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Heterochely denotes the presence of dissimilarly sized chelipeds on opposite sides of the body, a prevalent occurrence in diverse crustaceans. Conversely, heterometry pertains to the quantifiable disparities in size between these chelipeds. Both chelipeds hold pivotal roles in activities such as foraging, mating, and defense. Consequently, individuals of both genders in heterochelic species exhibit this morphological pattern. Previous studies have identified sexual dimorphism in cheliped size, with males displaying larger major chelipeds compared to females, albeit solely relying on propodus length as a size proxy and focusing solely on the major cheliped. In our study, we meticulously examined 190 specimens of the common European hermit crab Pagurus bernhardus from two collections. We sought to elucidate allometric relationships and assess whether heterometry exhibited sex‐based differences when adjusting for body size by using ratios. Our findings revealed that male chelipeds displayed hyperallometric growth relative to females, and all three calculated heterometry indices exhibited significant disparities between the sexes. Consequently, male specimens exhibited larger major and minor chelipeds, even when theoretically matched for body size with females. This phenomenon may be attributed, among other factors, to male–male contests. Should indirect mate selection favor males with larger chelipeds in proportion to their body size, this dynamic could potentiate sexual selection in their favor. [ABSTRACT FROM AUTHOR]

The goal of this study was to explore how distance language learners' pronunciation skills develop with and without targeted pronunciation training during their first semester of university language instruction. To this end, a new computer-assisted method of pronunciation instruction was designed, and its effectiveness, as well as learners' experiences with the method, were assessed. The study was conducted over the course of one semester with 67 distance learners of German. Perception and oral production skills on the word and sentence level were assessed at the beginning and end of the semester for a treatment group that received targeted pronunciation instruction and a control group that did not receive pronunciation instruction, but otherwise followed the same curriculum. The results of the study showed that distance learners' pronunciation skills did not improve significantly over the course of the semester in the absence of targeted pronunciation training. Results further indicated that learners who received targeted pronunciation training improved significantly from pre- to posttest and significantly outperformed learners in the control group on measures of perception and production accuracy at the end of the semester. These findings suggest that distance language instruction can benefit from including targeted pronunciation training.

Even though there is ample evidence that pronunciation plays a crucial role in effective second language (L2) communication, pronunciation training is frequently neglected in L2 classrooms due to time constraints or because instructors do not feel adequately prepared to teach pronunciation. To address this discrepancy, the present study investigates the effectiveness of a novel, homework-based method of pronunciation instruction. Novice German learners' (N = 122) perception and oral production skills on the word and sentence level were assessed at the beginning and the end of the semester. Learners were assigned to 1 of 3 groups: a homework-based pronunciation training group, an in-class training group, and a control group. The results showed that the learners in the homework training group significantly outperformed learners in the control group on some (but not all) measures of phonological perception skills and on comprehensibility measures of productions of individual words. Results further revealed no significant difference between learners who received homework-based or in-class pronunciation training and responses on a debriefing questionnaire showed that learners were equally satisfied with both training modalities. Taken together, these results suggest that homework-based pronunciation training is similarly effective as in-class practice.

