Influence of lunar phases on suicide: the end of a myth? A population-based study

The hypothesis of lunar influence on suicide remains widespread, despite the fact that little scientific evidence to substantiate it. We conducted a population-based study to assess the influence of the lunar phases on suicides according to age, sex, and chosen method. The study included all suicides in Middle Franconia between 1998 and 2003. From a population-based sample of 3351 events, the files of 3054 suicides (1949 males and 1105 females) were complete for the study variables. Data were categorized by lunar phase, sex, age, and chosen method—“violent” vs. “non-violent” acts. No significant relationship was detected between the full, absent, and moon's interphases and suicide incidence. Nevertheless, there was a weak association between the absent moon and choice of a non-violent suicide method in men aged less than the median of 40.2 yrs. There was no evidence of a relationship between suicide and lunar phase. Some explanations for this phenomenon are discussed.     

Completed Suicide with Violent and Non-Violent Methods in Rural Shandong,China: A Psychological Autopsy Study

Background

This study aims to describe the specific characteristics of completed suicides by violent methods and non-violent methods in rural Chinese population, and to explore the related factors for corresponding methods.

Methods

Data of this study came from investigation of 199 completed suicide cases and their paired controls of rural areas in three different counties in Shandong, China, by interviewing one informant of each subject using the method of Psychological Autopsy (PA).

Results

There were 78 (39.2%) suicides with violent methods and 121 (60.8%) suicides with non-violent methods. Ingesting pesticides, as a non-violent method, appeared to be the most common suicide method (103, 51.8%). Hanging (73 cases, 36.7%) and drowning (5 cases, 2.5%) were the only violent methods observed. Storage of pesticides at home and higher suicide intent score were significantly associated with choice of violent methods while committing suicide. Risk factors related to suicide death included negative life events and hopelessness.

Conclusions

Suicide with violent methods has different factors from suicide with non-violent methods. Suicide methods should be considered in suicide prevention and intervention strategies.     

Weight Status,Psychological Health,Suicidal Thoughts,and Suicide Attempts in Dutch Adolescents: Results From the 2003 E‐MOVO Project

This study describes the association between weight status and psychological health, suicidal thoughts and suicide attempts in adolescents from a population‐based study of 21,730 adolescents who responded to a classroom‐based internet questionnaire. It demonstrated clear associations between weight status in adolescents and poor psychological health, suicidal thoughts and suicide attempts, especially in obese individuals. Obese boys and girls were more likely to be classified as “psychologically unhealthy” than were normal weight subjects. They also reported more suicidal thoughts and suicide attempts.     

Differential abnormalities in plasma 5-HIAA and platelet serotonin concentrations in violent suicide attempters: relationships with impulsivity and depression

Brain serotonergic systems may participate in the regulation of mood, impulsivity and aggressive behavior. Because some monoaminergic mechanisms seem to be similar in the central nervous system and peripheral tissues, we tested whether serotonergic or dopaminergic biochemical parameters in peripheral venous blood are related or not to violent suicide behavior.We simultaneously studied plasma serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and platelet 5-HT content in patients within 3 days following a violent suicide attempt and in matched healthy controls. We examined their relationship with depression and impulsivity. Twenty seven drug-free suicide attempters and controls were included. Plasma 5-HIAA and platelet 5-HT concentrations were lower in suicide attempters than in controls. Fifteen patients were classified as impulsive (I), including all patients suffering from personality disorder and alcohol abuse, and 12 as non impulsive (NI), mostly melancholics. MADRS scores were similar in both I and NI suicide attempters.When controlling for age, plasma 5-HIAA was lower in I than in NI suicide attempters or controls; these findings are similar to those we observed recently with CSF 5-HIAA in I and NI violent suicide attempters. Contrarily, platelet 5-HT levels were lower in NI than in I patients or controls. Plasma HVA was not associated with suicide behavior. Plasma 5-HIAA concentration was inversely associated with the degree of impulsivity and platelet 5-HT with the intensity of depression. This study indicates that each peripheral serotonergic index is specifically related to a distinct clinical feature and shows differential alteration according to the impulsivity group. In I and NI drug-free violent suicide attempters an inverse figure between plasma 5-HIAA and platelet 5-HT data was observed indicating a non parallelism between these two peripheral variables. Further prospective studies are needed to investigate whether these peripheral serotonergic parameters may be used as helpful early predictors of violent suicide behavior.     

