Perinatal health among 1 million Chinese-Americans

The literature on “missing girls” suggests a net preference for sons both in China and among Chinese immigrants to the West. Perhaps surprisingly, we find that newborn Chinese-American girls are treated more intensively in US hospitals: they are kept longer following delivery, have more medical procedures performed, and have more hospital charges than predicted (by the non-Chinese gender difference). What might explain more aggressive medical treatment? We posit that hospitals are responding to worse health at birth of Chinese-American girls. We document higher rates of low birth weight, congenital anomalies, maternal hypertension, and lower APGAR scores among Chinese American girls – outcomes recorded prior to intensive neonatal medical care and relative to the non-Chinese gender gap. To the best of our knowledge, we are the first to find that son preference may also compromise “survivor” health at birth. On net, compromised newborn health seems to outweigh the benefit of more aggressive neonatal hospital care for girls. Relative to non-Chinese gender differences, death on the first day of life and in the post-neonatal period is more common among Chinese-American girls, i.e. later than sex selection is typically believed to occur.     

Neural mechanisms of persistent aggression

While aggression is often conceptualized as a highly stereotyped, innate behavior, individuals within a species exhibit a surprising amount of variability in the frequency, intensity, and targets of their aggression. While differences in genetics are a source of some of this variation across individuals (estimates place the heritability of behavior at around 25–30%), a critical driver of variability is previous life experience. A wide variety of social experiences, including sexual, parental, and housing experiences can facilitate “persistent” aggressive states, suggesting that these experiences engage a common set of synaptic and molecular mechanisms that act on dedicated neural circuits for aggression. It has long been known that sex steroid hormones are powerful modulators of behavior, and also, that levels of these hormones are themselves modulated by experience. Several recent studies have started to unravel how experience-dependent hormonal changes during adulthood can create a cascade of molecular, synaptic, and circuit changes that enable behavioral persistence through circuit level remodeling. Here, we propose that sex steroid hormones facilitate persistent aggressive states by changing the relationship between neural activity and an aggression “threshold”.     

The ontogeny of sex differences in the behavior of patas monkeys

Many studies of sex differences in primates have been based on small experimental groups of peers in which only a limited range of social behavior could be expressed. In addition, the first few months of life are often the focus of such studies, with relatively little attention paid to older juveniles. In this study, 11 male and 9 female juvenile patas monkeys, living in a captive social group with all age-sex classes available, were observed between 1 and 4 years of age. A subset of seven patas monkeys was also observed between birth and 1 year of age. Here, we report the development of sex differences in independence, play, grooming, positioning behavior, and aggression over the juvenile period. Juvenile male patas monkeys played more and in longer bouts than females, but wrestling (rough-and-tumble play) was not more common among males. There were few differences in behaviors directed to male and female juveniles by other group members. Distinct differences emerged only in the behaviors of the juveniles themselves, with females being more active participants in social and aggressive interactions than males. In general, sex differences in patas monkeys show a mixture of patterns, some of which are predictive of adult sex differences and some of which appear to be specific to the particular demands of the juvenile period in this species     

"Contemporary Chinese sex symbols in dreams": Correction to Yu (2009).

Reports an error in "Contemporary Chinese sex symbols in dreams" by Calvin Kai-Ching Yu (Dreaming, 2010[Mar], Vol 20[1], 25-41). Three Chinese characters where printed incorrectly in the article. The correct symbols are shown along with the location of each in the original article. On page 26, 3rd paragraph from the top, the second symbol in the third sentence from the bottom of the paragraph is incorrect. On page 28, 1st paragraph, the 1st symbol in line 7 of the paragraph is also incorrect. The last error on page 28, in which the 1st paragraph, 1st symbol in the last line of the paragraph is incorrect. (The following abstract of the original article appeared in record 2010-05656-003.) The present study aimed to determine how often Chinese people dream of sexual metaphors and to examine the association between the dreaming of sexual experiences and contemporary Chinese sex symbols. A list of sex symbols was derived from a thorough review of the sexual analogies that Chinese people most often use in slang language. This list, together with the Marlowe-Crowne Social Desirability Scale and the Eysenck Personality Questionnaire Revised–Short Form, was administrated to a sample of 608 upper-secondary school graduates from Hong Kong. It was found that the participants rarely dreamed about food analogies for sex, such as “eating litchis” and “bananas or banana-like objects.” By contrast, sex symbols involving weapons and aggressive behavior, such as “knives, swords, or daggers” and “shooting,” occurred in dreams with moderate prevalence rates. Moreover, gender, the frequency of dreaming sexual experiences, and social desirability significantly predicted the frequency scores on the scale formed by these aggressive symbols for sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gonadal hormones modulate the display of submissive behavior in socially defeated female Syrian hamsters

