Proto-Endocrinological Theories of Masculinity/Femininity (1490-1904).

From the mid-seventeenth century, resorption of a testicular "ferment" and resorption of some part of the semen constituted reputable accounts of secondary sexual characteristics. Only in the early twentieth century was the latter, "recrementitious secretion" theory, explicitly considered superseded by one of internal secretion, an advance ushering in the hormone era. A reconstruction of these proto-endocrinological concepts is offered onward from the first, 1490 print edition of Galen's On Semen. Early modern physicians picking up from Galen deliberated widely on the medium and pathway of male and female testicular influences on "the entire body," including the mind, causing "femininity" and "masculinity" in physical, mental-temperamental, and behavioral terms. A switch is discernible from "heat and strength" (Galen) to blood-borne "virility" or testicular vapor (such as proposed in 1564 by Tomás Rodrigues da Veiga), to iatrochemical postulations of a "seminal ferment" (suggested in the late 1650s, perhaps independently, by Thomas Willis at Oxford and Lambert van Velthuysen in Utrecht), finally to a "seminal recrement" or "reabsorbed semen" concept soon after (emergent in the posthumous work of Giovanni Alfonso Borelli, among others). During the late eighteenth century, mounting controversy surrounded both the very idea of that concept and the involved anatomical pathways, informed by multiple experiments.

Revision of the macropterous subgenus Curtonotus from east China, with the description of a new species (Carabidae, Zabrini, Amara).

Species from east China belonging to the subgenus Curtonotus were studied, resulting in the description of a new species, Amara (Curtonotus) beijingensissp. nov. The type locality is Xiaolongmen Forest Park in Beijing. All the known macropterous Curtonotus species from eastern China are reviewed and for each species taxonomical notes, illustrations, and new provincial records are noted. An improved key for their identification is provided as well.

Central Precocious Puberty (CPP) in Two Girls With Autism Spectrum Disorder (ASD).

In recent years, some cases of central precocious puberty (CPP) have been reported in patients with autism spectrum disorder (ASD). Here, we report CPP in two girls with ASD. The first case was a girl, 7 years and 9 months of age. Breast budding was observed at 7 years and 2 months and pubic hair at 7 years and 8 months of age. She was diagnosed with CPP based on guidelines and ASD according to her developmental history. Considering the psychosocial burden caused by the discrepancy between her cognitive and behavioral development and the progression of secondary sex characteristics, gonadotropin-releasing hormone (GnRH) analog therapy was initiated. Case 2 was a girl, 9 years and 8 months of age. She was diagnosed with ASD according to her developmental history. Treatment using oral aripiprazole for hypersensitivity to touch and taste had been initiated, with the onset of menarche at 9 years and 10 months of age. Breast budding had been observed before 7 years and 6 months old. She was diagnosed with CPP based on guidelines. Considering that menarche was not a significant psychosocial burden and the difficulty for her and her family to attend regular follow-ups, GnRH analog therapy was not initiated. Although the pathophysiological pathway linking ASD and CPP remains to be elucidated clinically, attention to CPP in ASD is needed, considering the increase in reported cases. In addition, the indication of GnRH analog therapy should be judged considering the psychosocial burden associated with secondary sexual characteristics.

Infection with Cryptosporidium parvum Affects Secondary Sexual Characteristics of Male Mice by Altering the Pheromone Content in Preputial Gland.

