Postmetamorphic growth, survival, and age at first reproduction of the salamander,hynobius nebulosus tokyoensis Tago in relation to a consideration on the optimal timing of first reproduction

Summary The postmetamorphic growth and survival of the salamanderHynobius nebulosus tokyoentis Tago were surveyed in the study site located in Habu village of Hinodemachi, a suburb of Tokyo City, during 1975–1981. A laboratory experiment on the growth rate of juveniles was conducted in parallel with the field survey. The result indicated that this salamander grew at the rate of 8,mm in s.v.l. per year during the juvenile stage, but its growth rate decreased markedly as low as 1.8 mm for males and 1.1 mm for females, once it had attained sexual maturity. According to the “capture-recapture” procedure the annual survival rate after metamorphosis was found to be quite high; that is, approximately 0.7. By using the growth rate of juveniles and the difference between the sizes at metamorphosis and sexual maturity, the age at first reproduction was estimated to be 4 year for males and 5 year for females. From the data obtained in this study, the intrinsic rates of increase (r) were calculated for various values of age at first reproduction under different survival schedules, and the relationship between the age at first reproduction and fitness as measured byr was examined. The result indicated that an optimal age maximizing fitness always existed under respective survival schedules, and the observed age at first reproduction of this salamandei was found to coincide well with the predicted optimal age.     

Stabilization of the population of a parasite on fruit by the population of a cleptoparasite

Summary When there exist two species such that one is a parasite on fruit and the other exploits the parasitized fruits, they must compete for a limited resource with each other. The relation betweenDacus cucurbitae andAtherigona orientalis is an example of such a situation. We raise a question whether the population of a parasite on fruit can be stabilized by the existence of the cleptoparasite of the parasite on fruit. The changes in their population densities are represented as a differential equation with time delayed parameters, which is deduced from the context of life histories of the two species. An index representing degree of overlapping of generations (g) is defined as an average oviposition period devided by the average preoviposition period, and the value is assumed to be the same in the two species. The stability of the system is classified by three parameters: the reproductive rate of the parasite on fruits (R), the survival probability of it through competition against the cleptoparasite (p), and the generation overlapping index (g). For small values ofg, e.g. less than some 0.5, the stability is determined mainly by a product ofRp: the values larger than 1 result in no equilibrium and infinite increase of both species, the values near 0 lead to large amplitude oscillations, and the intermediate values make stable equilibria or regular small oscillations. Asg takes the larger values, the stability region in the space (p, R) occupies the larger area. The model presented here is well adjusted to the fluctuating pattern of the population ofD. cucurbitae on Okinawa Is., and would also be applied to analysis of both hyperparasitisms and inquilin. This study was supported partly by Science Research Fund (No. 574092) from the Ministry of Education, Japan.     

Delayed maturation in the colonial coralGoniastrea aspera (Scleractinia): whole-colony mortality, colony growth and polyp egg production

The present study examines (1) the cost of reproduction on colony growth, and (2) relationships among sexual maturity, whole-colony mortality rate and colony growth rate inGoniastrea aspera free from external influences by macrobenthos. Survival of colonies in permanent plots was followed for two years. Egg production by polyps in colonies collected just before the first spawning of a year was estimated by dissecting the polyps. Growth of the colonies (increase in number of polyps) was followed over one annual reproductive cycle. The cost of egg production on colony growth was apparent through colony ontogeny: (1) immature colonies had a greater annual growth rate than mature colonies, but produced almost no eggs; (2) in mature colonies, growth rate was negatively correlated with NE/PV (number of eggs per polyp volume mm^-3). Annual whole-colony mortality was high in colonies with fewer than11 polyps in initial colony size, while mortality was extremely low once a colony grew beyond this size. This critical size for low whole-colony mortality was much smaller than the colony size (40 polyps) which would attain maturity one year later. Age at maturity was estimated as six years. While survival to maturity may be a selective force for the evolution of delayed maturation, the present data suggest that high colony fecundity, achieved after a long growth period as an immature colony, and an abrupt decrease of colony growth rate after maturation are the crucial forces.     