Major radiation of cheilostome bryozoans: Triggered by the evolution of a new larval type?

A macroevolutionary model is developed to account for the “adaptive radiation”; of cheilostome bryozoans that commenced in the Cenomanian after a long phase of low diversity. Living cheilostome species possess one of two types of larvae; planktotrophic (cyphonautes) larvae of relatively long duration, and brooded non‐planktotrophic (coronate) larvae of short duration. Planktotrophic larvae characterize the paraphyletic “malacostegans”; from which “advanced”; cheilostomes with non‐planktotrophic larvae are thought to have evolved monophyletically. Research on other marine invertebrates suggests that gene flow within and between populations is likely to be poorer in species having non‐planktotrophic larvae, and hence the frequency of allopatric and quasi‐sympatric speciation may be greater. Skeletal evidence of larval brooding in the cheilostomes first appears in the late Albian, immediately before their adaptive radiation, and the evolution of non‐planktotrophy with associated increase in speciation rate is proposed to have triggered this radiation.     

Sex ratios at birth in a Micronesian atoll population

Abstract

The recent suggestion that typically masculinized sex ratios at birth in Micronesian populations may be related to a distinct “Micronesian pattern” of life‐course coital behavior is applied to data on the sex ratio of livebirths on Butaritari Atoll in Kiribati. The data show that sex ratios on Butaritari are highly masculinized and do not vary significantly with changes in maternal age. However, there is a discernible relationship between the length of closed intervals preceding male and female births. The lack of age‐related change in sex ratios in the Butaritari sample is inconsistent with ethnographic data regarding levels of marital coital activity in relation to increasing age and marriage duration. The Butaritari sex ratio data is argued to support the suggestion of a “Micronesian pattern,” although it is posed that further tests of this association are required.     

Proteomic Insights into Endometrial Receptivity and Embryo‐Endometrial Epithelium Interaction for Implantation Reveal Critical Determinants of Fertility

In vitro fertilization has overcome infertility issues for many couples. However, achieving implantation of a viable embryo into the maternal endometrium remains a limiting step in optimizing pregnancy success. The molecular mechanisms which characterize the transient state of endometrial receptivity, critical in enabling embryo‐endometrial interactions, and proteins which underpin adhesion at the implantation interface, are limited in humans despite these temporally regulated processes fundamental to life. Hence, failure of implantation remains the “final frontier” in infertility. A human coculture model is utilized utilizing spheroids of a trophectoderm (trophoblast stem) cell line, derived from pre‐implantation human embryos, and primary human endometrial epithelial cells, to functionally identify “fertile” versus “infertile” endometrial epithelium based on adhesion between these cell types. Quantitative proteomics identified proteins associated with human endometrial epithelial receptivity (“epithelial receptome”) and trophectoderm adhesion (“adhesome”). As validation, key “epithelial receptome” proteins (MAGT‐1/CDA/LGMN/KYNU/PC4) localized to the epithelium of receptive phase (mid‐secretory) endometrium obtained from fertile, normally cycling women but is largely absent from non‐receptive (proliferative) phase tissues. Factors involved in embryo‐epithelium interaction in successive temporal stages of endometrial receptivity and implantation are demonstrated and potential targets for improving fertility are provided, enhancing potential to become pregnant either naturally or in a clinical setting.     

