Epizoocoría por medio de iguanas en el bosque seco: ¿un mecanismo de dispersión de semillas pasado por alto?

The role of animals as seed dispersal vectors is widely acknowledged, including dispersal by reptiles (saurochory). Most reports of saurochory have been via endozoochory, through feces deposition. We present the first evidence of epizoochory in Iguanas from a dry forest in Colombia via seeds attached to the snout. Our results show that seeds of a cactus Melocactus curvispinus ingested by iguana suffers from their passage through the digestive tract while seeds transported while attached to the snout germinate faster and in higher numbers. Our data suggest that we may have overlooked an alternative means of seed dispersal by lizards that does not comprise a passage through their digestive tract, and that deserves further attention for the understanding of dry forest ecology.El papel que juegan los animales como vectores en la dispersión de semillas es extensamente reconocido, incluso la dispersión por reptiles, mejor conocida como saurocoría. La mayoría de los reportes de saurocoria han sido a través de endozoocoria, es decir, el transporte interno de semillas que han sido ingeridas y luego depositadas con las heces. Presentamos la primera evidencia de epizoocoría en Iguana iguana por medio del transporte externo de semillas adheridas a su hocico observado en el bosque seco de Tatacoa, Colombia. Nuestros resultados muestran que las semillas del cactus Melocactus curvispinus ingeridos son probablemente dañadas al pasar por el tracto digestivo de la iguana, mientras que las semillas transportadas externamente germinan más rápido y en mayor número. Nuestros datos sugieren que es posible que hayamos estado ignorando un mecanismo alternativo de dispersión de semillas por lagartos que no comprende el paso a través del tracto digestivo, lo cual merece mayor atención para una mejor comprensión de la ecología del bosque seco

Propuesta para la creación del departamento de recursos humanos y reestructuración de la Empresa SEMILSA del Cantón Milagro, con enfoque de inteligencia emocional para el talento humano.

La inseguridad en la actualidad mantiene un alto índice de crecimiento, razón por la cual se han formado entidades de guardianía y custodia de bienes, para salvaguardar la vida y estabilidad de una parte de la sociedad, por ello, se tomó como objetivo de investigación a la empresa SEMILSA, entidad que mantiene un posicionamiento respetable en este mercado, más sin embargo, presenta deficiencias en la parte administrativa suscitando cambien inconvenientes laborales con el personal de guardianía, razón por la cual he desarrollado todo el contenido de la propuesta a través de cinco capítulos, teniendo como primer paso el detalle de la problemática sus causas, efectos, objetivos, delimitación formulación Y su correspondiente justificación de la investigación, posteriormente se ha establecido información histórica de la empresa para conocer sus inicios hasta la actualidad, además se encontrará toda la información necesaria para una mejor comprensión del trabajo investigativo, respondiendo efectivamente la formulación y sistematización del problema a través de la hipótesis y variables. El marco metodológico está compuesto por los tipos de investigación que se aplicaron para fundamentar la propuesta, en donde se determinó el universo, para el cálculo de la muestra utilizando la herramienta investigativa conocida como la encuesta, una vez obtenidos los datos de la encuesta se procedió a realizar la interpretación de los resultados es decir la recolección, tabulación y análisis del instrumento investigativo, donde se constató que el talento humano no tiene una adecuada formación profesional motivo por el cual se planteó la reestructuración administrativa de inteligencia emocional dirigido al personal, Se realizó la SEMILSA, con enfoque a la inteligencia emocional dirigido al personal. Se realizó la reestructuración de la misión, visión, objetivos y organigrama estructural, además se realizó un comparativo del balance general y estados de pérdidas y ganancias, demostrando así un índice de rentabilidad con esta propuesta, que beneficiara directamente a esta empresa así mismo a las autoras del proyect

The Role That Asexual Reproduction Plays in the Regeneration of Tropical Piper Shrubs: Habitat Differences and Genetic Consequences