There are striking differences in the behavioral response to social defeat between male and female Syrian hamsters. Whereas males exhibit a prolonged behavioral response to defeat (i.e., conditioned defeat), many females remain aggressive or show only a transient submissive response following defeat. The current study tested the hypothesis that sex steroids underlie this differential behavioral responsivity to social defeat. Female hamsters were ovariectomized and implanted with Silastic capsules containing estradiol (E(2)), testosterone (T), progesterone (P), dihydrotestosterone (DHT), or a blank capsule (no hormone replacement). After a 3-week recovery period, each subject was placed inside the home cage of a larger, more aggressive female for four 5-min defeat trials. The following day, each animal was tested for conditioned defeat by testing it in its own home cage in the presence of a smaller, non-aggressive intruder. Submissive, aggressive, social, and nonsocial behaviors were subsequently scored. Hamsters receiving E(2) or T displayed significantly lower levels of submissive behavior than did animals receiving P, DHT, or no hormone replacement. There were no significant differences in aggressive behavior among groups. These data suggest that gonadal hormones can influence submissive behavior in female hamsters. Collectively, these results suggest that the sex differences observed in conditioned defeat may, in part, be explained by sex differences in circulating gonadal hormones.     

Contemporary chinese sex symbols in dreams.

[Correction Notice: An erratum for this article was reported in Vol 20(3) of Dreaming (see record 2010-17362-003). The publishing year of the article in the correction notice was listed incorrectly as 2009. The correct publication year for the original article is 2010. The word were was also misspelled in the body of the correction as where.] [Correction Notice: An erratum for this article was reported in Vol 20(2) of Dreaming (see record 2010-12874-005). Three Chinese characters where printed incorrectly in the article. The correct symbols are shown along with the location of each in the original article. An error is also located on page 26, 3rd paragraph from the top, second symbol in the third sentence from the bottom of the paragraph. On page 28, 1st paragraph, the 1st symbol in line 7 of the paragraph is incorrect. The last error is on page 28, in which the 1st paragraph, 1st symbol in the last line of the paragraph is incorrect.] The present study aimed to determine how often Chinese people dream of sexual metaphors and to examine the association between the dreaming of sexual experiences and contemporary Chinese sex symbols. A list of sex symbols was derived from a thorough review of the sexual analogies that Chinese people most often use in slang language. This list, together with the Marlowe-Crowne Social Desirability Scale and the Eysenck Personality Questionnaire Revised–Short Form, was administrated to a sample of 608 upper-secondary school graduates from Hong Kong. It was found that the participants rarely dreamed about food analogies for sex, such as “eating litchis” and “bananas or banana-like objects.” By contrast, sex symbols involving weapons and aggressive behavior, such as “knives, swords, or daggers” and “shooting,” occurred in dreams with moderate prevalence rates. Moreover, gender, the frequency of dreaming sexual experiences, and social desirability significantly predicted the frequency scores on the scale formed by these aggressive symbols for sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship between feather pecking and ground pecking in laying hens and the effect of group size

