14 research outputs found

    Thermal limits and preferences of large branchiopods (Branchiopoda: Anostraca and Spinicaudata) from temporary wetland arid zone systems

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    Highlights: ‱ Thermal biology of rock-pool and pan specialist branchiopods were contrasted. ‱ Wetland type was not a good predictor of branchiopod thermal preference/limits. ‱ Spinicaudatans preferring higher temperatures than anostracans. ‱ Spinicaudatans were more tolerant of high temperatures than anostracans. ‱ Anostracans may be more susceptible to projected climatic warming. Abstract: Large branchiopods are specialist crustaceans adapted for life in temporary, thermally dynamic wetland ecosystems. Certain large branchiopod species are, however, restricted to specific temporary wetland types, exemplified by their physico-chemical and hydroperiod characteristics. Here, we contrasted the thermal preference and critical thermal maxima (CTmax) and minima (CTmin) of southern African anostracans and spinicaudatans found exclusively in either temporary rock-pool or pan wetland types. We hypothesized that environment of origin would be a good predictor of thermal preference and critical thermal limits. To test this, Branchiopodopsis tridens (Anostraca) and Leptestheria brevirostris (Spinicaudata) were collected from rock-pool habitats, while Streptocephalus cafer (Anostraca) and a Gondwanalimnadia sp. (Spinicaudata) were collected from pan habitats. In contrast to our hypothesis, taxonomic relatedness was a better predictor of CTmax and temperature preference than environment of origin. Spinicaudatans were significantly more tolerant of high temperatures than anostracans, with L. brevirostris and Gondwanalimnadia sp. median CTmax values of 45.1 °C and 44.1 °C, respectively, followed by S. cafer (42.8 °C) and B. tridens (41.4 °C). Neither environment or taxonomic relatedness were good predictors of CTmin trends, with B. tridens (0.9 °C) and Gondwanalimnadia sp. (2.1 °C) having the lowest median CTmin values, followed by L. brevirostris (3.4 °C) and S. cafer (3.6 °C). On the contrary, temperature preferences differed according to taxa, with spinicaudatans significantly preferring higher temperatures than anostracans. Leptestheria brevirostris and Gondwanalimnadia sp. both spent most time at temperatures 30–32 °C, S. cafer at 18–20 °C and B. tridens at 21–23 °C. Constrained thermal traits reported here suggest that the studied anostracans might be more susceptible to projected climatic warming than the spinicaudatans, irrespective of habitat type, however, these taxa may also compensate through phenotypic plasticity

    The complete mitogenome of the fairy shrimp Streptocephalus cafer (Lovén, 1847) (Crustacea: Branchiopoda: Anostraca) from an ephemeral pond in Botswana, southern Africa

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    Fairy shrimps (Anostraca) constitute an important component of seasonally aquatic habitats, but few complete mitochondrial genomes have been published for this group. Here, we report the mitogenome of a common southern African species, Streptocephalus cafer, from Botswana (accession number: MN720104). Low-coverage shotgun sequencing recovered two contigs 15653 bp and 1347 bp in length that are separated by a repetitive region of unknown length within the non-coding control region. The mitogenome’s GC content is 31.80%. Phylogenetic analysis using protein-coding genes confirms the sister taxon relationship of S. cafer with the only other congener whose mitogenome has been reconstructed to date, the Asian S. sirindhornae

    The complete mitogenome of an undescribed clam shrimp of the genus Gondwanalimnadia (Branchiopoda: Spinicaudata), from a temporary wetland in Central District, Botswana

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    Clam shrimps (Spinicaudata) are a widespread and diverse crustacean group that frequent temporary aquatic habitats, but few complete mitochondrial genomes have been published for this group. Here, we report the mitogenome of an undescribed Gondwanalimnadia species from Botswana. Raw sequences were assembled into a single circular genome with a total length of 15,663 bp. Thirteen protein-coding genes, 22 tRNAs, and 2 rRNAs were identified using the MITOS pipeline. The mitogenome’s GC content is 33.52%. Phylogenetic analysis using protein-coding genes confirmed that Gondwanalimnadia sp. is closely related to another member of the Limnadiidae, Limnadia lenticularis

    The complete mitogenome of Leptestheria brevirostris Barnard, 1924, a rock pool clam shrimp (Branchiopoda: Spinicaudata) from Central District, Botswana