Body image,satisfaction with sexual life,self-esteem,and anxiodepressive symptoms: A comparative study between premenopausal,perimenopausal, and postmenopausal women

Menopause is an important life transition in women, and it is associated with significant physical and psychological changes. This study aimed at examining how the menopausal transition influences body image and satisfaction with sexual life. To this aim, body image dissatisfaction, sexual dissatisfaction, and self-esteem were compared in three groups of women with distinct menopausal status (premenopausal n = 142, perimenopausal n = 66, or postmenopausal n = 149), while controlling for depressive and anxiety symptoms and BMI. Using ANOVA between these three groups, we observed that dissatisfaction with body image was significantly higher in the perimenopausal sample compared with its premenopausal counterpart. In the postmenopausal sample, body image improved, as this group displayed body image scores close to the premenopausal level. In addition, sexual dissatisfaction was significantly increased in the perimenopausal and postmenopausal samples, which is compatible with the concept that higher body appreciation positively predicted sexual function. We conclude that body image dissatisfaction reaches a maximum during the perimenopausal phase, before returning to a level nearly identical between the premenopausal and the postmenopausal phases.     

Egalitarian: From Homophile to Helicophile in Post–World War II America

The presidency of gender in the Anglo-American taxonomy of sexualities historically has been haunted by the irruption of “other” parameters of medicalization, censure, and caesura, not in the least absolute and relative measures of age. Where today’s clinical psychologists feel the need to age-specify adult homosexuality in such Hirschfeldian terms as androphilia, however, the felt need is indeed still essentially clinical. That cosmopolitan expressions such as homosexual, LGB, or queer rarely require such specifications relies on a protracted and today, arguably, complete disarticulation of sex/gender and age/maturity as parameters of sexual orientation, accreditation, and mobilization. Notably disconnected discursive frames gave voice to this Anglophone crystallization of “the normal homosexual” (circa 1950–1980): criminological, psychiatric, psychophysiological, and psychodynamic typologies of “sexual deviation” (variably tending to correlate, align, or subsume same-sex and age-disparate intimacies); territorializing apologias of gay, but also of “Greek,” “pederast,” and “man-boy,” socialities; anthropological-historical exotification of “age-stratified homosexualities”; and mostly European, proto-queer critiques of all “bourgeois” sexual classification.     

What Men Who Have Sex With Men in Peru Want in Internet-Based Sexual Health Information

We aimed to gather information among gay men regarding their preferences for online sexual health information; 1,160 Peruvian MSM, 18 years or older, completed an online survey hosted on www.tunexo.org. The mean age was 26.8 years. Around 90% had post–high school education. The self-reported HIV prevalence was 12.3%. The acceptability of sexual health content was greater in the most highly educated group. The highest rated topics and services of interest were those related to improving sexual and mental health. The least educated group was significantly more interested in “getting prevention messages on mobiles” compared to men with the highest level of education (71% vs. 52%; p < 0.001). Men’s sexual health was of more interest to the 30–39-year-old group compared to the 18–24-year-old one (97% vs. 87%; p = 0.005). Future Web-based interventions related to sexual health among targeted groups of MSM in Peru can be tailored to meet their preferences.     

Quantifying Sexual Orientation Among Homeless and Unstably Housed Women in a Longitudinal Study: Identity,Behavior, and Fluctuations Over a Three-Year Period

ABSTRACT

Sexual orientation has been linked to certain health conditions, and yet quantifying sexual orientation in longitudinal studies is challenging. This study examined different methods of accounting for sexual orientation in a cohort study of 300 homeless and unstably housed women followed every 6 months over 3 years. Altogether, 39.7% (n = 119) could be considered sexual minority at one or more time points based on identity and/or behavior; 16.3% (n = 49) reported shifts in sexual identity. Only 24.0% (n = 72) were identified as sexual minority through a single measure of sexual identity, 27.0% (n = 81) were identified with a single measure of identity and behavior, 33.0% (n = 99) were identified through annual measures of identity and behavior, and 22.0%–22.3% (n = 66–67) were identified through latent class analysis including all identity/behavior measures. This study found that sexual fluidity is common in unstably housed women, and many sexual minority women would be missed in longitudinal studies with different methods of accounting for sexual orientation.     

