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Recognizing conspecific individuals from other members of the community is important for many interactive behaviors, especially those involved in mate selection. We investigated whether male courtship behavior is triggered by chemical cues left by females on the substrate using the sedentary litter-dwelling scorpion Tityus pusillus Pocock, 1893, which is a small and common species distributed throughout the northeast Atlantic Forest in Brazil. In experiments using 50 pairs, we tested whether males recognize females by detecting sex-specific chemicals on the substrate. All males changed their behavior, performing pre-courtship acts when exposed to female-specific chemicals on the substrate, but they did not change their behavior when exposed to a clean substrate lacking female-specific chemicals. These results show that the male T. pusillus alters its behavior in the presence of female chemical cues, suggesting that males recognize females by detecting compounds left on the substrate and that the presence of these chemicals trigger the courtship behavior of the male T. pusillus. [ABSTRACT FROM AUTHOR]

The aim of this cross-sectional study was to investigate beliefs, attitudes and reproductive behaviours in relation to consanguinity in a population living in the backlands of north-eastern Brazil. Data were collected by face-to-face interview from 147 high school students aged 13-20 years and from 532 elderly individuals aged 60 years and over from Brejo dos Santos in the state of Paraíba in 2017. The frequency of consanguineous marriage was found to have increased over the generations, being 15.9% in the parents of the elderly participants, 17.1% in the elderly participants themselves and 20.5% in their descendants. Although 258 (50.9%) of the elderly interviewees opposed consanguineous union, 341 (65.3%) would approve of the marriage of their children with relatives. Both the young (n=108 or 78.3%) and elderly (n=398 or 80.4%) interviewees believed that consanguineous marriages were no more durable than non-consanguineous marriages (p=0.578). Additionally, 408 (82.4%) of the elderly individuals and 108 (80.6%) of the students recognized that spouses in consanguineous unions experience conflicts, just like other couples do (p=0.625). In both groups, the majority of the participants did not believe that consanguinity increased the risk of having children with disabilities. The regression of the two continuous variables 'age' and 'positive attitudes score' showed a significant correlation, suggesting that younger individuals are more susceptible to the influence of cultural factors contributing to consanguinity, such as the opinions of their parents and grandparents. The belief that consanguineous unions are more durable showed a significant difference between elderly individuals in consanguineous and non-consanguineous unions (p=0.001); the former were 2.42 more likely to believe that marriages between relatives contributes to marriage durability. [ABSTRACT FROM AUTHOR]

The article presents information on the intergroup boundaries of Brazilian marriages. The authors look at data from 1991-2008, focusing on the impact that the joint distribution of education, race, and religion have on social change, homogamy, and mate selection in Brazil. The article also discusses race relations, educational expansion, and religious diversity in Brazil. The authors argue that changing patterns of intermarriage are affected by behavioral codes, moral judgments and racial preferences.

There is no consensus whether ideal mate preferences are actually expressed in real choices or whether people choose partners according to traditional sex preferences or seek those similar to them. In order to address these questions, 267 Brazilian university students (120 involved and 147 not involved in a romantic relationship) participated in this study, describing themselves and their current or most recent romantic partner. As inclusion criterion, involved subjects must have been in a stable relationship for at least 12 months. Our results suggest that male choice reflects typical preferences based on Parental Investment Theory. On the other hand, the typical female preferences were not observed; instead, their choices indicate a preference for similar partners to themselves. Given that similarities are important to maintaining long-term relationships, females may adapt their preferences in order to ensure male investment in a long-term relationship. [ABSTRACT FROM AUTHOR]

Summary1. Ptilothrix plumata (Hymenoptera) is a neotropical solitary bee that nests in bare, sandy soils. Data on the biology and behaviour of this species are provided. Egg-to-adult development time of a neotropical solitary bee and its parasitoids is quantified for the first time. 2. The bee showed huge variability in egg-to-adult development time. There are two categories of eggs relative to adult emergence. The same season eggs are those from which adults emerge in the same reproductive season in which the eggs were laid. Adults from next season eggs emerge in the next dry reproductive season. This variability in egg-to-adult development time is reached through prepupal diapause. The bee larval parasitoids Leucospis genalis (Hymenoptera) and Anthrax sp. (Diptera) showed similar range in their development times. The data show that diapause is controlled by season. 3. By synchronising adult emergence, this variability in egg-to-adult development time facilitates mate finding, and population recruitment is a consequence of the bees avoiding the unfavourable reproductive season. [ABSTRACT FROM AUTHOR]