Does diurnal temperature range influence seasonal suicide mortality? Assessment of daily data of the Helsinki metropolitan area from 1973 to 2010

Several studies show a peak in suicide rates during springtime and suggest differences in the seasonal variation of suicides. However, the seasonal distribution of the temperature impact on suicide is less clear. This study investigated the relationship between diurnal temperature range (DTR) on suicide mortality. Daily temperature and suicide data for Helsinki were analyzed for the period of 1973–2010 inclusive. Overall, DTR reached its maximum during the spring from mid-April to mid-June, which is also the season with highest suicide mortality in the study region. Specifically, the seasonal timing and maxima for both DTR and suicides vary from year to year. Time series analysis of DTR and suicide records revealed a significant (P?<?0.01) correlation between the springtime DTR maxima and suicide rates for males. No similar association could be found for females. These results provide evidence that a higher springtime DTR could be linked statistically to a higher seasonal suicide rate each spring, whereas the exact timing of the DTR peak did not associate with the seasonal suicide rate. A possible mechanism behind the springtime association between the DTR and suicides originates from brown adipose tissue (BAT) over-activity. Activation of BAT through the winter improves cold tolerance at the cost of heat tolerance. This might trigger anxiety and psychomotor agitation, affecting mood in a negative way. As a hypothesis, the compromised heat tolerance is suggested to increase the risk of death from suicide.     

Suicide among Manitoba's aboriginal people, 1988 to 1994

OBJECTIVE: To compare and contrast the characteristics of suicides among aboriginal and nonaboriginal people in Manitoba. DESIGN: Retrospective review of all suicides, based on a confidential analysis of records held by the Office of the Chief Medical Examiner. SETTING: Manitoba between 1988 and 1994. OUTCOME MEASURES: Standardized suicide rates, age- and sex-specific suicide rates, blood alcohol level at time of death, psychiatric help-seeking behaviour before suicide and residence on a reserve. RESULTS: Age-standardized suicide rates were 31.8 and 13.6 per 100,000 population per year among aboriginal and nonaboriginal people, respectively. The mean age of aboriginal people who committed suicide was 27.0 (standard deviation [SD] 10.8) years, compared with a mean age of 44.6 (SD 18.8) years for nonaboriginal people who committed suicide (p < 0.001). Blood alcohol levels at the time of death were a mean of 28 (SD 23) mmol/L among aboriginal people and 12 (SD 20) mmol/L among nonaboriginal people (p < 0.0001). Before their death, 21.9% of nonaboriginal suicide victims had sought psychiatric care whereas among aboriginal suicide victims 6.6% had sought care (p < 0.0001). Although the suicide rate was higher among aboriginal people living on reserve than among those living off reserve (52.9 v. 31.3 per 100,000 per year), both of these rates were substantially higher than the overall rates among nonaboriginal people. There were no significant differences in mean age, sex, blood alcohol level and previous psychiatric care among aboriginal people who committed suicide living on and off reserve. CONCLUSIONS: There was a high rate of suicide among Manitoba''s aboriginal people between 1988 and 1994; this rate was comparable to earlier estimates of national suicide rates among aboriginal people. The reserve environment does not, by itself, account for the high suicide rate among Manitoba''s aboriginal people. Further study of help-seeking behaviour and the association between alcohol abuse and suicide, particularly among aboriginal peoples, is indicated.     

Impacts of “supermoon” events on the physiology of a wild bird

The position of the Moon in relation to the Earth and the Sun gives rise to several predictable cycles, and natural changes in nighttime light intensity are known to cause alterations to physiological processes and behaviors in many animals. The limited research undertaken to date on the physiological responses of animals to the lunar illumination has exclusively focused on the synodic lunar cycle (full moon to full moon, or moon phase) but the moon's orbit—its distance from the Earth—may also be relevant. Every month, the moon moves from apogee, its most distant point from Earth—and then to perigee, its closest point to Earth. Here, we studied wild barnacle geese (Branta leucopsis) to investigate the influence of multiple interacting lunar cycles on the physiology of diurnally active animals. Our study, which uses biologging technology to continually monitor body temperature and heart rate for an entire annual cycle, asks whether there is evidence for a physiological response to natural cycles in lunar brightness in wild birds, particularly “supermoon” phenomena, where perigee coincides with a full moon. There was a three‐way interaction between lunar phase, lunar distance, and cloud cover as predictors of nighttime mean body temperature, such that body temperature was highest on clear nights when the full moon coincided with perigee moon. Our study is the first to report the physiological responses of wild birds to “supermoon” events; the wild geese responded to the combination of two independent lunar cycles, by significantly increasing their body temperature at night. That wild birds respond to natural fluctuations in nighttime ambient light levels support the documented responses of many species to anthropogenic sources of artificial light, that birds seem unable to override. As most biological systems are arguably organized foremost by light, this suggests that any interactions between lunar cycles and local weather conditions could have significant impacts on the energy budgets of birds.     