The olfactory acuity of female mice allows them to discriminate the urinary odors of males. Parasitic infection can reduce the odor attractiveness of male mice to females and result in female aversion or avoidance responses in odor selection. However, the chemical signaling changes in the pheromone contents produced by the foreskin gland were not fully revealed after parasitic infection. Cryptosporidium parvum (C. parvum) is a common zoonotic intestinal parasite and has a wide range of hosts, including human, domestic animals, and wild animals. In this study, we immunosuppressed ICR/CD-1 male mice by dexamethasone sodium phosphate treatment. After C. parvum infection, physiological indexes such as body weight and organ weight were significantly decreased. Furthermore, the gene expression level of MUP (major urinary protein) in liver and urine were significantly down-regulated, which could be the reason for the decrease in urine attractiveness to females. GC-MS was performed to analyze the changes in the pheromone produced by the preputial gland before and after parasitic infection, and the results indicated that the levels of different pheromones were significantly reduced after parasitic infection. In summary, this study reveals that C. parvum infection damages the secondary sexual characteristics of male ICR/CD-1 male mice and decreases the pheromone content produced by the foreskin gland.

Exposure to estrone disrupts the endocrine system of western mosquitofish (Gambusia affinis).

Estrone (E1) is one of the predominant natural estrogens detected in aquatic environments, yet little is known about its effects on the endocrine system in fish. In this study, the sex ratio, secondary sexual characteristics, gonadal histology, and transcriptional levels of genes closely related to sex differentiation and hypothalamic-pituitary-gonadal-liver (HPGL) axis were assessed in western mosquitofish (Gambusia affinis) after a full life-cycle exposure to E1 (0, 25.4, 143, 740, and 4300 ng/L) for 119 days. The results showed that exposure to 4300 ng/L of E1 resulted in 100% female and inhibited the growth of females. Exposure to environmentally relevant concentrations of E1 (143 and 740 ng/L) led to obvious feminization of skeletons and anal fins in males. Exposure to 740 and 4300 ng/L of E1 increased the proportion of mature spermatocytes in females, and exposure to 143 and 740 ng/L decreased the proportion of mature spermatocytes in males. Moreover, the transcripts of genes related to sex differentiation and HPGL axis were changed in the E1-exposed adult fish and embryos inside females. This study has provided valuable data on the endocrine disruption effects of E1 at environmentally relevant concentrations in G. affinis.

No butts about it: using urogenital disparity in a deep-water snapper, Etelis carbunculus (Lutjanidae), for field-based sexual identification.

In this study, the authors describe a process that consistently identified sex based on differences in the length and characteristics of the urogenital papilla septum of Etelis carbunculus, a deep-water snapper (Lutjanidae, Etelinae). These characteristics, regardless of fish size, were found to be accurate for 96% of 157 specimens evaluated. The application of this external sex determination technique expedites the collection of sex-specific data and may perform well for other morphologically similar lutjanid snappers. The non-invasive method also minimizes damage to the fish, thereby allowing either its return to the ocean or landing as a valuable whole fish.

Life-History Traits from Embryonic Development to Reproduction in the American Cockroach.

The American cockroach, Periplaneta americana (Insecta: Blattodea: Solumblattodea: Blattidae), is an urban hygiene pest but also a model organism for physiology and neuroscience study. However, the current description of the developmental process of the American cockroach is insufficient. In this study, we provide a life table of the American cockroach in a stable environment, including embryonic development, nymphal instars and adult reproduction. Our results show that there are 14 nymphal instars of the American cockroach in groups with sufficient living materials and space. The secondary sexual characteristics are evident in last-instar nymphs and adults, namely, the complete absence of the anal stylus in females. The entire embryonic development process was divided into 20 stages on the basis of lateral-view observations of the embryos. The formation of the embryo involves the fusion of paired blastoderm regions with higher cellular density, similar to that in other insects of Polyneoptera. With respect to reproduction, the gamogenetic females produced their first ootheca earlier than the parthenogenic females, and the frequency of oviposition was higher for the former throughout adulthood. Interestingly, group living seems to improve the parthenogenesis success rate in the American cockroach.

[Clinical Characterization of Patients with Ovarian Mass Combined with Dysplasia of Secondary Sexual Characteristics].

