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We studied age-related sexual dimorphism of the terminal abdominal ganglion in the cricket, Gryllus bimaculatus using osmium/ethyl-gallate staining and GABA immunohistochemistry. We determinedthat the volume of the terminal abdominal ganglion increases with increasing body size. The growth ratio between longitude and width in the terminal abdominal ganglion is the same in all nymph stages and sexes. However, the longitudinal growth of the male terminal abdominal ganglion ceases in the 8th instar and the adult stage. Therefore, in the adult stage, sexual dimorphism is observed in ganglion morphology. Additionally, sexual dimorphism is also observed in numbers of neuronal somata and GABA-like immunoreactive neurons in the terminal abdominal ganglion. At the beginning of the 8th instar, the number of somata is greater in female crickets than in males. GABA-like immunoreactive neurons, which were classified into eight clusters, increased between the 8th instar and adult in both sexes, but their numbers were sexually dimorphic in the 7th and 8th instars, and in the adult. Females had a greater number of GABA-like immunoreactive neurons than males. These differences occurred mainly in the 8th neuromere cluster, as well as the anterior region of the 9-11th neuromeres. [ABSTRACT FROM AUTHOR]

We show that the learned vocalizations of male and female large-billed crows (Corvus macrorhynchos) are similar and that their functions and physical features show significant differences from those of other oscine species. We investigate whether the song control nuclei of crows show any sexual differences in size, reflecting differences in their singing behavior, and whether these nuclei are different from those of other songbirds in terms of neural connectivity size and relative to the forebrain. Our Nissi staining results reveal that 1) of the four song nuclei examined (HVC; the robust nucleus of the arcopallium ERA]; Area X; and the dorsolateral medial nucleus [DLM]), HVC, RA, and Area X volumes are significantly larger in males than in females, but DLM volume and body and brain weights show no significant gender differences; and 2) the sizes of song nuclei relative to the forebrain are within the range of other oscines. By injecting a neural tract tracer (Dil) into various song nuclei in brain slices, we found that, as in other songbirds, HVC projects to RA and Area X, while Area X projects to the lateral magnocellular nucleus of the anterior nidopallium (IMAN) and DLM, DLM to IMAN, and IMAN to RA. Our results indicate that, although the crow has songs very different from those of other oscine species, its song nuclei and the connections between them are not obviously different. [ABSTRACT FROM AUTHOR]

In teleosts, the distribution of neurons in the preoptic-hypothalamic region and their associated neurohypophysial hormones, such as vasotocin (VT), appears to be different among species. This differential distribution is thought to reflect the social and/or sexual status of individuals within a species. In the present study, we analyzed the number, size and the distribution of vasotocin/isotocin (VT/IT) neurons in the brains of both male and female medaka (Oryzias latipes) using immunohistochemistry. VT/IT neurons were similarly located in an inverted L-shape in the nucleus preopticus in both gender, as has been already reported in salmonids. However, computer-assisted image analysis revealed sexual dimorphism in the number of VT/IT-immunoreactive (ir) neurons, with greater numbers found in males as compared to females. Further, in the female brain, the number of VT/IT-ir neurons decreased significantly after spawning. In pre-spawning compared to postspawning females, the small-sized VT/IT-ir neurons dominated. Sexual differentiation of the medaka is fully dependent upon the steroid status during the early developmental stages and steroids are also known to trigger gender-specific behavior in the adult medaka. Our findings strongly suggest that VT and/or IT neurons may be functionally related to ovulation and/or the reproductive axes through connections to their steroidal status. [ABSTRACT FROM AUTHOR]

The article discusses the relationship between criticism, television and gender in media research. It mentions that media criticism is a domain which struggles in finding ways of making sense of the relationship between text, audiences, and contexts. It also mentions an increasing body of contemporary critical work on television and sexual difference.

The spectral sensitivity of a lycaenid butterfly, Narathura japonica, was investigated by electroretinography using an integrating sphere that could illuminate the compound eye from almost all directions. Samples were collected from three locations. Butterflies from different locations showed a similar pattern; the first, second, and third peaks (or a shoulder) were located at about 380, 460, and 560 nm, respectively. Males clearly showed the highest sensitivity at the first peak point. In contrast, females showed a higher relative sensitivity than males at the second and third peak points in all samples, and showed broad spectral sensitivity. This male-specific UV-sensitivity is discussed in terms of ecological factors. [ABSTRACT FROM AUTHOR]