The aim of this experiment was to study the relationship between feather pecking and ground pecking in laying hens and the effect of group size on feather pecking behaviour. Hisex White hens were kept in floor pens in group sizes of 15, 30, 60 and 120 birds, each with four replicates. Behavioural observations were performed at four different ages and focused on the number of feather pecks and aggressive pecks, both given and received. The part of the body pecked and the location of the bird was recorded as well as the number of pecks made to the floor, feeder and drinker.The results showed that most feather pecking activity occurred in the largest group size (120 birds) and there was some evidence of an increasing frequency of aggressive pecks with increasing group size. The parts of the body which were targets for feather pecking varied depending on the location of the bird giving the peck and the bird receiving it. When looking at the behaviour of individuals, birds doing a lot of feather pecking also showed more ground pecking.     

The Effect of Dolphin-Assisted Therapy on the Cognitive and Social Development of Children with Down Syndrome

Cognitive and speech development are delayed in children with Down syndrome (DS). We investigated the effect of dolphin-assisted therapy (DAT), a form of animal-assisted intervention, on the development of speech/language and social behavior in children with DS. We hypothesized that DAT would improve the social and cognitive functions with respect to verbalization and thereby promote task performance. A semi-crossover design was used to study 45 children with DS: 18 received a weekly one-hour session of DAT for 6 weeks (group A), 12 children (group B) started with swimming pool sessions (control period of 6 weeks) and thereafter received DAT, and 17 children (group C) were put on a waiting list (control period of 6 weeks) before receiving DAT. The parameters “verbalization,” “impulsiveness,” “proper understanding of rules,” “recognition of persons,” and “establishing contacts” were measured using the Matson Evaluation of Social Skills for Individuals with Severe Retardation (MESSIER) before and after DAT, as well as before and after each of the control periods. Repeated measures ANOVA revealed no significant changes for any of the variables during the control periods (swimming pool, waiting list). Following the period of DAT there was a significant improvement in “verbalization” and “recognition of persons,” while “impulsiveness” decreased. No significant changes were found for the other parameters. “Verbalization” continued to increase during the follow-up period of 6 months, while “recognition of persons” slightly decreased. The results of this study provide support for our hypothesis. Through improvements in verbalization and the recognition of persons, the execution of tasks among children with DS receiving DAT improved. Additional studies are needed to determine if these positive effects of DAT are long-term.     

Correction to Yu (2010).

Reports an error in "Contemporary Chinese sex symbols in dreams: Correction to Yu" by Calvin Kai-Ching Yu (Dreaming, 2010[Mar], Vol 20[1], 25-41). The publishing year of the article in the correction notice was listed incorrectly as 2009. The correct publication year for the original article is 2010. The word were was also misspelled in the body of the correction as where. (The following abstract of the original article appeared in record 2010-05656-003.) [Correction Notice: An erratum for this article was reported in Vol 20(2) of Dreaming (see record 2010-12874-005). Three Chinese characters where printed incorrectly in the article. The correct symbols are shown along with the location of each in the original article. An error is also located on page 26, 3rd paragraph from the top, second symbol in the third sentence from the bottom of the paragraph. On page 28, 1st paragraph, the 1st symbol in line 7 of the paragraph is incorrect. The last error is on page 28, in which the 1st paragraph, 1st symbol in the last line of the paragraph is incorrect.] The present study aimed to determine how often Chinese people dream of sexual metaphors and to examine the association between the dreaming of sexual experiences and contemporary Chinese sex symbols. A list of sex symbols was derived from a thorough review of the sexual analogies that Chinese people most often use in slang language. This list, together with the Marlowe-Crowne Social Desirability Scale and the Eysenck Personality Questionnaire Revised–Short Form, was administrated to a sample of 608 upper-secondary school graduates from Hong Kong. It was found that the participants rarely dreamed about food analogies for sex, such as “eating litchis” and “bananas or banana-like objects.” By contrast, sex symbols involving weapons and aggressive behavior, such as “knives, swords, or daggers” and “shooting,” occurred in dreams with moderate prevalence rates. Moreover, gender, the frequency of dreaming sexual experiences, and social desirability significantly predicted the frequency scores on the scale formed by these aggressive symbols for sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The “Normalization” of Intersex Bodies and “Othering” of Intersex Identities in Australia