Suicides after pregnancy in Finland, 1987-94: register linkage study.

OBJECTIVE: To determine rates of suicide associated with pregnancy by the type of pregnancy. DESIGN: Register linkage study. Information on suicides in women of reproductive age was linked with the Finnish birth, abortion, and hospital discharge registers to find out how many women who committed suicide had had a completed pregnancy during her last year of life. SETTING: Nationwide data from Finland. SUBJECTS: Women who committed suicide in 1987-94. RESULTS: There were 73 suicides associated with pregnancy, representing 5.4% of all suicides in women in this age group. The mean annual suicide rate was 11.3 per 100,000. The suicide rate associated with birth was significantly lower (5.9) and the rates associated with miscarriage (18.1) and induced abortion (34.7) were significantly higher than in the population. The risk associated with birth was higher among teenagers and that associated with abortion was increased in all age groups. Women who had committed a suicide tended to come from lower social classes and were more likely to be unmarried than other women who had had a completed pregnancy. CONCLUSIONS: The increased risk of suicide after an induced abortion indicates either common risk factors for both or harmful effects of induced abortion on mental health.     

Death in the West — A Regional Analysis of the Youthful Suicide Rate

A remarkable increase of youthful suicides over the past few years has caused the death rate for 15- to 24-year-old adolescents and young adults to rise while there has been a reduction in mortality for all other age groups.To analyze the geographic pattern of this youthful suicide epidemic, a national interstate analysis was done for the years 1964 through 1978. Results indicate a broad regional effect with high ratings of youthful suicide concentrated in the western United States, especially among states of the intermountain region.Statistical analysis shows a strong inverse relationship between youthful suicide and population density. Previous research in this area has usually related high population density (overcrowding) to social and behavioral pathology. The present research indicates, however, that low population density (undercrowding) can also have adverse effects. These undercrowding effects may occur because of social isolation, limited social services and loneliness.     

Serum cholesterol concentration and mortality from accidents,suicide, and other violent causes.

OBJECTIVE--To study the association of mortality from accidents, suicides, and other violent deaths with serum cholesterol concentration. DESIGN--Baseline measurements in two randomly chosen independent cohorts were carried out in 1972 and 1977. Mortality was monitored over 10-15 years through the national death registry. SETTING--Eastern Finland. SUBJECTS--The two cohorts comprised men (n = 10,898) and women (n = 11,534) born between 1913 and 1947. There were 193 deaths due to accidents, suicides, and violence among men and 43 among women. MAIN OUTCOME MEASURE--Mortality from accidents, suicides, and other violent deaths was used as the end point. Deaths from these causes were pooled together in the analyses. RESULTS--Serum cholesterol concentration was not associated with mortality from accidents, suicides, and other violent deaths in the univariate analyses or in the proportional hazards regression analyses including smoking, systolic blood pressure, alcohol drinking, and education. In both genders smoking was more prevalent among those who died from accidents, suicides, and other violent causes than from other causes. Frequent use of alcohol increased mortality from these causes. CONCLUSION--The risk of accidents, suicides, and other violent deaths was not related to serum cholesterol concentration, whereas such deaths were more prevalent in smokers and alcohol drinkers.     