Objective To investigate the clinical characteristics of preadolescent and adolescent female patients with ovarian mass combined with dysplasia of secondary sexual characteristics. Methods This study retrospectively analyzed 18 cases of ovarian mass combined with dysplasia of secondary sexual characteristics aged 0-19 years admitted to Peking Union Medical College Hospital from January 2012 to November 2019.By analyzing the clinical manifestations,surgical methods,postoperative pathology,therapies and prognosis of the cases,we summarized the diagnosis and treatment ideas. Results Among the 18 cases,7(7/18,38.9%)developed secondary sex signs before puberty,including 5 cases showing precocity(including 2 cases of juvenile granulosa cell tumor,1 case of gonadoblastoma,1 case of ovarian follicular cyst,and 1 case of 46,XY simple gonadal dysplasia combined with dysgerminoma)and 2 cases presenting masculine manifestations(1 case of steroid cell tumor and 1 case of sclerosing stromal tumor).The rest 11(11/18,61.1%)cases showed abnormal development of secondary sexual characteristics during puberty,including 8 cases with masculine manifestations or abnormal menstruation after menarche(7 cases with sex cord stromal cell tumor and 1 case with cystic granulosa cell tumor),2 cases with primary amenorrhea(1 case with androgen insensitivity syndrome combined with testicular sertoli cell tumor and 1 case with endometriosis cyst combined with reproductive tract malformation),and 1 case diagnosed as 46,XX gonadal dysplasia with serous cystadenoma and no secondary sexual development during puberty. Conclusions Sex hormone levels should be actively tested in the case of prepubertal secondary sexual characteristics appearing early,pubertal secondary sexual characteristics being abnormal(underdevelopment),and/or menstrual abnormalities.Imaging examination should be performed to exclude ovarian organic lesions,and chromosome karyotype analysis should be performed if necessary.The diagnosis of ovarian mass in preadolescent and adolescent females with related symptoms should first be alerted to cord stromal cell tumor.It is recommended to rule out the possibility of combined reproductive tract malformation in the adolescent patients with primary amenorrhea.Chromosome examination should be conducted to rule out the possibility of gonadal dysplasia in the adolescent patients with primary amenorrhea and/or no development of secondary sexual characteristics.

Clinical Characterization of Patients with Ovarian Mass Combined with Dysplasia of Secondary Sexual Characteristics / 中国医学科学院学报

Objective To investigate the clinical characteristics of preadolescent and adolescent female patients with ovarian mass combined with dysplasia of secondary sexual characteristics. Methods This study retrospectively analyzed 18 cases of ovarian mass combined with dysplasia of secondary sexual characteristics aged 0-19 years admitted to Peking Union Medical College Hospital from January 2012 to November 2019.By analyzing the clinical manifestations,surgical methods,postoperative pathology,therapies and prognosis of the cases,we summarized the diagnosis and treatment ideas. Results Among the 18 cases,7(7/18,38.9%)developed secondary sex signs before puberty,including 5 cases showing precocity(including 2 cases of juvenile granulosa cell tumor,1 case of gonadoblastoma,1 case of ovarian follicular cyst,and 1 case of 46,XY simple gonadal dysplasia combined with dysgerminoma)and 2 cases presenting masculine manifestations(1 case of steroid cell tumor and 1 case of sclerosing stromal tumor).The rest 11(11/18,61.1%)cases showed abnormal development of secondary sexual characteristics during puberty,including 8 cases with masculine manifestations or abnormal menstruation after menarche(7 cases with sex cord stromal cell tumor and 1 case with cystic granulosa cell tumor),2 cases with primary amenorrhea(1 case with androgen insensitivity syndrome combined with testicular sertoli cell tumor and 1 case with endometriosis cyst combined with reproductive tract malformation),and 1 case diagnosed as 46,XX gonadal dysplasia with serous cystadenoma and no secondary sexual development during puberty. Conclusions Sex hormone levels should be actively tested in the case of prepubertal secondary sexual characteristics appearing early,pubertal secondary sexual characteristics being abnormal(underdevelopment),and/or menstrual abnormalities.Imaging examination should be performed to exclude ovarian organic lesions,and chromosome karyotype analysis should be performed if necessary.The diagnosis of ovarian mass in preadolescent and adolescent females with related symptoms should first be alerted to cord stromal cell tumor.It is recommended to rule out the possibility of combined reproductive tract malformation in the adolescent patients with primary amenorrhea.Chromosome examination should be conducted to rule out the possibility of gonadal dysplasia in the adolescent patients with primary amenorrhea and/or no development of secondary sexual characteristics.

