminary findings from a retrospective study

AIM

The purpose of this study was to evaluate the relationship between the lunar cycle and attacks observed in patients diagnosed with migraine and under follow-up in our pediatric neurology clinic.

METHODS

Cases diagnosed with migraine and under follow-up at the Balıkesir University Medical Faculty Pediatric Neurology Clinic, Turkey, undergoing attacks between 01.09.2019 and 01.09.2021, and whose attacks were recorded were included in the study. Patients' migraine attacks were investigated retrospectively, and the stage of the lunar cycle at which they occurred, based on the lunar calendar, was determined.

RESULTS

The mean age of the patients in the study was 13.39 ± 2.64 (8-17) years. Female gender was observed in the majority of attacks in all lunar cycles, and was most common in the first quarter. Headache was most common in the frontal region during the first quarter and full moon, and auras were also most frequent in the first quarter. Stress and exercise were the most frequent migraine-triggering factors in the first and third quarters, and in the full moon. Migraine attacks were shortest in duration in the full moon, and longest in the first quarter. The frequency of attacks (per week) was highest in the new moon and third quarter, and lowest in the full moon.

CONCLUSIONS

This study investigated the relationship between migraine attack characteristics in children and the lunar cycle. It represents the first such investigation of the association between the lunar cycle and pediatric migraine attacks.

Sex-specific association of the lunar cycle with sleep

Using one-night sleep recordings from 852 subjects all living in Uppsala, Sweden, the present study represents one of the largest polysomnography investigations into the association of the 29.53-day long lunar cycle with sleep among men and women and across a wide age range (22-81 years). Following the day after the new moon until the day of the full moon (also named the waxing period), the moon's illumination increases, and the timing of the meridian of the moon is gradually shifted from noontime toward midnight. In contrast, from the day after the full moon until the day of the new moon (also named the waning period), the moon's illumination decreases, and the timing of the meridian of the moon is gradually shifted from early night hours toward noontime. Thus, we focused on the contrast between the waxing and waning periods. Sleep duration was shorter on nights during the waxing period as compared to waning period (P < 0.001). In addition, a significant interaction effect of participants' sex with the lunar period on sleep was noted (P < 0.05). Men, but not women, exhibited lower sleep efficiency (P < 0.001 and P = 0.748, respectively) and were longer awake after sleep onset (P = 0.010 and P = 0.890, respectively) on nights during the waxing period. All associations were robust to adjustment for confounders (including regular sleep disturbances). Our findings suggest that the effects of the lunar cycle on human sleep are more pronounced among men. Based on the cross-sectional design of the study, no firm conclusions can be drawn on the causality of the relations.

Synodic lunar phases and suicide: based on 2605 suicides over 23 years, a full moon peak is apparent in premenopausal women from northern Finland

Suicide data for this study were available for the period of March 1988 to June 2011, and involved 2111 male and 494 female victims from the Finnish province of Oulu. Data for lunar phases during that period were categorised into three groups: new moon (<25% visible), full moon (>75% visible) and other times with values in between. Seasonal effects were controlled with definitions for winter (Nov, Dec, Jan), spring (Feb, Mar, Apr), summer (May, June, July), and autumn (Aug, Sep, Oct). Suicide occurrences during different lunar phases were compared with their expected distribution using multinomial tests with all tests being two-tailed. Statistical significance was set at p < 0.05. No correlation between suicides and moon phase in any of the four seasons was apparent for male victims, but in winter for women it was (p = 0.001). Further analysis of the data revealed that the full moon association was statistically significant only for premenopausal women, defined as female victims younger than 45 years of age. To explain this unexpected finding a number of factors were considered, e.g., the darkness of a northern Finnish winter with increases of SAD and depression especially in premenopausal women, the influence of the lunar periodicity on the menstrual cycle, and cosmogeophysical effects on the humoral and autonomous nervous system.

The influence of lunar cycle at the time of conception on sex offspring distribution in dogs

The effect of seasonal variation and lunar cycles on reproductive parameters in dogs is unknown. Lunar cycles have important effects on several biological events. Controversy exists about the influence of lunar cycles on offspring sex ratio. This study examined the sex offspring distribution of 973 puppies (48% females and 52% males) from 150 bitches in Italy between 2015 and 2020. A two-way ANOVA followed by post-hoc t-test (Bonferroni correction) was used to analyze the influence of season and lunar phase on offspring sex ratio at conception. Sex offspring distribution was not affected by season, whereas lunar phase had a significant effect (p< .05). During the new moon, the proportion of male puppies born was significantly lower than during the full moon phase (p < .05). We conclude that season had no effect on sex offspring distribution. The new moon phase at conception appeared to be related to a lower male sex ratio at birth. Further studies assessing additional factors will help provide a better understanding of the lunar cycle differences observed in the sex ratio distribution of dogs.