Relationship between Vehicle Emissions Laws and Incidence of Suicide by Motor Vehicle Exhaust Gas in Australia, 2001–06: An Ecological Analysis

Background

Globally, suicide accounts for 5.2% of deaths among persons aged 15 to 44 years and its incidence is rising. In Australia, suicide rates peaked in 1997 and have been declining since. A substantial part of that decline stems from a plunge in suicides by one particular method: asphyxiation by motor vehicle exhaust gas (MVEG). Although MVEG remains the second most common method of suicide in Australia, its incidence decreased by nearly 70% in the decade to 2006. The extent to which this phenomenon has been driven by national laws in 1986 and 1999 that lowered permissible levels of carbon monoxide (CO) emissions is unknown. The objective of this ecological study was to test the relationship by investigating whether areas of Australia with fewer noxious vehicles per capita experienced lower rates of MVEG suicide.

Methods and Findings

We merged data on MVEG suicides in Australia (2001–06) with data on the number and age of vehicles in the national fleet, as well as socio-demographic data from the national census. Poisson regression was used to analyse the relationship between the incidence of suicide within two levels of geographical area—postcodes and statistical subdivisions (SSDs)—and the population density of pre-1986 and pre-1999 passenger vehicles in those areas. (There was a mean population of 8,302 persons per postcode in the study dataset and 87,413 persons per SSD.) The annual incidence of MVEG suicides nationwide decreased by 57% (from 2.6 per 100,000 in 2001 to 1.1 in 2006) during the study period; the population density of pre-1986 and pre-1999 vehicles decreased by 55% (from 14.2 per 100 persons in 2001 to 6.4 in 2006) and 26% (from 44.5 per 100 persons in 2001 to 32.9 in 2006), respectively. Area-level regression analysis showed that the suicide rates were significantly and positively correlated with the presence of older vehicles. A percentage point decrease in the population density of pre-1986 vehicles was associated with a 6% decrease (rate ratio [RR] = 1.06; 95% confidence interval [CI] 1.05–1.08) in the incidence of MVEG suicide within postcode areas; a percentage point decrease in the population density of pre-1999 vehicles was associated with a 3% decrease (RR = 1.03; 95% CI 1.02–1.04) in the incidence of MVEG suicide.

Conclusions

Areas of Australia with fewer vehicles predating stringent CO emission laws experience lower rates of MVEG suicide. Although those emission laws were introduced primarily for environmental reasons, countries that lack them may miss the benefits of a serendipitous suicide prevention strategy. Please see later in the article for the Editors'' Summary     

Nestling sex ratio of golden‐winged warblers Vermivora chrysoptera in an introgressed population

Sex ratio biases in avian species remain controversial, although several studies have documented apparent facultative adjustment of offspring sex ratios. While hybridizing pied and collared flycatchers have exhibited sex ratio skews that may be a response to sex‐based costs associated with hybridization, this appears not to be true of a hybridized population of blue‐winged Vermivora pinus and golden‐winged V. chrysoptera warblers. We examined the primary sex ratio of nestlings in a population of hybrid and introgressed golden‐winged warblers. The sex ratio of 298 nestlings from 81 nests in the population was approximately 50:50. We conducted paternity assignments and analyzed groups of nestlings with shared genetic parents (“genetic broods”) and found no difference from the expected binomial distribution, and no statistically significant relationship between parental species phenotype and nestling sex ratio. We saw no evidence of preferential production of male or female nestlings, and female hybrids were found to mate and breed in the population. This suggests that heterogametic (female) hybrids are both viable and fertile, and thus that Haldane's Rule does not apply to this system. While populations of hybridizing golden‐winged warblers should be monitored for evidence of costs of heterospecific pairings, it is unlikely that adjustment of sex ratios would be the form of compensation for sub‐optimal mating conditions. Our results provide support for the emerging hypothesis that hybrids suffer no disadvantage relative to golden‐winged and blue‐winged warblers.     