Simple Summary: The main mosquito species capable of transmitting arboviruses belong to the genera Aedes spp., Psorophora spp., Anopheles spp., Culex spp., Mansonia spp., Coquillettidia spp., Haemagogus spp., Sabethes spp., Culiseta spp., and Wyeomyia spp. Some neglected mosquito species have the potential to become significant disease vectors due to parameters such as global distribution, rapid adaptation to urban areas, and anthropophilic habits. This review discusses the epidemiological importance and biology of three neglected mosquitoes, Aedes scapularis, Aedes vittatus, and Aedes japonicus japonicus, in the context of vectorial capacity and how urbanization, climate change, and globalization alter disease transmission dynamics and may increase the participation of neglected species in propagating diseases. More than 3550 species of mosquitoes are known worldwide, and only a fraction is involved in the transmission of arboviruses. Mosquitoes in sylvatic and semi-sylvatic habitats may rapidly adapt to urban parks and metropolitan environments, increasing human contact. Many of these mosquitoes have been found naturally infected with arboviruses from the Alphaviridae, Flaviviridae, and Bunyaviridae families, with many being the cause of medically important diseases. However, there is a gap in knowledge about the vector status of newly invasive species and their potential threat to human and domestic animal populations. Due to their rapid distribution, adaptation to urban environments, and anthropophilic habits, some neglected mosquito species may deserve more attention regarding their role as secondary vectors. Taking these factors into account, we focus here on Aedes (Ochlerotatus) scapularis (Rondani), Aedes japonicus japonicus (Theobald), and Aedes (Fredwardsius) vittatus (Bigot) as species that have the potential to become important disease vectors. We further discuss the importance of these neglected mosquitoes and how factors such as urbanization, climate change, and globalization profoundly alter the dynamics of disease transmission and may increase the participation of neglected species in propagating diseases. [ABSTRACT FROM AUTHOR]

This study used questionnaires eliciting quantitative and qualitative data to investigate (1) foreign language learners' beliefs about peer feedback on pronunciation before and after a peer feedback intervention and (2) peer feedback providers', peer feedback receivers', and teacher feedback receivers' experiences of the intervention. Participants included 127 first-year learners of German. They were assigned to a peer feedback provider group, a peer feedback receiver group, a teacher feedback receiver group, or a control group. After a general pronunciation training for the first three groups and a metacognitive instruction session for the first two groups, the peer feedback providers were instructed to give feedback on their peers' pronunciation whereas the peer feedback receivers were asked to incorporate their peers' feedback and the teacher feedback receivers were asked to incorporate feedback from their teachers. Quantitative and qualitative data from a pre- and post-intervention beliefs questionnaire revealed that while all groups held mostly positive beliefs about peer feedback before the intervention, only the peer feedback providers' beliefs changed over time, specifically, their beliefs about peer feedback were significantly more positive after the intervention. Data from an exit questionnaire further indicated that the teacher feedback receivers found their feedback more useful than the peer feedback receivers. Moreover, while the peer feedback providers found correcting peers beneficial for their own language development, many of them felt uncomfortable giving feedback, whereas the peer feedback receivers did not feel uncomfortable receiving it. These findings suggest that peer feedback providers may need additional instruction to help them feel more comfortable correcting other learners. [ABSTRACT FROM AUTHOR]

The present study investigated the impact of pronunciation training on the learning and retention of second language (L2) grammatical structures. By drawing on the phonological saliency of stress placement in German separable- and inseparable-prefix verbs, the study explored whether enhancing explicit instruction through pronunciation training can boost learners' accuracy with the target grammatical form. Learners' command of separable- and inseparable-prefix verbs was tested prior to and after a grammar lesson using a listening task in which participants identified whether target verbs contained a separable or inseparable prefix and a written production task in which participants described pictures using separable- and inseparable-prefix verbs. Results revealed significant and sustained improvement on both the listening and written production task among the grammar + pronunciation group, which suggests that pronunciation training can facilitate the learning and retention of L2 grammatical structures over and above explicit instruction.

This study investigated to what extent teacher and peer feedback promote L2 lexical stress perception skills and how gains are maintained over time. Eighty-two participants from 11 sections of first-year German courses at three universities were assigned to a teacher feedback group, a peer feedback provider group, a peer feedback receiver group, or a control group. After completing a pronunciation training on word stress in German–English cognates, the teacher group received feedback on their pronunciation from a teacher, the provider group gave feedback to peers, and the receiver group received feedback from peers. The control group did not complete the pronunciation training or receive feedback. Results comparing learners' pretest, immediate posttest, and delayed posttest perception accuracy revealed that the teacher group and the provider group made significant gains in terms of their ability to perceive word stress in cognates, whereas the receiver group and the control group showed no improvement. [ABSTRACT FROM AUTHOR]