Longitudinal observations call into question the scientific consensus that humans are unaffected by lunar cycles

Recent longitudinal observations show that human menstrual cycles, sleep-wake cycles and manic-depressive cycles can become synchronized with lunar cycles, but do so in uniquely complex and heterogeneous ways that are unlikely to have been detected by past studies. Past studies' negative results have given rise to a scientific consensus that human biology and behavior are unaffected by lunar cycles. The recent observations show that synchrony can be temporary, and can occur with more than one type of lunar cycle, more than one phase of a lunar cycle and more than one resonant frequency of a lunar cycle. Given the variability of human responses to lunar cycles, aggregate analyses used in almost all previous studies would likely have cancelled out individuals' responses and led to false negative results. In light of these observations, the question of lunar influence should be investigated further, with longitudinal observations and case-by-case analyses of individuals' data.

Lunar Cycle Influences Reproductive Performance of Crossbred Brahman Cows Under Tropical Conditions

Evidence has accumulated over the years indicating that the moon influences some aspects of the reproductive activity in animals and humans. However, little is known about the influence of the lunar cycle on the reproductive performance of cows under tropical conditions, where the environment strongly affects reproduction. This retrospective study was conducted with the aim of assessing the influence of the lunar cycle on some reproductive traits of tropical crossbred cows managed in a pasture-based system. Data from 5869 reproductive records from two commercial farms localized in the Maracaibo Lake Basin of Zulia State, Venezuela, were analyzed. Variables studied were first service conception rate, calving frequency, first postpartum estrous frequency, and pregnancy frequency. In addition to the lunar cycle, the effects of farm, season, and predominant breed were also considered. Data were analyzed using logistic regression and general linear model from SAS. First service conception was affected by lunar phases and predominant breed, but not by farm or season. For frequencies of calving, first postpartum estrus, and pregnancy, there was no main effect of farm, season, and predominant breed, whereas the effect of lunar phases was highly significant. First service conception was significantly greater in waning than in crescent phase of the lunar cycle. Frequencies of calving, first estrus, and pregnancy were highly correlated and showed greater figures around full moon and new moon. In conclusion, lunar cycle influenced first service conception, attaining greater values in the waning phase of the moon cycle. Frequencies of calving, first postpartum estrus, and pregnancy in crossbred cows showed a clear bimodal rhythm, whose greatest values coincided with new moon and full moon.

Women temporarily synchronize their menstrual cycles with the luminance and gravimetric cycles of the Moon

Many species synchronize reproductive behavior with a particular phase of the lunar cycle to increase reproductive success. In humans, a lunar influence on reproductive behavior remains controversial, although the human menstrual cycle has a period close to that of the lunar cycle. Here, we analyzed long-term menstrual recordings of individual women with distinct methods for biological rhythm analysis. We show that women's menstrual cycles with a period longer than 27 days were intermittently synchronous with the Moon's luminance and/or gravimetric cycles. With age and upon exposure to artificial nocturnal light, menstrual cycles shortened and lost this synchrony. We hypothesize that in ancient times, human reproductive behavior was synchronous with the Moon but that our modern lifestyles have changed reproductive physiology and behavior.

Sex differences in the effects of the moon on ischemic stroke incidence: new findings from Beijing, China

Stroke is a major cause of death and disability in China, and no therapies have proven effective to prevent it. Popular belief holds that the lunar cycle affects human physiology, behavior, and health. The aim of our study is to determine whether the lunar cycle impacts the incidence of stroke subtypes [intracerebral hemorrhage (ICH), transient ischemic attack (TIA) and ischemic stroke (IS)]. We retrospectively extracted the discharge registry data of all patients with first-ever acute stroke hospitalized in the affiliated hospital of Beijing University of Traditional Chinese Medicine during 2002-2015. The onset times of stroke were assigned to four primary lunar phases based on NASA definitions. Chi-square tests and multiple logistic regression analyses were used to estimate the association between the lunar cycle and stroke incidence with adjustment for age, sex and season. A total of 5,965 patients with stroke (4,909 admissions for ischemic stroke IS, 754 admissions for ICH, and 302 admissions for TIA) were evaluated in our study. Subgroup analysis indicated that the admission rates of different sexes for IS tended to have opposite variation during the four moon phases. More female patients were admitted during the new moon than in the first and third quarters, while fewer male patients were admitted during the new moon than in the first and third quarters (χ2 = 15.589, P = .001). Multiple logistic regression analyses revealed that men were more likely to be admitted for IS in the first quarter than during the new moon (odds ratio [OR] = 1.252, 95% confidence interval [CI] = 1.076-1.456) (P = .004), and a corresponding trend was also identified for the third quarter (OR = 1.235, 95% CI = 1.062-1.437) (P = .006). No significant gender differences were shown in ICH or TIA. No sex difference is obvious during the full moon. Moon phases seem to affect both genders, but in very different ways. It seems that the new moon is a protective factor for male ischemic stroke patients and a risk factor for female ones. Woman tends to be more vulnerable than ever at the new moon, so deserves more attention and care. The mechanisms underlying this observation are worth studying further.