Effects of dominance and female presence on secondary sexual characteristics in male tufted capuchin monkeys (Sapajus apella).

Alpha status may lead to physiological changes that enhance secondary sexual characteristics, which may serve as competitive signals to conspecific males, sexual signals to females, or possibly a combination of both. Here, we report measurements of secondary sexual characteristics in captive dominant and subordinate male tufted capuchin monkeys (Sapajus apella) with varying access to females. An adult male (who had previously been subordinate while housed with other males) was paired with an adult female. This male-female pair was introduced into a room that housed three other male-male pairs with stable hierarchy arrangements. We analyzed weight, body measurements, facial photographs, and hair cortisol before, during, and after introducing a female into the room. While there were no differences in weight or measurements between alphas and subordinates without physical access to the female prior to or during the female's presence, we found that direct access to the female resulted in dramatic changes in facial appearance, body size, and testicular volume in the male who was paired with her. Overall, we found little evidence to suggest that alpha males advertise their status within all-male groups via sexual secondary characteristics. However, direct physical access to females appears to trigger the development of such characteristics in alpha males. It remains of continued interest to identify the endocrine mechanisms responsible for the development, and possible loss, of secondary sexual characteristics.

Effects of 17α-ethinylestradiol on sex ratio, gonadal histology and perianal hyperpigmentation of Cnesterodon decemmaculatus (Pisces, Poeciliidae) during a full-lifecycle exposure.

The effects of 17α-ethinylestradiol (EE2) on sex ratio, gonopodium morphology, and gonadal histology of C. decemmaculatus were assessed by a full-lifecycle exposure experiment. Newborn fish were waterborne exposed to 30, 100, and 300 ng EE2/L for 90 d, using 50 fish per treatment. Additionally, in December of 2016, a field survey was conducted on a C. decemmaculatus population inhabiting the Girado Creek downstream of the Chascomus city wastewater effluent discharge. After 90 d of exposure, EE2 was able to histologically skew the sex ratio toward females and inhibit the full gonopodium development since the lowest tested concentration (LOEC = 30 ng/L). At higher concentrations, EE2 was toxic, inducing mortality in a concentration-dependent fashion (90 d-LC50 = 109.9 ng/L) and altering the gonadal histoarchitecture, causing neither testes nor ovaries discernible histologically (LOEC = 100 ng/L). In addition, a novel response, perianal hyperpigmentation, was discovered been induced by the EE2 exposure in a concentration-dependent fashion (90 d-EC50 = 39.3 ng/L). A higher proportion of females and perianal hyperpigmentation were observed in wild fish collected from the Girado Creek. The major reached conclusions are: i) EE2 induce different effects on the sexual traits of C. decemmaculatus when exposed from early-life or adult stages. ii) The most sensitive effects observed in the laboratory occur in a creek receiving wastewater effluent. iii) The perianal hyperpigmentation comes-up as a promising biomarker of exposure to estrogenic compounds.