Preliminary studies on the respiratory energy loss of a spider,Lycosa pseudoannulata

Summary To elucidate the basic food requirement of spiders, the important polyphagous predators of rice-plant insect pests, an attempt was made to measure the respiratory energy loss of fasting spiders,Lycosa pseudoannulata. Relationship between fresh (y) and dry (x) weights of spiders inhabiting the bottom layer of the rice-plant community was represented by the following allometric equation:y=0.428x ^0.872. The carbon dioxide production by previously fed and unfed females under the dark at 29°C 100% R. H. was measured by a titration technique. The relationship between fresh body weight and CO₂ production by unfed animals could be represented by the equationM=aW ^b, M being the CO₂ output per individual per day andW the fresh body weight. The constantb, which determines the slope of curve, was 0.808. Respiration of the adult female with 100 mg fresh weight was 1.155±0.250 mg CO₂/100 g fresh weight/day or 48.69 mg CO₂/g dry weight/day. This value corresponds to 35.81 cal/g fresh weight/day or 150.94 cal/g dry weight/day. Supposing the calorific content of spiders to be 5820 cal/g dry weight, rate of the respiratory energy loss to total energy of the body was estimated to be 2.60%. This rate did not strongly contradict with the loss of fresh body weight before and after the measurement. The metabolic rate showed remarkable fluctuation with changing food supply. The CO₂ production of starved individuals decreased to 83.63±16.34% as compared with individuals which were fed before the measurement.     

Young Adult Dating Relationships and the Management of Sexual Risk

Young adult involvement in sexual behavior typically occurs within a relationship context, but we know little about the ways in which specific features of romantic relationships influence sexual decision-making. Prior work on sexual risk taking focuses attention on health issues rather than relationship dynamics. We draw on data from the Toledo Adolescent Relationships Study (n = 475) to examine the association between qualities and dynamics of current/most recent romantic relationships such as communication and emotional processes, conflict, demographic asymmetries, and duration and the management of sexual risk. We conceptualize ‘risk management’ as encompassing multiple domains, including (1) questioning the partner about previous sexual behaviors/risks, (2) using condoms consistently, and (3) maintaining sexual exclusivity within the relationship. We identify distinct patterns of risk management among dating young adults and find that specific qualities and dynamics of these relationships are linked to variations in risk management. Results from this paper suggest the need to consider relational dynamics in efforts to target and influence young adult sexual risk-taking and reduce STIs, including HIV.     

Amnestic Heterosexism and Bystander Responses to Anti-Gay Bullying

Amnestic heterosexism (AH) reflects the belief that, in contemporary society, people who are lesbian, gay, or bisexual (LGB) no longer experience discrimination related to sexual orientation. We investigated potential associations between individuals’ AH beliefs and their responses to anti-gay bullying. Heterosexual undergraduates (N = 238) completed a measure of AH before responding to a scenario in which a man accuses another man of being a “fag.” As expected, those with greater AH beliefs perceived the situation as less severe/dangerous, felt less personally responsible to intervene, and were more blaming toward the target of bullying. In multivariate analyses, AH was indirectly associated with intent to confront the perpetrator via a path of reduced personal responsibility. Our results indicate that beliefs denying the existence of discrimination based on sexual orientation reduce feelings of personal responsibility to address anti-gay bullying. In turn, low personal responsibility inhibits confrontation of those who perpetrate bullying behaviors.     

The biology of the voleClethrionomys rufocanus: A review

The biology of the gray-sided voleClethrionomys rufocanus in Hokkaido, concerning taxonomy, morphology, phylogeny, distribution, and natural history, is reviewed. Applied issues in forest management (damage, control and census) are also mentioned. AlthoughClethrionomys rufocanus of Hokkaido was originally identified as a distinct species,Evotomys (=nowClethrionomys) bedfordiae Thomas, 1905, current literature generally refers to the gray-sided vole of Hokkaido asClethrionomys rufocanus or asC. rufocanus bedfordiae (vernacular name, the Bedford’s red-backed vole). The gray-sided vole is the most common small mammal in Hokkaido. It inhabits open areas as well as forests, and mainly feeds on green plants. The gray-sided vole has a high reproductive potential; litter size: 4–7; gestation period: 18–19 days; maturation age: 30–60 days old. Although spring-born individuals usually attain sexual maturity in their summer/fall of birth, their maturation is sometimes suppressed under high densities. The breeding season is generally from April to October, but with some regional variation.Clethrionomys rufocanus has a rather specialized diet (folivorous), particularly during winter when it feeds on bamboo grass. Many predators specialize on the grey-sided vole in Hokkaido; even the red fox, which is a typical generalist predator, selectively feeds on this vole. Damage by voles’ eating bark used to be sever on forest plantations in Hokkaido. Censuses of small rodents have been carried out for management purpose since 1954.     