148 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007.Asexual reproduction is a common, but little explored characteristic of many tropical plants with a variety of life-histories and habitat requirements. My dissertation research examined the ecological correlates and population genetic consequences of asexual reproductive success in five co-occurring Piper species using a combination of field experiments and molecular approaches. Working at the Barro Colorado Nature Monument (BCNM) Panama, I found that shade-tolerant species use asexual reproduction more often than do light-demanding species. Further, I showed that all Piper populations contain high genetic diversity regardless of the frequency of asexual reproduction in the population, and that these values of genetic diversity were higher than values found in most clonal plants in non-tropical ecosystems, but are similar to other clonal tropical plant species. Factors such as the accumulation of somatic mutations, habitat heterogeneity, and density dependent mortality, may be playing an important role in maintaining genetic diversity, despite high levels of asexual recruitment. I also integrated spatial geographic data with spatial genetic data and found that more than 50% of neighboring plants were close relatives and clones. I hypothesize that the strong spatial genetic structure found in this genus is the result of clumped dispersal of genetically related seeds and of a lack of overlap in the feeding territories of their seed dispersal agents, Carollia bats. Finally, one of the most striking findings of this research is that gene flow in these five Piper shrub species is generally more restricted than for tropical tree species. Limited gene flow, localized clonal spread and genetic drift could favor the establishment of small reproductively isolated populations, potentially leading to the speciation of some of the >1000 species of Piper currently present in the Tropics.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Body size, loading capacity and rate of reproduction in the communal bee Andrena agilissima (Hymenoptera; Andrenidae)

In bees, body size may be particularly important in determining the loading capacity, and consequently the rate of reproduction. We studied a population of Andrena agilissima (Hymenoptera: Andrenidae) in Italy, weighing provisioning females, load being carried and pollen provisions. We found no correlation between adult body size and loading capacity. Weight of pollen collected per trip did not vary across the day, while weight of nectar collected increased in the afternoon. The amount of nectar being carried was independent of the amount of pollen. The A. agilissima rate of reproduction resulted in less than 1 provision mass produced per day (3.6 offspring/female per season). This result is consistent with observations in other Andrena species which suggests a phylogenetic constraint in the rate of reproduction that merits further study

Restaurando el páramo y sembrando paz

textocomputadorarecurso en línea"El páramo de Sumapaz es un páramo extenso y silencioso, cuya neblina oculta muchos misterios y biodiversidad por descubrir. Este páramo, el más grande del mundo, es también, en términos biológicos, el menos conocido. Años de conflicto armado lo volvieron inaccesible a la mayoría de las personas y a la ciencia. Sin embargo, hoy se respiran vientos de cambio, y la prueba más evidente de ello es que los militares, que por años lo patrullaron y defendieron de los diversos frentes de las FARC, comienzan a imaginarse un futuro diferente con ellos como guardaparques, protectores de la biodiversidad, e incluso restauradores.

Epizoochory in dry forest iguanas: an overlooked seed dispersal mechanism?

The role of animals as seed dispersal vectors is widely acknowledged, including dispersal by reptiles (saurochory). Most reports of saurochory have been via endozoochory, through feces deposition. We present the first evidence of epizoochory in Iguanas from a dry forest in Colombia via seeds attached to the snout. Our results show that seeds of a cactus Melocactus curvispinus ingested by iguana suffers from their passage through the digestive tract while seeds transported while attached to the snout germinate faster and in higher numbers. Our data suggest that we may have overlooked an alternative means of seed dispersal by lizards that does not comprise a passage through their digestive tract, and that deserves further attention for the understanding of dry forest ecology

Epizoocoría por medio de iguanas en el bosque seco: ¿un mecanismo de dispersión de semillas pasado por alto?