Cambios en los caracteres sexuales secundarios del paciente con disforia de género a consecuencia del tratamiento endocrino en Cuba / Changes in the secondary sexual characteristics of the patient with gender dysphoria as a result of endocrine therapy in Cuba

RESUMEN Introducción: La transexualidad es una incongruencia entre el sexo con el que se nace y el sexo al que se siente pertenecer, por tanto, estas personas desean cambios en su apariencia física que se logran mediante el tratamiento hormonal. Objetivo: Describir los cambios en los caracteres sexuales secundarios en pacientes con disforia de género en Cuba como consecuencia del tratamiento endocrino. Métodos: Se realizó un estudio de revisión de las historias clínicas en 76 pacientes atendidas por disforia de género en los últimos 15 años. Se extrajo la información relacionada con datos sociodemográficos y algunos cambios físicos, como resultado del traamiento hormonal. Para el análisis de los datos se obtuvieron distribuciones de frecuencia de las variables cualitativas, media y desviación estándar de las cuantitativas. Resultados: La mayoría de los pacientes corresponde a transexuales de hombre a mujer (THM). Al año, la mayoría de las personas ya tenían un estadio III o IV de desarrollo mamario (45,3 por ciento de estos tenían estadio III y el 32,3 por ciento estadio IV). Al año de iniciada la atención de los 58 pacientes, 41,4 por ciento tenían un patrón de vello triangular típico del sexo femenino con el que se identifican y a los 2 años ascendió al 80,5 por ciento. Al año se evaluaron 50 por ciento de todos los casos y en ese momento solo 5,1 por ciento mantenían un vello facial intenso y más de la mitad (56,8 por ciento), ya no tenían. Al inicio, la media del volumen testicular fue de 17,4 ml, a los 3 meses fue de 15,7 ml, a los 6 meses 14,3 ml y 9,7 ml al año. Conclusiones: Los pacientes con disforia de género en la mayoría de los casos logran cambios en los caracteres sexuales secundarios acordes al sexo con que se identifican(AU)

ABSTRACT Introduction: Transsexualism is an inconsistency between the sex with which someone was born and the sex he or she feels belong to; therefore, these subjects want to do changes in their physical appearance that are achieved through hormonal treatment. Objective: To describe changes in the secondary sexual characteristics in patients with gender dysphoria in Cuba as a result of endocrine therapy. Methods: A study was conducted to review the clinical records in 76 patients treated by gender dysphoria in the past 15 years. It was collected the information related to socio-demographic data and some physical changes as a result of the hormonal therapy. For data analysis were obtained frequency distributions of the qualitative variables, the mean and the standard deviation of the quantitative ones. Results: The majority of patients correspond to male to female transsexuals (THM, by its acronym in Spanish). A year after, the majority of the patients already studied had a stage III or stage IV of breast development (45.3 percent) of these had stage III and 32.3 percent had stage IV). A year after the start of the attention of the 58 patients, 41.4 percent had a pattern of triangular hair typical of the female sex which they feel identified with and after 2 years it increased to 80.5 percent. After a year, there were evaluated 50 percent of all cases and at that time only 5.1 percent maintained intense facial hair, and more than half (56.8 percent) had no facial hair. At the beginning, the mean of testicular volume was 17.4 mL, after 3 months it was 15.7 mL, after 6 months was 14.3 mL and 9.7 mL after a year. Conclusions: Patients with gender dysphoria in most cases achieve changes in the secondary sexual characteristics in accordance with the sex which they feel identified with(AU)

Gradual, temperature-induced change of secondary sexual characteristics in Trichogramma pretiosum infected with parthenogenesis-inducing Wolbachia.

Intersex is an intermediate stage of sexual differentiation in insects. Determining intersex morphology and the cause of its production will aid in the understanding of the mechanism of sexual differentiation in insects. In this paper, Wolbachia-infected Trichogramma pretiosum (T. preW+ ) that shows thelytokous parthenogenesis were used as subjects. In order to determine the causes of the T. preW+ intersex and the influence of parental generation temperature on gradual changes in secondary masculinization in intersex offspring, we examined the occurrence of intersex offspring (F1 and F2 generation) after the parental generations were treated with high temperature (27, 29, 31, and 33 °C) and described the external morphology of the intersexes. The results showed that the T. preW+ parental generation temperature is positively correlated with the probability of intersex offspring. The probability of F1 intersex is significantly higher than that of F2 intersex in different high temperature. The degree of secondary masculinization in T. preW+ intersexes increases as parental generation temperature increases. In addition, our study first identified 11 intersex types in T. preW+ and found that the primary and secondary sexual characteristics showed a regular distribution. We also found that the D type and H type of intersex have the highest frequency of appearance. The external genitalia of most intersexes were female, and only three intersex types have male external genitalia. Conclusions were ultimately obtained: Wolbachia is a direct factor that causes the occurrence of intersexes, while high temperature is an indirect factor that determines the external morphology of intersexes. The effects of high temperature on T. preW+ intersexes is passed through the parental generation to offspring, and this maternal effect weakens as the number of generations increases. In T. preW+ intersex individuals, most exhibit female primary sexual characteristics, and secondary sexual characteristics exhibit signs of masculinization.