Stratification based on reproductive state reveals contrasting patterns of age-related variation in demographic parameters in the kittiwake

Heterogeneity in individual quality can be a major obstacle when interpreting age‐specific variation in life‐history traits. Heterogeneity is likely to lead to within‐generation selection, and patterns observed at the population level may result from the combination of hidden patterns specific to subpopulations. Population‐level patterns are not relevant to hypotheses concerning the evolution of age‐specific reproductive strategies if they differ from patterns at the individual level. We addressed the influence of age and a variable used as a surrogate of quality (yearly reproductive state) on survival and breeding probability in the kittiwake. We found evidence of an effect of age and quality on both demographic parameters. Patterns observed in breeders are consistent with the selection hypothesis, which predicts age‐related increases in survival and traits positively correlated with survival. Our results also reveal unexpected age effects specific to subgroups: the influence of age on survival and future breeding probability is not the same in nonbreeders and breeders. These patterns are observed in higher‐quality breeding habitats, where the influence of extrinsic factors on breeding state is the weakest. Moreover, there is slight evidence of an influence of sex on breeding probability (not on survival), but the same overall pattern is observed in both sexes. Our results support the hypothesis that age‐related variation in demographic parameters observed at the population level is partly shaped by heterogeneity among individuals. They also suggest processes specific to subpopulations. Recent theoretical developments lay emphasis on integration of sources of heterogeneity in optimization models to account for apparently “sub‐optimal” empirical patterns. Incorporation of sources of heterogeneity is also the key to investigation of age‐related reproductive strategies in heterogeneous populations. Thwarting “heterogeneity's ruses” has become a major challenge: for detecting and understanding natural processes, and a constructive confrontation between empirical and theoretical studies.     

Regional Changes in Charcoal-Burning Suicide Rates in East/Southeast Asia from 1995 to 2011: A Time Trend Analysis

Background

Suicides by carbon monoxide poisoning resulting from burning barbecue charcoal reached epidemic levels in Hong Kong and Taiwan within 5 y of the first reported cases in the early 2000s. The objectives of this analysis were to investigate (i) time trends and regional patterns of charcoal-burning suicide throughout East/Southeast Asia during the time period 1995–2011 and (ii) whether any rises in use of this method were associated with increases in overall suicide rates. Sex- and age-specific trends over time were also examined to identify the demographic groups showing the greatest increases in charcoal-burning suicide rates across different countries.

Methods and Findings

We used data on suicides by gases other than domestic gas for Hong Kong, Japan, the Republic of Korea, Taiwan, and Singapore in the years 1995/1996–2011. Similar data for Malaysia, the Philippines, and Thailand were also extracted but were incomplete. Graphical and joinpoint regression analyses were used to examine time trends in suicide, and negative binomial regression analysis to study sex- and age-specific patterns. In 1995/1996, charcoal-burning suicides accounted for <1% of all suicides in all study countries, except in Japan (5%), but they increased to account for 13%, 24%, 10%, 7%, and 5% of all suicides in Hong Kong, Taiwan, Japan, the Republic of Korea, and Singapore, respectively, in 2011. Rises were first seen in Hong Kong after 1998 (95% CI 1997–1999), followed by Singapore in 1999 (95% CI 1998–2001), Taiwan in 2000 (95% CI 1999–2001), Japan in 2002 (95% CI 1999–2003), and the Republic of Korea in 2007 (95% CI 2006–2008). No marked increases were seen in Malaysia, the Philippines, or Thailand. There was some evidence that charcoal-burning suicides were associated with an increase in overall suicide rates in Hong Kong, Taiwan, and Japan (for females), but not in Japan (for males), the Republic of Korea, and Singapore. Rates of change in charcoal-burning suicide rate did not differ by sex/age group in Taiwan and Hong Kong but appeared to be greatest in people aged 15–24 y in Japan and people aged 25–64 y in the Republic of Korea. The lack of specific codes for charcoal-burning suicide in the International Classification of Diseases and variations in coding practice in different countries are potential limitations of this study.

Conclusions

Charcoal-burning suicides increased markedly in some East/Southeast Asian countries (Hong Kong, Taiwan, Japan, the Republic of Korea, and Singapore) in the first decade of the 21st century, but such rises were not experienced by all countries in the region. In countries with a rise in charcoal-burning suicide rates, the timing, scale, and sex/age pattern of increases varied by country. Factors underlying these variations require further investigation, but may include differences in culture or in media portrayals of the method. Please see later in the article for the Editors'' Summary     

Differential visibility of treponemal disease in pre‐Columbian stratified societies: Does rank matter?