Once described as hermaphrodites and later as intersex people, individuals born with intersex variations are routinely subject to so-called “normalizing” medical interventions, often in childhood. Opposition to such practices has been met by attempts to discredit critics and reasserted clinical authority over the bodies of women and men with “disorders of sex development.” However, claims of clinical consensus have been selectively constructed and applied and lack evidence. Limited transparency and lack of access to justice have helped to perpetuate forced interventions. At the same time, associated with the diffusion of distinct concepts of sex and gender, intersex has been constructed as a third legal sex classification, accompanied by pious hopes and unwarranted expectations of consequences. The existence of intersex has also been instrumentalized for the benefit of other, intersecting, populations. The creation of gender categories associated with intersex bodies has created profound risks: a paradoxically narrowed and normative gender binary, maintenance of medical authority over the bodies of “disordered” females and males, and claims that transgressions of social roles ascribed to a third gender are deceptive. Claims that medicalization saves intersex people from “othering,” or that legal othering saves intersex people from medicalization, are contradictory and empty rhetoric. In practice, intersex bodies remain “normalized” or eliminated by medicine, while society and the law “others” intersex identities. That is, medicine constructs intersex bodies as either female or male, while law and society construct intersex identities as neither female nor male. Australian attempts at reforms to recognize the rights of intersex people have either failed to adequately comprehend the population affected or lacked implementation. An emerging human rights consensus demands an end to social prejudice, stigma, and forced medical interventions, focusing on the right to bodily integrity and principles of self-determination.     

Relationships between hormones and aggressive behavior in green anole lizards: an analysis using structural equation modeling

We investigated the relationship between aggressive behavior and circulating androgens in the context of agonistic social interaction and examined the effect of this interaction on the androgen-aggression relationship in response to a subsequent social challenge in male Anolis carolinensis lizards. Individuals comprising an aggressive encounter group were exposed to an aggressive conspecific male for 10 min per day during a 5-day encounter period, while controls were exposed to a neutral stimulus for the same period. On the sixth day, their responses to an intruder test were observed. At intervals, individuals were sacrificed to monitor plasma androgen levels. Structural equation modeling (SEM) was used to test three a priori interaction models of the relationship between social stimulus, aggressive behavior, and androgen. Model 1 posits that exposure to a social stimulus influences androgen and aggressive behavior independently. In Model 2, a social stimulus triggers aggressive behavior, which in turn increases circulating levels of androgen. In Model 3, exposure to a social stimulus influences circulating androgen levels, which in turn triggers aggressive behavior. During the 5 days of the encounter period, circulating testosterone (T) levels of the aggressive encounter group followed the same pattern as their aggressive behavioral responses, while the control group did not show significant changes in their aggressive behavior or T level. Our SEM results supported Model 2. A means analysis showed that during the intruder test, animals with 5 days of aggressive encounters showed more aggressive responses than did control animals, while their circulating androgen levels did not differ. This further supports Model 2, suggesting that an animal's own aggressive behavior may trigger increases in levels of plasma androgen.     

Dominant-subordinate relationships in hamsters: sex differences in reactions to familiar opponents

In the majority of mammalian species, males are dominant over and more aggressive than females. In contrast, some reports suggest that female golden hamsters are more aggressive than males but systematic comparisons using the same methods for both sexes are rare. We observed same-sexed pairs of hamsters over repeated trials to assess whether sex differences existed in the level of agonistic behavior and in the development and maintenance of dominant-subordinate relationships with familiar partners. There were no sex differences in measures of agonistic behavior or fear responses (fleeing) during the initial series of three trials on the first day of testing. Following a four-day interval, males that had lost in session 1 showed fearful responses to a familiar dominant male and were not likely to engage in a fight with him. In contrast, females that lost the initial fights were not fearful and fought vigorously with the familiar winner in subsequent encounters. Although the amount of agonistic behavior engaged in by females did decrease over the course of the three sessions, females that lost did not demonstrate an increase in fear, as measured by the latency to flee. Males that lost fights did show increased fear during later trials and sessions. These results suggest that female hamsters are less affected by losing fights than males are and thus that females are less likely than males to develop highly polarized dominant-subordinate relationships. Further work is needed to understand the mechanisms underlying these sex differences.     