Seasonal variations in serum concentrations of testosterone, testicular volume and neck circumference of fallow deer (Dama dama) kept ex situ in a tropical region.

The fallow deer (Dama dama) is a species of Cervidae commonly kept in captivity, either in commercial farms or in zoos. The reproductive seasonality of this species is well known in the northern hemisphere, where photoperiod is a decisive factor in androgenic activity and, consequently, in the development of secondary sexual characteristics among male adults. The maintenance of this species in tropical regions has been successful, but there are no studies that demonstrate the maintenance of reproductive seasonality under these climatic conditions, which was the objective of the present study. To do so, the present investigation involved 27 fallow deer (D. dama) specimens, of which 14 were adults and 13 prepubescent (<8 months) individuals, all assessed during and outside (December-February) the reproductive season (June-August). The serum concentrations of testosterone, testicular volume, and neck circumference were analyzed among all animals during both seasons. The reproductive season was marked by expressive hormonal concentrations, increasing neck circumference and testicular volume, differing significantly between adults and prepubescent individuals outside the season. Positive correlations were observed among all analyzed variables: mean testicular volume and neck circumference (r = 0.92, p < 0.0001), testicular volume and testosterone concentrations (r = 0.79, p < 0.0001) and between neck circumference and testosterone concentrations (r = 0.67, p < 0.0001). Given the results found, the conclusion is that even under tropical climate conditions the reproductive seasonality of the fallow deer is well defined and may be related to photoperiod.

Fifteen new species of Chilicola (Oroediscelis) (Hymenoptera: Colletidae: Xeromelissinae) with illustrated keys to the males and females of the subgenus.

Fifteen new species of Chilicola subgenus Oroediscelis are described and illustrated. The following 11 species are from Argentina recording a remarkable diversity and the first records of the subgenus in the country: Chilicola capillitas Packer and Dumesh, new species, C. abrebotellas, Packer and Dumesh, new species; C. goloboffi Packer and Dumesh, new species; C. fritzi, Packer and Dumesh, new species; C. rozeni Packer and Dumesh, new species; C. roigi Packer and Dumesh, new species; C. carpenteri Packer Dumesh, new species; C. calchaqui Packer and Dumesh, new species; C. jaguense Packer and Dumesh, new species; C. cuyense Dumesh Packer, new species; and C. huarpe Packer and Dumesh, new species. Chilicola pustulata Packer and Dumesh, new species, and Chilicola luna Dumesh, and Packer new species, are described from Peru; C. boharti Packer and Dumesh, new species, and C. ashei Dumesh and Packer, new species, are described from Bolivia, where C. carpenteri also occurs. An unusual feature of the male antennae is described: long setae on F2 and F3 (less commonly F4) that are appressed to, and occasionally longer than, the succeeding flagellomere. Additional records for previously described species are listed and a revised key to males is provided as well as a provisional complete key for all females.

Transcriptomic and physiological changes in western mosquitofish (Gambusia affinis) after exposure to norgestrel.

