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Animals that are toxic often advertise their unprofitability to potential predators through bright aposematic colors while cryptic ones blend in with their natural background to avoid predators. In the poison dart frogs, Oophaga pumilio and O. granulifera, some populations in Costa Rica and Panama display cryptic green and aposematic red color morphs. We herein used reflectance spectra from the dorsum of red and green morphs of these frogs to estimate their perception by the visual systems of three potential predators (birds, lizards, and crabs) against three natural backgrounds (leaves, trunks and leaf litter). Statistical analyses revealed no strong differences in color contrast against backgrounds between the two frog species. However, strong effects of frog morph, predator, background, and their interactions were observed. When viewed against diverse backgrounds, red frogs of both Oophaga species are more color conspicuous to birds and Anoline lizards than to crabs. A strong effect of species was observed on luminance contrast. Concerning the latter, green frogs particularly in O. granulifera appear more conspicuous than red frogs, while birds perceive higher brightness contrasts than lizards or crabs. Our results further support the importance of birds and lizards as Oophaga predators and provide a first quantitative comparison of conspicuousness between these two frog species. [ABSTRACT FROM AUTHOR]

Background: Understanding why youth actively transport to school (ATS) has important health, programming, and policy implications. A growing body of research has revealed that there are common factors that influence this behavior. Collectively, these influences can be categorized into 3 domains: the physical environment (PE), sociocultural environment (SCE), and safety environment (SE). Purpose: Although researchers largely agree that these constructs affect ATS, it is not clearly understood how they may interact and to what degree they may influence ATS behavior. Methods: A logistic regression analysis was performed to determine the influence of PE, SCE, and SE on the odds of walking or biking to school. Results: Both PE and SCE were directly associated with active travel, and the SE had an indirect effect. Discussion: A combination of elements from the PE and SCE significantly impacted the odds of using ATS. The impact of SE was significant enough to alter the direct influence of factors within both PE and SCE on the decision to walk or bike. Translation to Health Education Practice: Findings suggest that programming efforts and research should focus on perceptions of safety as a link to overcoming commonly cited barriers.

Animals often mimic the behaviours or signals of conspecifics of the opposite sex while courting. We explored the potential functions of a novel female-like signal type in the courtship displays of male Enchenopa treehoppers. In these plant-feeding insects, males produce plant-borne vibrational advertisement signals, to which females respond with their own duetting signals. Males also produce a signal type that resembles the female duetting responses. We experimentally tested whether this signal modifies the behaviour of receivers. First, we tested whether the female-like signal would increase the likelihood of a female response. However, females were as likely to respond to playbacks with or without them. Second, we tested whether the female-like signal would inhibit competing males, but males were as likely to produce displays after playbacks with or without them. Hence, we found no evidence that this signal has an adaptive function, despite its presence in the courtship display, where sexual selection affects signal features. Given these findings, we also explored whether the behavioural and morphological factors of the males were associated with the production of the female-like signal. Males that produced this signal had higher signalling effort (longer and more frequent signals) than males that did not produce it, despite being in worse body condition. Lastly, most males were consistent over time in producing the female-like signal or not. These findings suggest that condition-dependent or motivational factors explain the presence of the female-like signal. Alternatively, this signal might not bear an adaptive function, and it could be a way for males to warm up or practice signalling, or even be a by-product of how signals are transmitted through the plant. We suggest further work that might explain our puzzling finding that a signal in the reproductive context might not have an adaptive function. [ABSTRACT FROM AUTHOR]

This article emphasizes the role of parental involvement in the college preparation of Latino elementary and secondary school students. Although literature shows that education is highly valued in Latino families, actual college enrollment rates for Latino youth are below average. This has been attributed to barriers including lack of financial resources, problems in communication with schools, and low familiarity with the college planning process. The American Dream Academy is a university outreach program that is designed to help Latino families overcome these barriers. We conducted a qualitative analysis of speeches that were prepared and delivered by parents at graduation ceremonies of the program from 2007 to 2009. Our analysis revealed six themes: facing challenges, envisioning success, understanding the school system, taking ownership, community raising a child, and creating a supportive home environment. The findings enrich existing literature and help understand the complex systems that are at play with parental involvement in Latino families.

The article explores the genetic diversity and taxonomic position of Oophaga vicentei, a poison frog species found in Panama. The study focuses on a unique color morph of O. vicentei characterized by pale yellow dots on a dark brown background. DNA sequencing was used to determine the relationships and genetic diversity of this population. The results show that the unique color morph forms a distinct group within the species. The article emphasizes the need for further research to fully understand the phylogeny of this species complex and suggests potential investigations into color polymorphism and microhabitat preferences. The study was conducted with proper ethical approval and funding. [Extracted from the article]