That Man Behind the Curtain: Investigating the Sexual Online Dating Behavior of Men Who Have Sex With Men but Hide Their Same-Sex Sexual Attraction in Offline Surroundings

This study investigates how men who have sex with men (MSM) use chat and dating sites based on theories of stigma-related offline behavior and online self-disclosure. We hypothesize that hidden MSM (those who self-label as heterosexual or who hide their same-sex sexual attraction from family, friends, acquaintances, or a female romantic partner) differ from open MSM in how they behave on gay chat and dating sites and in offline gay venues. Drawing on a survey of 12,002 MSM, we show that hidden MSM tend to mask their identity on gay chat and dating sites while avoiding offline gay venues. They also focus more strongly on online sexual activities (e.g., masturbating during online chats) when using gay chat and dating sites. However, they spend the same amount of time on these sites, and they use them to initiate offline sexual encounters as often and as fast as open MSM.     

Interannual fluctuations in recruitment and growth of the sardine,Sardinops melanostictus, in the sea of Japan and adjacent waters

Recruitment and growth of the sardineSardinops melanostictus fluctuated markedly in the Sea of Japan and adjacent waters between 1978 and 1993. Stock size was calculated using Virtual Population Analysis and average body length in each age class was determined by the number of annual rings on the scales. There is an inverse correlation between average water temperature at a depth of 50 m in the coastal area of the mainland of Japan in winter (January to March) and recruitmentR defined as the number of individuals at 1 year old. There is also an inverse correlation between spawning stock sizeE and reproductive success in (R/E). A multiple regression model using spawning stock size and water temperature in winter as independent variables can explain 73% of variance in reproductive success. It suggests that both density-dependent and density-independent factors perform important roles determining reproductive success. There is an inverse correlation between body length and stock size and this suggests that there is a density-dependent effect on the growth of the sardine.     

Population regulation of the euonymus gall midgeMasakimyia pustulaeYukawa andSunose (Diptera: Cecidomyiidae) by hymenopterous parasitoids

Summary Yearly population fluctuations ofM. pustulae were investigated at 19 sites in Kyushu. In sites where a platygastrid is the only parasitoid of the midge, the percentage parasitism was very low in the incipient stage of the outbreak of the midge populations. After the number of midges reached a peak, the midge populations declined as the percentage parasitism increased, and then the outbreak ceased. On the other hand, in several populations no outbreak was found and the percentage parasitism was constantly at a high level. Therefore, the immediate cause for the outbreak seemed to be a decline of the percentage parasitism. Like the midge, the platygastrid has one generation each year, and its females also emerge in spring to deposit their eggs within host eggs. The decline of the percentage parasitism seemed to be mainly affected by the time lag between emergence periods ofM. pustulae and the platygastrid. In the midge populations parasitized by both the platygastrid and a eulophid (Chrysonotomyia sp.), an extinction of the population was observed, resulting from parasitism by the latter,Chrysonotomyia sp. is polyphagous and multivoltine, and is a late parasitoid, as discussed byAskew (1975). When the density of the midges is very low, the platygastrid may leave the host eggs unparasitized, whileChrysonotomyia sp. may not, because the mature galls are conspicuous.     

Sex,Arts and Verbal Abilities: Three Further Indicators of How American Life is not Improving