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    Spinicaudatan clam shrimp are a widespread and diverse group of branchiopod crustaceans, yet few mitochondrial genomes have been published for this taxonomic group. Here, we present the mitogenome of Leptestheria brevirostris from a rock pool ecosystem in Botswana. Massively parallel sequencing of a single specimen facilitated the reconstruction of the species’ 15,579 bp circularized mitogenome. The reconstructed phylogenetic tree confirms that L. brevirostris forms a monophyletic group with other diplostracan branchiopods, and that these are the sister taxon to Notostraca. The mitogenome reconstructed here is the first to be reported from a leptestherid clam shrimp

    Global Matrix 4.0 Physical Activity Report Card Grades for Children and Adolescents: Results and Analyses From 57 Countries

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    Background: The Global Matrix 4.0 on physical activity (PA) for children and adolescents was developed to achieve a comprehensive understanding of the global variation in children’s and adolescents’ (5–17 y) PA, related measures, and key sources of influence. The objectives of this article were (1) to summarize the findings from the Global Matrix 4.0 Report Cards, (2) to compare indicators across countries, and (3) to explore trends related to the Human Development Index and geo-cultural regions. Methods: A total of 57 Report Card teams followed a harmonized process to grade the 10 common PA indicators. An online survey was conducted to collect Report Card Leaders’ top 3 priorities for each PA indicator and their opinions on how the COVID-19 pandemic impacted child and adolescent PA indicators in their country. Results: Overall Physical Activity was the indicator with the lowest global average grade (D), while School and Community and Environment were the indicators with the highest global average grade (C+). An overview of the global situation in terms of surveillance and prevalence is provided for all 10 common PA indicators, followed by priorities and examples to support the development of strategies and policies internationally. Conclusions: The Global Matrix 4.0 represents the largest compilation of children’s and adolescents’ PA indicators to date. While variation in data sources informing the grades across countries was observed, this initiative highlighted low PA levels in children and adolescents globally. Measures to contain the COVID-19 pandemic, local/international conflicts, climate change, and economic change threaten to worsen this situation

    Status and Trends of Physical Activity Surveillance, Policy, and Research in 164 Countries: Findings From the Global Observatory for Physical Activity—GoPA! 2015 and 2020 Surveys

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    Background: Physical activity (PA) surveillance, policy, and research efforts need to be periodically appraised to gain insight into national and global capacities for PA promotion. The aim of this paper was to assess the status and trends in PA surveillance, policy, and research in 164 countries. Methods: We used data from the Global Observatory for Physical Activity (GoPA!) 2015 and 2020 surveys. Comprehensive searches were performed for each country to determine the level of development of their PA surveillance, policy, and research, and the findings were verified by the GoPA! Country Contacts. Trends were analyzed based on the data available for both survey years. Results: The global 5-year progress in all 3 indicators was modest, with most countries either improving or staying at the same level. PA surveillance, policy, and research improved or remained at a high level in 48.1%, 40.6%, and 42.1% of the countries, respectively. PA surveillance, policy, and research scores decreased or remained at a low level in 8.3%, 15.8%, and 28.6% of the countries, respectively. The highest capacity for PA promotion was found in Europe, the lowest in Africa and low- and lower-middle-income countries. Although a large percentage of the world’s population benefit from at least some PA policy, surveillance, and research efforts in their countries, 49.6 million people are without PA surveillance, 629.4 million people are without PA policy, and 108.7 million live in countries without any PA research output. A total of 6.3 billion people or 88.2% of the world’s population live in countries where PA promotion capacity should be significantly improved. Conclusion: Despite PA is essential for health, there are large inequalities between countries and world regions in their capacity to promote PA. Coordinated efforts are needed to reduce the inequalities and improve the global capacity for PA promotion

    Emergent effects of light and temperature on hatching success of Streptocephalus cafer (Branchiopoda: Anostraca) resting eggs

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    Resting egg production is considered the most common form of dormancy in aquatic invertebrates. Given that many taxa at least partially terminate resting egg state using environmental cues, knowledge on environmental drivers of hatching success is important, particularly within the context of climate change and environmental degradation. Fairy shrimp (anostracans) are temporary wetland specialists that are reliant on resting egg production for population persistence. Temporary wetlands are common in many arid regions projected to experience increases in temperature, and in areas often compromised by human‐mediated activities. In this study, we assessed the combined effects of light and temperature on the hatching success of Streptocephalus cafer (Anostraca) dormant eggs from temporary wetlands in an arid environment. Both temperature and light altered hatching success, with emergent effects evident. Light caused a significant threefold increase in hatching success overall, while temperature effects were non‐linear, with hatching optimised at 27°C, and especially under light conditions. These results are discussed within the context of shifting climates and disturbances to temporary wetland ecosystems
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