Tidal variations of background ionizing radiation and circadian timing of the suprachiasmatic nucleus clock

Recently, correlations of different physiological processes in humans with variations in the local lunisolar gravitational tide force have been observed under highly controlled laboratory conditions. Understanding of the physical nature of this phenomenon needs a comprehensive study of its possible molecular mechanisms. One of the possible timing cues is the strong periodic variation of the emanation fields of radon-222 and its progeny produced by tidal deformations of geological environment. In the present work, we argue that this variation could induce temporal modulation of radiation-induced bystander signaling pathways associated with fundamental regulators of gene expression in the suprachiasmatic nucleus clock.

The relationship between the moon cycle and the orientation of glass eels (Anguilla anguilla) at sea

Links between the lunar cycle and the life cycle (migration patterns, locomotor activity, pulses in recruitment) of the European eel (Anguilla anguilla) are well documented. In this study, we hypothesized that the orientation of glass eels at sea is related to the lunar cycle. The European eel hatches in the Sargasso Sea and migrates across the Atlantic Ocean towards Europe. Upon reaching the continental shelf, the larvae metamorphose into glass eels and migrate up the estuaries, where some individuals colonize freshwater habitats. How glass eels navigate pelagic waters is still an open question. We tested the orientation of 203 glass eels in a transparent circular arena that was drifting in situ during the daytime, in the coastal Norwegian North Sea, during different lunar phases. The glass eels swimming at sea oriented towards the azimuth of the moon at new moon, when the moon rose above the horizon and was invisible but not during the other moon phases. These results suggest that glass eels could use the moon position for orientation at sea and that the detection mechanism involved is not visual. We hypothesize a possible detection mechanism based on global-scale lunar disturbances in electrical fields and discuss the implications of lunar-related orientation for the recruitment of glass eels to estuaries. This behaviour could help glass eels to reach the European coasts during their marine migration.

Full Moon and Out-of-Hospital Cardiac Arrest in Japan - Population-Based, Double-Controlled Case Series Analysis

Background: It is commonly believed that a full moon affects human behavior or the occurrence and outcome of various diseases; thus, the occurrence of out-of-hospital cardiac arrest (OHCA) might increase during full moon nights.

Methods and Results: This nationwide, population-based observational study consecutively enrolled OHCA patients in Japan with attempted resuscitation between 2005 and 2016. The primary outcome measure was the occurrence of OHCA. Based on the double-control method, assuming Poisson sampling, we evaluated the average number of OHCA events that occurred on full moon nights compared with that which occurred on control nights, which included events that occurred on the same calendar days 1 week before and after the full moon nights. A total of 29,552 OHCA that occurred on 148 full moon nights and 58,707 OHCA that occurred on 296 control nights were eligible for analysis. The occurrence of OHCA did not differ between full moon and control nights (199.7 vs. 198.3 per night; relative risk [RR], 1.007; 95% CI: 0.993–1.021). On subgroup analysis, compared with control nights, the RR of OHCA occurrence were 1.013 (95% CI: 0.994–1.032, P=0.166) and 0.998 (95% CI: 0.977–1.020, P=0.866) for cardiac and non-cardiac origins, respectively.

Conclusions: In this population, there was no significant difference in OHCA occurrence between full moon and control nights.

Lunar cycle in homicides: a population-based time series study in Finland

OBJECTIVE

To test whether homicides in Finland vary according to moon phases.

DESIGN

A time series study.

SETTING

Finland.

PARTICIPANTS

6808 homicides committed in 1961-2014.

OUTCOME

Daily numbers of homicides.

METHOD

The daily numbers of homicides were related to eight moon phases and the illuminated percentage of the moon disc using negative binomial regression. To identify lunar patterns, piecewise linear terms of lunar days were used, together with changes from one moon phase to another. Homicides were similarly regressed on quintiles of the illuminated percentage of the moon disc. A periodic term of length 29.53 days was included to detect cyclic patterns. The results were adjusted for sex, age, secular trend, distance from the moon, seasons, weekday, major holidays and temperature.

RESULTS

During the full moon, 15% less homicides were committed than during the new moon (RR 0.85; 95% CI 0.77 to 0.94) and 86% less during the lightest quintile of illumination compared with the darkest quintile (RR 0.14; 95% CI 0.04 to 0.50). Adjustments did not change the results. Piecewise linear regressions showed a significant decline in homicides at the full moon and a rise thereafter. The full moon drop in homicides was directionally similar for seasons, weekdays, sex, age and time periods, and it was particularly pronounced in the early part of period studied (1961-1974). Periodic regression showed a regular cyclic pattern of length 29.53 days (p~0.035).