Norgestrel (NGT) is a synthetic progestin used in human and veterinary medicine. Adult female mosquitofish were exposed to NGT for 42 d at 377 ng L-1. The fin morphology and the liver transcriptome were assessed. NGT exposure increased ray 4:6 length ratio. As compared to the control, NGT treatment affected the expression of 11,772 annotated transcripts in female mosquitofish. Specifically, we found 5780 were repressed while 5992 were significantly induced. Gene ontology (GO) analysis showed that 53 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways and 158 GO terms were significantly over expressed. Genes showing the largest magnitude of expression changes were related to fin development, androgen biosynthesis, and lipid and fatty acid metabolisms, suggesting the involvement of these biological processes in response to NGT exposure in G. affinis. This first comprehensive study on the transcriptomic alterations by NGT in G. affinis not only provides valuable information on the development of molecular markers but also opens new avenues for studies on the molecular mechanisms of effects of NGT in particular and possibly other progestins in G. affinis.

Baseline corticosterone does not reflect iridescent plumage traits in female tree swallows.

The production of high quality secondary sexual traits can be constrained by trade-offs in the allocation of energy and nutrients with other metabolic activities, and is mediated by physiological processes. In birds, the factors influencing male plumage quality have been well studied; however, factors affecting female plumage quality are poorly understood. Furthermore, it remains uncertain which physiological traits mediate the relationship between body condition and ornaments. In this three-year study of after-second-year female tree swallows (Tachycineta bicolor), we investigated (1) the relationship between baseline corticosterone near the end of the brood-rearing period (CORTBR) and feather colour characteristics (hue, saturation, brightness) the following year, and (2) the relationship between baseline corticosterone measured during incubation (CORTI) and brood rearing (CORTBR), and feather colour in the same year. To control for reproductive effort, we included reproductive parameters as covariates in all analyses. In this first study between CORT and the plumage colour characteristics of a species bearing iridescent feathers, we did not find any relationship between CORTBR and the colour of subsequently-produced feathers, nor did we find any relationship between CORT and the colour of feathers displayed during that breeding season. If CORT levels at the end of breeding carry over to influence the immediately subsequent moult period as we expect, our results generally indicate that structural plumage quality may not be as sensitive to circulating CORT levels compared to carotenoid-based colouration. Future studies, particularly those employing experimental manipulations of CORT during moult in species with iridescent traits, are necessary to fully determine the role glucocorticoids play in mediating the quality of secondary sexual characteristics.

Corrigendum: Response: Commentary: Facial Width-to-Height Ratio (fWHR) Is Not Associated With Adolescent Testosterone Levels.

[This corrects the article on p. 160 in vol. 9, PMID: 29520245.].

Differential visual ornamentation between brood parasitic and parental cuckoos.

The evolution of brood parasitism should affect adult phenotypic traits due to sexual selection as well as the parasite-host interactions, although it is rarely focused on. Sexual selection theory predicts extravagant secondary sexual characteristics in brood parasites whereas immature-like modest sexual characteristics in parental species. This is because juvenile-like immature traits can attract mates by exploiting parental care for young (i.e. attraction to young), and because the good parent process, which favours traits that signal parental care ability, would constrain the evolution of costly secondary sexual characteristics due to evolutionary trade-offs between parental investment and sexually selected traits. Using a phylogenetic comparative approach, we studied plumage and bare-part characteristics of adults in relation to brood parasitism in cuckoos (family Cuculidae), in which brood parasitism together with loss of parental care has evolved three times. As predicted, we found that nonparasitic cuckoos had plumage more similar to the juveniles than did brood parasitic cuckoos. Furthermore, nonparasitic cuckoos had a higher probability of having additional bare skin, that is a seemingly less costly, hatchling-like trait, than did brood parasitic cuckoos. This finding further supports the link between parental care and sexual selection, although the influence of a parasite-host interaction cannot be excluded. The analysis of evolutionary pathways suggested interdependent evolution of additional bare skin and brood parasitism. Brood parasitism together with the loss of parental care may prevent the maintenance of a modest phenotype similar to the young, and vice versa in some cases.