1,535 research outputs found
Evolutionary diversification and historical biogeography of orchidaceae in Central America with emphasis on Costa Rica and Panama
In this thesis, I targeted the orchid genus Lepanthes, one of the six genera of angiosperms that surpasses 1,000 species in the Neotropics, as a study model to investigate the evolutionary processes that promoted species diversifications. To investigate this, we improved the taxonomy of the group integrating a solid phylogenetic framework with morphological evolution, assessing inter-specific relationships in species complexes with hundreds of DNA markers using anchored hybrid enrichment approach, and describing new species. In addition, we addressed the pollination of Trichosalpinx through the study of floral anatomy, pollinator behavior, and floral traits. Trichosalpinx flowers are pollinated exclusively by female biting midges that are attracted by the small quantities of proteins secreted on the flowers. Finally, we inferred the biogeographical history and diversification dynamics of the two largest Neotropical orchid groups (Cymbidieae and Pleurothallidinae), using densely sampled phylogenies coupled with geological datasets and discussed the impact of biogeographical events and orogeny on the species richness of Lepanthes. Species diversification is correlated with Andean orogeny, and multiple migrations and recolonizations across the Andes indicate that mountains do not constrain orchid dispersal over long timescales. This thesis provides new insights into the complex evolution of one of the most species-rich angiosperm.Leiden University/[]//Países BajosCentro de Biodiversidad Naturalis/[]//Países BajosUniversidad de Costa Rica/[]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Jardín Botánico Lankester (JBL
A new species of Eurystyles (Orchidaceae: Spiranthinae) from Costa Rica
Eurystyles comprises about 23 species ranging from Mexico to northernArgentina. Six species are recognized in Mexico and Central America and three in Costa Rica. A new species, named E. uxoris, is here described and illustrated based on Costa Rican material. The species is similar to Eurystyles auriculata and E. standleyi, however, it differs by the smaller plants up to 3 cm tall, smaller leaves of less than 1.6 cm long, flowers with brown dorsal sepal and brown lip apex, petals callose or thickened at apex, and a pandurate lip. Information about distribution, habitat, ecology, etymology and phenology of the new species is provided. An updated key to the Costa Rican species of Eurystyles is presented.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Jardín Botánico Lankester (JBL
Environmental Explanations of Central American Migration: Challenges and Recommendations for the Development of Public Policies
Environmental Explanations of Central American Migration: Challenges and Policy Recommendations
In this report, the authors argue that when countries and relevant stakeholders do not prioritize disaster preparedness and foster community resilience, extreme climate events can deplete people’s material and socioeconomic well-being. This results in internal displacement as people seek economic opportunities and social protection, which may exacerbate conflict and social tension in the cities they move to. Ultimately, this helps explain one unexamined consideration driving migration to the United States from the Northern Triangle countries.https://digitalcommons.fiu.edu/jgi_research/1038/thumbnail.jp
Regional Migration Governance in the Americas: The Los Angeles Declaration on Protection and Migration\u27s Challenges and Opportunities
As the LA Declaration enters a new phase of maturation, it is imperative for the hemisphere to intensify efforts to overcome coordination and communication challenges among countries and levels of government. Addressing existing barriers, such as securing sustainable funding among others, is essential for countries and agencies to tackle specific migration challenges effectively. Additionally, regional policymakers must prioritize investments in migration to achieve broader societal objectives in the medium and long termhttps://digitalcommons.fiu.edu/jgi_research/1053/thumbnail.jp
Notes on facultative use of bat-modified “leaf tents” by Agalychnis Red-eyed treefrogs (Anura: Hylidae)
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