Positional behavior of free-ranging Japanese macaques (<Emphasis Type="Italic">Macaca fuscata</Emphasis>)

Positional behavior was quantitatively studied in identified free-ranging Japanese macaques (Macaca fuscata). Five male and 11 female adults were observed in a forested mountain habitat. Data were analyzed for proportion of bout distance, number and time of each locomotion and postural type. Japanese macaques are semiterrestrial, and mainly walk and run quadrupedally. This supports the notion that Macaca are generally quadrupeds. Sex differences in positional behavior were found in the preference of substrate and types of positional behavior. Males and females tend to be terrestrial and arboreal, respectively. Males leap more frequently and longer in distance than do females when they are feeding in trees. These sex differences are considered to be related to differences in morphology, food choice, social activity, and the nursing of infants. Frequencies of leaping and the distance covered by leaping in Japanese macaques are more than those of long-tailed macaques which are arboreal quadrupeds. However, Japanese macaques leap shorter distances at a time than do long-tailed macaques, which indicates that body size may be related to leaping distance more than the frequency of leaping and the distance covered by leaping. Japanese macaques are not as specialized for terrestrial locomotion as pig-tailed macaques. They use both terrestrial and arboreal supports, and are considered to be semi-terrestrial quadrupeds, somewhere between the arboreal long-tailed macaque and the terrestrial pig-tailed macaque. Electronic Publication     

Toward a comparative socioecology of the genus Macaca: Different dominance styles in rhesus and stumptail monkeys

Captive studies can make a unique contribution to primate socioecology by documenting species-typical social dispositions under controlled conditions. Recent theories seek to connect the dominance relationships, group cohesiveness, and feeding ecology of primates. The present study explores the first two aspects by comparing the social organization of rhesus (Macaca mulatta) and stumptail monkeys (M. arctoides). Data were collected over a period of eight years, with five different methods, on three well-established captive groups in identical environments. The groups were found to share one characteristic: a clear-cut, linear formal dominance hierarchy as expressed in teeth-baring displays. The two main study groups (one of each species) differed significantly, however, with respect to nine of eleven behavioral measures. In addition to a previously reported higher frequency of reconciliation in the stumptail group, this group showed (1) more frequent but less severe aggressive behavior, (2) greater symmetry of contests, (3) greater social tolerance, (4) more nonagonistic approaches, and (5) more allogrooming. The differences can be summarized as a contrast in dominance “style,” with the stumptails having a more relaxed style and placing greater emphasis on social cohesion than the rhesus monkeys. An egalitarian attitude was also reflected in approach behavior: contacts in the rhesus group were mostly initiated by dominants, whereas contacts in the stumptail group were initiated independent of rank. Comparisons with a second rhesus group, and with published reports, suggest that while some of the observed differences are probably representative of the two species, considerable intraspecific variation does exist, and a more comprehensive program of comparative studies is needed.     