Despite clear evidence that Americans’ economic standard of living has improved over the last half-century in terms of income, ownership of technology and housing among other indicators, there is scant evidence from non-economic quality-of-life (QOL) indicators of improved life quality to parallel these economic gains. The present article adds to this list in showing little if any progress in three QOL indicators (the first two about time and activity) that have received less or no attention in the social indicators literature, namely (1) frequency of the highly enjoyable activity of sex, (2) participation in various serious arts activities and (3) scores of verbal ability. The data on sexual activity and verbal ability come from the 1974–2008 General Social Surveys (GSS) from the University of Chicago, and for the arts from the 2008 Survey of Public Participation in the Arts (SPPA) conducted by the US Census Bureau for the National Endowment for the Arts since 1982. All three surveys interviewed nationally representative samples, with over 70% response rates and sample sizes of more than 15,000 adults. The GSS data on sexual frequency show no significant increase in estimated frequency of sex since 1989, despite its strong appeal and the availability of new societal conveniences. This held both before and after adjustment for the age, marital status and education in the population; contrary to expectation, working long hours was associated with increased sex both before and after adjustment for these other demographic predictors. The SPPA trend data on arts participation actually showed a decline in participation, especially after adjustment for its major predictor of years of education; again no decreased participation was found among those working long hours. While scores on verbal ability in the GSS have stayed rather steady since 1974, they have decreased after MCA adjustment for the increased college education in more recent years, as documented by Nie et al. (2009). Thus, contrary to expectations, increases in public education have not been accompanied by improvements on these three indicators.     

Creative Work Environments in Sport Organizations: The Influence of Sexual Orientation Diversity and Commitment to Diversity

Drawing from creative capital theory, the purpose of this study was to examine the degree to which sexual orientation diversity and commitment to diversity were predictive of workplaces that fostered creativity. Data were collected from 653 senior level athletic administrators and aggregated to the athletic department level of analysis (n = 199). Moderated regression indicated that sexual orientation diversity did not influence the presence of a creative work environment. There was however, a significant sexual orientation diversity?×?commitment to diversity interaction. When commitment to diversity was high, there was a positive association between sexual orientation diversity and a creative work environment; on the other hand, when commitment to diversity was low, the aforementioned relationship was negative. Results provide support for the notion that all diversity forms can be a source of enrichment and understanding, thereby benefiting the workplace.     

Sexual Orientation Microaggressions and the Experience of Sexual Minorities

This qualitative study sought to confirm and expand on previous research on sexual orientation microaggressions—subtle discrimination in the form of verbal, behavioral, and environmental slights and indignities as defined by Sue (2010 Sue, D. W. 2010. “Microaggressions in everyday life: Race”. In gender, and sexual orientation Hoboken, NJ: Wiley [Google Scholar]). The study had two primary research questions: Does the data from the sample validate Sue's (2010) typology of sexual orientation microaggressions? Beyond Sue's (2010) typology, are other themes/types of sexual orientation microaggressions present in the data? Using a focus group methodology, data was collected from a sample of self-identified non-heterosexual college students (N = 12). Data analysis confirmed five previously identified themes from Sue's (2010) typology (Endorsement of Heteronormative Culture, Sinfulness, Homophobia, Heterosexist Language/Terminology, and Oversexualization) and demonstrated two new themes (Undersexualization and Microaggressions as Humor). The implications of sexual orientation microaggressions, along with limitations and future research directions, are discussed.     

Changing the Gender Balance in Caring: Fatherhood and the Division of Parental Leave in Norway

In this article, we study fathers’ use of parental leave in Norway, using register data from 1993 to 1997. In 1993, a special father’s quota (1 month) was introduced in the parental leave program. The father’s quota is a success in the sense that 85% of fathers entitled to the leave use it, but few take more than their quota (1 month). One policy intention was to make a real change in the gender balance in care. The analyses show that gender balance in breadwinning has a strong effect on fathers’ use of parental leave: controlling for parents’ educational level, labor market attachment and father’s income, we find that the more mothers contribute to the family economy and the more equalized their earnings are, the more parental leave fathers take.     

Recent Immigration and Studies of Ethnic Assimilation

Studies of ethnic assimilation are frequently based upon status comparisons between the foreign born and their "children," the second generation. The assumption that recent immigration has been negligible and that the foreign born represent a closed population is implicit in that procedure. However, analysis of official statistics indicates that immigrants who arrived since World War II now comprise a substantial share of the foreign-born population, while the foreign born who arrived before quota restrictions are rapidly being depleted by mortality. Recent immigrants, as intended by quota legislation, are of much higher socioeconomic status than immigrants who arrived before World War 1. Hence, characteristics of both recent immigrants and earlier arrivals are confounded in data for the foreign-born population. Existing data do not permit rigorous assessment of this confusion or adequate control for it. This paper suggests that tabulations of the foreign born by "year of arrival" would improve the sociological utility of data for ethnic groups.