The role of animals as seed dispersal vectors is widely acknowledged, including dispersal by reptiles (saurochory). Most reports of saurochory have been via endozoochory, through feces deposition. We present the first evidence of epizoochory in Iguanas from a dry forest in Colombia via seeds attached to the snout. Our results show that seeds of a cactus Melocactus curvispinus ingested by iguana suffers from their passage through the digestive tract while seeds transported while attached to the snout germinate faster and in higher numbers. Our data suggest that we may have overlooked an alternative means of seed dispersal by lizards that does not comprise a passage through their digestive tract, and that deserves further attention for the understanding of dry forest ecology.El papel que juegan los animales como vectores en la dispersión de semillas es extensamente reconocido, incluso la dispersión por reptiles, mejor conocida como saurocoría. La mayoría de los reportes de saurocoria han sido a través de endozoocoria, es decir, el transporte interno de semillas que han sido ingeridas y luego depositadas con las heces. Presentamos la primera evidencia de epizoocoría en Iguana iguana por medio del transporte externo de semillas adheridas a su hocico observado en el bosque seco de Tatacoa, Colombia. Nuestros resultados muestran que las semillas del cactus Melocactus curvispinus ingeridos son probablemente dañadas al pasar por el tracto digestivo de la iguana, mientras que las semillas transportadas externamente germinan más rápido y en mayor número. Nuestros datos sugieren que es posible que hayamos estado ignorando un mecanismo alternativo de dispersión de semillas por lagartos que no comprende el paso a través del tracto digestivo, lo cual merece mayor atención para una mejor comprensión de la ecología del bosque seco

High heat tolerance in plants from the Andean highlands: Implications for paramos in a warmer world.

Tropical plant species are expected to have high heat tolerance reflecting phenotypic adjustments to warm regions or their evolutionary adaptation history. However, tropical highland specialists adapted to the colder temperatures found in the highlands, where short and prostrated vegetation decouples plants from ambient conditions, could exhibit different upper thermal limits than those of their lowland counterparts. Here we evaluated leaf heat tolerance of 21 tropical alpine paramo species to determine: 1) whether species with restricted distribution (i.e., highland specialists) have lower heat tolerance and are more vulnerable to warming than species with widespread distribution; 2) whether different growth forms have different heat tolerance; and 3) whether species height (i.e., microhabitat) influences its heat tolerance. We quantified heat tolerance by evaluating T50, which is the temperature that causes a reduction in 50% of initial Fv/Fm values and reflects an irreversible damage to the photosynthetic apparatus. Additionally, we estimated the thermal safety margins as the difference between T50 and the maximum leaf temperature registered for the species. All species presented high T50 values ranging between 45.4°C and 53.9°C, similar to those found for tropical lowland species. Heat tolerance was not correlated with species distributions or plant height, but showed a strong relationship with growth form, with rosettes having the highest heat tolerance. Thermal safety margins ranged from 12.1 to 31.0°C. High heat tolerance and broad thermal safety margins suggest low vulnerability of paramo species to warming as long as plants are capable of regulating the leaf temperature within this threshold. Whether paramo plants would be able to regulate leaf temperature if drought episodes become more frequent and transpirational cooling is compromised is the next question that needs to be answered

Habitat preference and vulnerability to drought of three Hypericum species of the páramo

Background: Páramos are tropical alpine ecosystems where climate change is expected to cause yet unknown consequences for plant growth, ecosystem structure, ecosystem function and the provision of ecosystem services. Aim: To quantify the relationship between environmental factors (abiotic and biotic) and the spatial distribution of three common Hypericum species in the páramo and their physiological vulnerability to drought. Methods: We recorded soil water content, soil temperature, and vegetation cover in 10 plots along a moisture gradient. Additionally, we measured a series of physiological traits associated with the risk of drought-induced mortality. Results: We found that H. goyanesii and H. juniperinum mainly grew in areas with high soil water content, and similar high vegetation cover. These two species had wider xylem vessels, showed anisohydric behaviour and were equally vulnerable to cavitation with low safety margins against hydraulic failure. H. mexicanum grew in places with less vegetation cover, lower soil water content, and higher soil temperatures. H. mexicanum showed a different strategy that probably allows it to thrive in these conditions; it maintains high values of water potential at noon and has narrower xylem vessels, making it less vulnerable to cavitation. Conclusion: The distribution of the three Hypericum species in the páramo responds essentially to soil water content, in line with the physiological mechanisms of the species to cope with water deficit. Hypericum species from moist habitats could decline if longer drought episodes become more common in the future