Contextual modulation of androgen effects on agonistic interactions

Seasonal changes in steroid hormones are known to have a major impact on social behavior, but often are quite sensitive to environmental context. In the bi-directionally sex changing fish, Lythrypnus dalli, stable haremic groups exhibit baseline levels of interaction. Status instability follows immediately after male removal, causing transiently elevated agonistic interactions and increase in brain and systemic levels of a potent fish androgen, 11-ketotestosterone (KT). Coupling KT implants with a socially inhibitory environment for protogynous sex change induces rapid transition to male morphology, but no significant change in social behavior and status, which could result from systemically administered steroids not effectively penetrating into brain or other tissues. Here, we first determined the degree to which exogenously administered steroids affect the steroid load within tissues. Second, we examined whether coupling a social environment permissive to sex change would influence KT effects on agonistic behavior. We implanted cholesterol (Chol, control) or KT in the dominant individual (alpha) undergoing sex change (on d0) and determined the effects on behavior and the degree to which administered steroids altered the steroid load within tissues. During the period of social instability, there were rapid (within 2 h), but transient effects of KT on agonistic behavior in alphas, and secondary effects on betas. On d3 and d5, all KT, but no Chol, treated females had male typical genital papillae. Despite elevated brain and systemic KT 5 days after implant, overall rates of aggressive behavior remained unaffected. These data highlight the importance of social context in mediating complex hormone–behavior relationships.     

Early life predictors of the development of aggressive behaviour in the domestic pig

Individuals show stable differences in their aggressive responses towards unfamiliar conspecifics. We investigated the extent to which variables present during early life could be identified that were correlated with these later individual differences in aggressive behaviour. The behaviour and growth of 125 domestic pigs, Sus scrofa, from 16 litters, were studied from birth until 18 days after weaning, when they were tested on two occasions in resident-intruder tests to measure their aggressiveness. Aggressiveness was affected by litter, although not by sex. A number of early life correlates of later resident-intruder aggressiveness were found at the litter level. Pigs became more aggressive if they had been born into larger litters. Pigs in these aggressive litters were more active in the 8-h period immediately after birth, perhaps taking longer to achieve satiety at the udder. They were also in poorer condition 2 days after birth. Aggressive pigs also engaged in more pushing with littermates over the whole preweaning period. The best correlates of aggressiveness appear to be a number of correlated variables relating to low nutrition, either prenatally or in the early postnatal period. The results are consistent with the concept that early environmental conditions can programme behavioural responses for later life.     

Sex,gender, and difference

Empirical research has demonstrated that women’s aggressive behavior is widespread and displays regularities across societies. Until recently, however, discussions about the aggressive behavior of women and gender differences in aggressive behavior have been based largely on data from nonhuman primates, children, or laboratory experiments. Using a unique corpus of naturalistic data on aggressive human interactions both between and among men and women, I explore the complexity of our questions about sex differences in aggression and further illuminate the ways in which men and women may use aggression in human interactions. In this paper I compare the aggressive behavior of men and women in an Australian Aboriginal community. In doing so I argue for the continuing use of a “sex differences” framework for organizing our understanding of gender relations and gender hierarchy. I believe, however, that this form of analysis benefits from, if not requires, a sensitivity to the most taken-for-granted aspects of our gender ideology and a commitment to attend to evidence that challenges our convictions about men and women.     

Impact of Environmental Disturbance on the Stability and Benefits of Individual Status within Dominance Hierarchies

Changes in environmental conditions affect social interactions and thus may modify an individual's competitive ability within a social group. We subjected three‐spined sticklebacks, Gasterosteus aculeatus, housed in groups of four individuals, to environmental perturbations to assess the impact on dominance hierarchy stability. Hierarchy stability decreased during increased turbulence or lowered water levels (‘simulated drought’) whereas control hierarchies became more stable in a constant environment. The dominant individual either became more aggressive and remained dominant during the environmental manipulation or was usurped by a lower rank member. Only simulated drought affected rates of aggression where levels of aggression were higher after the water level was dropped which may be the result of an increased encounter rate in these conditions. When there were large size differences between the group members, the dominant individual performed the greatest amount of aggression and ate the largest proportion of food and there was little aggressive behaviour from the lower ranks. In groups of similar‐sized individuals, aggression was much higher. The benefit of being dominant was to gain weight over the experimental period whereas ranks 2 and 3 lost weight. The lowest rank, 4, actually gained weight over the experimental period. This study suggests that it would benefit an individual to be dominant, highly aggressive and gain weight or be submissive, avoid aggressive interactions and, by sneakily obtaining access to food, also gain weight. Altering environmental conditions has a profound effect on social behaviour in this study.