CONCLUSIONS

Contrary to current scientific opinion, an association exists between moon phases and homicides, and contrary to what has been previously assumed, homicides declined during the full moon, especially in earlier decades. However, the causality of the association remains elusive.

Hypothesis: Folklore perpetuated expression of moon-associated bipolar disorders in anecdotally exaggerated werewolf guise

We hypothesize that Moon-associated signals, recently linked to rapid cycling bipolar disorder, may have triggered extremely rare instances of extreme manic and aggressive behaviour that may be compatible with the folklore of the werewolf. Very limited literature on instances of clinical lycanthropy or violent/manic/madness behaviour in association with the Moon may be due to very rare lycanthropic psychosis and not knowing which signal(s) could determine Moon-mood associations. Mechanistically, lunar effects related to bipolar disorder, mood changes, and psychosis could involve either, or a combination, of the following: (i) some as of yet non-measurable signal or undefined geoelectric/geomagnetic receptor or higher sensitivity in some humans, (ii) Moonlight affecting sleep and/or circadian rhythm, (iii) perinatal imprinting of susceptibility, (iv) lunar-periodic growth, and subsequent consumption, of or exposure to psychotropic agents. Importantly, remarkable recent studies (2018) suggest that links between some Moon cycles and bipolar disorder are conceivable. Further observations suggest a role for periodic changes in lunar distances in combination with the Earth and Sun positions. Targeted research could use insight from astrophysicists. If causal links between Moon signals and mood were corroborated, sufferers may benefit from improved disease understanding. Herein, we systematically review the literature and synthesize the evidence for and against the hypothesis. The werewolf myth could become another instance of folklore popularizing biological variation worthy of investigation such as the book characters created by the psychiatrist Hoffmann in 1845 as a Christmas present for his son; namely, 'Struwelpeter' and 'Zappel-Philipp' (shock-headed Peter and fidgety-Philipp): Their conspicuous characteristics have since been linked to genetic uncombable hair syndrome and ADHD, respectively. Overall, rather than dismissing (seemingly) trivial and uncertain concepts as 'just folklore', scientists should grapple with the roots, causes, and significance of traditions and tales, including the werewolf legend.

Changing Efficacy of Wet Cupping Therapy in Migraine with Lunar Phase: A Self-Controlled Interventional Study

BACKGROUND The aim of this study was to evaluate the effect of blood-letting with wet cupping therapy (WCT) in migraine treatment and to determine whether there was any difference according to the phase of the moon when the treatment was applied. MATERIAL AND METHODS This self-controlled study was conducted in Karabuk between 2014 and 2016. Patients who were diagnosed with migraine were enrolled in the study. Migraine disability assessment questionnaire (MIDAS), demographic characteristics, migraine attack frequency and duration, and family history was used to assess the severity of headache. WCT was applied in 3 sessions and the questionnaire was administered before and 3 months after the final WCT session. Wilcoxon signed-rank test was used in pre-and posttreatment measurements, and the Chi-square test was used to check independence in two-way categorical tables. RESULTS A total of 85 patients were included. The reduction in MIDAS scores and number of migraine attacks was significantly greater in the WCT applications made in the first half of the month compared to those in the second half of the month. Although the reduction in visual analog scale (VAS) scores was greater in the second half of the month, it was also significant in the applications made in the first half of the month. CONCLUSIONS WCT was found to be an effective treatment of migraine. The effect on MIDAS, VAS, and the number of attacks was significantly better when the application was made in the second half of the month compared to those made in the first half.

Simultaneous and intercontinental tests show synchronism between the local gravimetric tide and the ultra-weak photon emission in seedlings of different plant species

In order to corroborate the hypothesis that variations in the rate of spontaneous ultra-weak photon emission (UPE) from germinating seedlings are related to local variations of the lunisolar tidal force, a series of simultaneous tests was performed using the time courses of UPE collected from three plant species-corn, wheat and sunflower-and also from wheat samples whose grains were transported between continents, from Brazil to The Netherlands and vice versa. All tests which were run in parallel showed coincident inflections within the UPE time courses not only between seedlings of the same species but also between the different species. In most cases, the UPE inflections were synchronised with the turning points in the local gravimetric tidal variation. Statistical tests using the local Pearson correlation verified these coincidences in the two time series. The results therefore support the hypothesis of a relationship between UPE emissions and, in the oscillations, the local gravimetric tide. This applies to both the emissions from seedlings of different species and to the seedlings raised from transported grain samples of the same species.