Treponemal disease is known to be associated with the compromised community health of permanent village settlement. This association explains its high visibility in the village‐based, arguably chiefdom level, agriculturalist societies of late prehistoric (AD 1300–1600) North America. Within chiefdom‐level societies, health differences have often been demonstrated between mortuary‐defined “elite” and “nonelite” individuals. This theoretically should predict status‐based differences in treponemal disease visibility. The prediction is tested in a five‐site osteological sample (N = 650) from the Dallas phase (AD 1300–1550), a simple mortuary‐defined two‐tiered presumptive chiefdom level maize agriculturalist socioeconomic context from lower east Tennessee. The Dallas phase results affirm a general pre‐Colombian North American pattern of no sex differences and display comparable adult to subadult frequencies. The study also reveals that given a sufficient sample size, “elites” do indeed exhibit a significantly lower frequency of tertiary stage treponemal disease. This can be attributed to better baseline health, which has been previously demonstrated in this sample. It may also be affected by the mortuary inclusion of achieved status individuals whose good health may have facilitated sociopolitical advancement. Another pattern that emerged is an apparent young adult age bias in disease visibility. This suggests that tertiary treponemal disease morbidity may either directly or synergistically factor in early adult age at death. Future research will address the veracity of this association. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.     

Buddha's Painter

This study examines the relationship between media constructions of First and indigenous peoples, and the “performative primitives” who are employed in “cultural” villages in the South African province of KwaZulu‐Natal (KZN), with specific reference to Shakaland where the TV series, Shaka Zulu, was filmed in the late 1970s. A Perceian‐derived semiotic method is applied in analysis of the nature of tourist encounters with performers, the relationship between the Western Same and the African Other, and anthropologists’ /observers’ studies as a kind of cultural tourist. Through a discussion of the relationship between science and priestcraft I offer a theory which accounts for new ways of thinking about relations between emotional and active rhetorical discourses. This new form of “scientific discourse” is argued so as to be couched within related discourses of “development”, “conservation”, and “eco‐tourism”.     

Facultative and non‐facultative sex ratio adjustments in a dimorphic bird species

If parental allocation to each offspring sex has the same cost/benefit ratio, Fisher's hypothesis predicts a sex ratio biased towards the cheaper sex. However, in dimorphic birds there is little evidence for this, especially at hatching. We investigated the pre‐fledgling 1) sex ratio, 2) body condition and 3) sex‐differential mortality in a population of the glossy ibis Plegadis falcinellus, in southern Spain between 2001 and 2011. We defined two age groups for the period between hatching and fledging. We also compared pre‐fledgling with the autumn sex ratio. Metabolic rates were estimated by the doubly labeled water (DLW) technique to establish that sons (the bigger sex) were 18% more energy demanding than daughters, and to compute the predicted Fisher's sex ratio (0.465). As population size increased between years, body condition decreased in both sexes, and mortality increased more for daughters than sons prior to fledging. At the same time, the proportion of males among chicks close to fledging increased (average sex ratio: 0.606) while the proportion close to hatching decreased (average sex ratio: 0.434, in line with Fisher's prediction). Furthermore, the proportions of males at fledging and the following autumn were negatively correlated across years. We suggest that, as population density increased and conditions worsened the larger sex had relatively higher survival. These differences in survival produce a shift from a facultative female‐biased sex ratio at hatching into a non‐facultative male‐biased sex ratio of fledglings. Additionally, the excess of males at fledging was counterbalanced by sex‐related dispersal during the autumn. Overall, glossy ibis sex ratio is a product of a combination of facultative and non‐facultative adjustments triggered by environmental conditions, driven by rapid population growth, and mediated by highly interrelated life‐history traits such as body condition, mortality, and dispersal.