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Cuento Caperucita en tiempos modernos
(2025) Araya Fonseca, Evelyn; Yee Bonilla, Johanna
El documento “Caperucita en tiempos modernos”, escrito por Évelyn Araya Fonseca, es un cuento que actualiza la historia clásica de Caperucita Roja al contexto contemporáneo. Narra cómo la protagonista aprende a mantenerse cerca de su abuelita y de su escuela mediante videollamadas y herramientas digitales, resaltando valores como la solidaridad, el cuidado familiar y el uso responsable de la tecnología. A través de un tono educativo y reflexivo, el texto invita a valorar la empatía, la convivencia y la importancia de adaptarse a los cambios de la vida moderna.
A morphological search for the sound mechanism of Hamadryas butterflies (Lepidoptera: Nymphalidae)
(Journal of Research on the Lepidoptera, 30(3-4):196-208, 1991, 1991) Monge Najera, Julián; Hernández Chavarría, Francisco
At least seven locations have been proposed for the sonic mechanism of Hamadryas butterflies, which has not been identified to date. Using light microscopy, five species of Hamadryas (including a “mute” population) were compared with Siproeta stelenes, Ancirtia fatima and Ectima thecla, which do not emit audible sound. Three macrostructures were found exclusively inHamadryas: the abdominal rami, and in the forewings, a hemispheric membrane in the costal cell and the swollen base of the subcostal vein. Only the third appears to be related to sound emission (possibly, percussion by clapping the wings). Thus, the forewings appear to be the most feasible location for the sound emission mechanism in Hamadryas.
Hundreds of genetic barcodes of the species-rich hydroid superfamily Plumularioidea (Cnidaria, Medusozoa) provide a guide toward more reliable taxonomy
(2018-12-20) Moura, Carlos J.; Lessios, Harilaos; Cortés Núñez, Jorge; Nizinski, Martha S.; Reed, John; Santos, Ricardo S.; Collins, Allen G.
Marine hydroids are important benthic components of shallow and deep waters worldwide, but their taxonomy is controversial because diagnostic morphological characters to categorize taxa are limited. Their genetic relationships are also little investigated. We tested taxonomic hypotheses within the highly speciose superfamily Plumularioidea by integrating a classical morphological approach with DNA barcoding of the 16S and COI mitochondrial markers for 659 and 196 specimens of Plumularioidea, respectively. Adding Genbank sequences, we inferred systematic relationships among 1,114 plumularioids, corresponding to 123 nominal species and 17 novel morphospecies in five families of Plumularioidea. We found considerable inconsistencies in the systematics of nominal families, genera and species. The families Kirchenpaueriidae and Plumulariidae were polyphyletic and the Halopterididae paraphyletic. Most genera of Plumularioidea are not monophyletic. Species diversity is considerably underestimated. Within our study, at least 10% of the morphologically-distinctive morphospecies are undescribed, and about 40% of the overall species richness is represented by cryptic species. Convergent evolution and morphological plasticity therefore blur systematic relationships. Additionally, cryptic taxa occur frequently in sympatry or parapatry, complicating correspondence with type material of described species. Sometimes conspecificity of different morphotypes was found. The taxonomy of hydroids requires continued comprehensive revision.
Observations of Litter Deposited in the Deep Waters of Isla del Coco National Park, Eastern Tropical Pacific
(2018-03-20) Naranjo Elizondo, Beatriz; Cortés Núñez, Jorge
Marine debris is recognized as a major threat to biodiversity and can be found ubiquitously even in remote regions, including deep-sea environments. Isla del Coco National Park is known as one of the best protected areas around the world, a preferred diving destination, and is also renowned for large aggregations of pelagic species that attract illegal commercial fisheries. Despite its pristine reputation, this study demonstrates that anthropogenic debris can affect this remote and well protected area. Images of marine debris weretakenusingtheDeepSeesubmersible,mainlyplasticlitter from fishing gear were found between 200 and 350m depth. A total of 40 items of debris were found in 5.48%of365dives,60%oftheitemswereplastics,andlocalboatandfishingactivities provided mostoflitter. Our aim with this research is to raise awareness about the potential problem of solid wastes and fishing gear deposited in the deep environments of Isla del CocoNational Park and to explore the potential implications for the ecological integrity of this protected area, including ghost fishing and the possible ingestion of pollutants. These results provide useful management information for the area, especially if one considers the constant pressure of illegal fishing and tourism at Isla del Coco National Park.
New sighting of seagrasses in the Eastern Tropical Pacific (Bahía Potrero, Costa Rica)
(2018-07-22) Samper Villarreal, Jimena; Rojas Ortega, Gustavo; Vega Alpízar, Jose Luis; Cortés Núñez, Jorge
Seagrass meadows provide a multitude of ecosystem services, yet they are currently threatened and declining worldwide due to anthropogenic impacts. Current knowledge of seagrass presence in the Eastern Tropical Pacific (ETP) is scarce, in part due to challenges in finding the small seagrass species found and their dynamic and possibly ephemeral nature, with only very limited reports of currently extant meadows. Here, we characterize seagrasses at a new location, Bahía Potrero, on the northern Pacific coast of Costa Rica. Seagrasses were sighted at this location on four occasions between 2015 and 2017. Two seagrass species were found, Halophila baillonis and Halodule beaudettei. Seagrasses were present at ∼ 3–6 m depth at mean sea level (local tidal range ∼ 3 m). Biomass and sediment cores were collected in 2017, total biomass was 3.9 ± 4.0 g DW m−2 and density 569 ± 493 shoots m−2 . Leaf length was 1.1 ± 0.29 cm, width 0.5 ± 0.08 cm, and area 1.4 ± 0.67 cm2 . Above ground biomass δ13C was -11.7 ± 0.8‰ and δ15N 5.4 ± 0.8‰, while below ground was -11.7 ± 1.3‰ and 5.3 ± 0.8‰. Sediment δ13C was -21.2 ± 0.6‰ and δ15N was 8.6 ± 0.4‰. Sediments were dominated by very fine sand, with 1.6 ± 0.3% organic carbon content and 23.0 ± 7.9% inorganic carbon. Carbon content standardized to 10 cm sediment depth was 20.5 ± 5.1 Mg OC ha-1 and 295.1 ± 109.8 Mg IC ha-1. Given the numerous threats that seagrasses are under and the lack of information on seagrasses in the ETP it is critical to increase our knowledge on seagrasses in this region for adequate management and conservation initiatives.