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1.
New Phytol ; 236(4): 1572-1583, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36068995

RESUMO

The evolution of hummingbird pollination is common across angiosperms throughout the Americas, presenting an opportunity to examine convergence in both traits and environments to better understand how complex phenotypes arise. Here we examine independent shifts from bee to hummingbird pollination in the Neotropical spiral gingers (Costus) and address common explanations for the prevalence of transitions from bee to hummingbird pollination. We use floral traits of species with observed pollinators to predict pollinators of unobserved species and reconstruct ancestral pollination states on a well-resolved phylogeny. We examine whether independent transitions evolve towards the same phenotypic optimum and whether shifts to hummingbird pollination correlate with elevation or climate. Traits predicting hummingbird pollination include small flower size, brightly colored floral bracts and the absence of nectar guides. We find many shifts to hummingbird pollination and no reversals, a single shared phenotypic optimum across hummingbird flowers, and no association between pollination and elevation or climate. Evolutionary shifts to hummingbird pollination in Costus are highly convergent and directional, involve a surprising set of traits when compared with other plants with analogous transitions and refute the generality of several common explanations for the prevalence of transitions from bee to hummingbird pollination.


Assuntos
Costus , Polinização , Abelhas , Animais , Néctar de Plantas , Aves , Flores/genética
2.
Proc Natl Acad Sci U S A ; 116(20): 9903-9912, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31036662

RESUMO

Tropical agriculture is a major driver of biodiversity loss, yet it can provide conservation opportunities, especially where protected areas are inadequate. To investigate the long-term biodiversity capacity of agricultural countryside, we quantified bird population trends in Costa Rica by mist netting 57,255 birds of 265 species between 1999 and 2010 in sun coffee plantations, riparian corridors, secondary forests, forest fragments, and primary forest reserves. More bird populations (69) were declining than were stable (39) or increasing (4). Declines were common in resident, insectivorous, and more specialized species. There was no relationship between the species richness of a habitat and its conservation value. High-value forest bird communities were characterized by their distinct species composition and habitat and dietary functional signatures. While 49% of bird species preferred forest to coffee, 39% preferred coffee to forest and 12% used both habitats, indicating that coffee plantations have some conservation value. Coffee plantations, although lacking most of the forest specialists, hosted 185 bird species, had the highest capture rates, and supported increasing numbers of some forest species. Coffee plantations with higher tree cover (7% vs. 13%) had more species with increasing capture rates, twice as many forest specialists, and half as many nonforest species. Costa Rican countryside habitats, especially those with greater tree cover, host many bird species and are critical for connecting bird populations in forest remnants. Diversified agricultural landscapes can enhance the biodiversity capacity of tropical countryside, but, for the long-term persistence of all forest bird species, large (>1,000 ha) protected areas are essential.


Assuntos
Aves , Conservação dos Recursos Naturais , Ecossistema , Agricultura , Animais , Coffea , Costa Rica , Dinâmica Populacional , Clima Tropical
3.
Am J Bot ; 108(9): 1635-1645, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34541661

RESUMO

PREMISE: Prior efforts have shown that continents harbor a greater proportion of mycorrhizal hosts than on islands. However, in the Hawaiian Islands, estimates of the proportion of mycorrhizal plant species are higher than on continents (>90%), but there are few studies to support this claim. Concurrently, Hawaii's flora faces some of the greatest global risks of extinction, and significant efforts are aimed at restoring native vegetation. Arbuscular mycorrhizal (AM) fungi have been shown to improve plant restoration success, but little work has been done in Hawaii to understand the extent of mycorrhizal associations among native plant populations. METHODS: We surveyed 35 native Hawaiian plant species in the wild, focusing on plant species that are reared for reintroduction. Roots from wild individuals were collected from 10 sites on Oahu to determine degree of mycorrhizal fungal colonization and how this varies across host populations. RESULTS: Of the species surveyed, 97% had evidence of mycorrhizal colonization, including 25 endemic and nine indigenous species from 23 families. The mycorrhizal status of 22 of the species surveyed was unknown before this study. For four species, the degree of colonization by AM fungi differed among sites, and these differences corresponded with variations in precipitation and temperature. CONCLUSIONS: The high incidence of mycorrhizal colonization provides evidence that island flora can actually harbor more mycorrhizal hosts than species on mainlands and that future reintroduction projects should consider the potentially important roles of AM fungi for success of these hosts in the wild.


Assuntos
Micorrizas , Havaí , Incidência , Raízes de Plantas , Plantas , Simbiose
4.
Biol Conserv ; 256: 108984, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36531528

RESUMO

COVID-19 has altered many aspects of everyday life. For the scientific community, the pandemic has called upon investigators to continue work in novel ways, curtailing field and lab research. However, this unprecedented situation also offers an opportunity for researchers to optimize and further develop available field methods. Camera traps are one example of a tool used in science to answer questions about wildlife ecology, conservation, and management. Camera traps have long battery lives, lasting more than a year in certain cases, and photo storage capacity, with some models capable of wirelessly transmitting images from the field. This allows researchers to deploy cameras without having to check them for up to a year or more, making them an ideal field research tool during restrictions on in-person research activities such as COVID-19 lockdowns. As technological advances allow cameras to collect increasingly greater numbers of photos and videos, the analysis techniques for large amounts of data are evolving. Here, we describe the most common research questions suitable for camera trap studies and their importance for biodiversity conservation. As COVID-19 continues to affect how people interact with the natural environment, we discuss novel questions for which camera traps can provide insights on. We conclude by summarizing the results of a systematic review of camera trap studies, providing data on target taxa, geographic distribution, publication rate, and publication venues to help researchers planning to use camera traps in response to the current changes in human activity.

5.
Am Nat ; 188 Suppl 1: S1-7, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27513908

RESUMO

Scientists have been observing the natural world for centuries and have long been intrigued by the high biodiversity and complexity of the tropics. They also usually had North American or European-in other words, outsider-perspectives and frequently concluded that the tropics were qualitatively different from the temperate regions in their ecology, evolution, and behavior. In particular, the tropics were seen as having a more benign abiotic environment, which in turn fostered more complex biotic relationships, with increased competition and other interactions. This may or may not be the case. Regardless, these ideas establish the temperate regions of the world as a kind of model system, a norm to which the tropics are compared and seen as different or unusual. The tropics are warmer or more diverse, rather than the temperate zone being cooler or less diverse. Such an attitude makes it difficult both to appreciate the scope of variation in nature and to develop accurate and general models for ecological and evolutionary processes.


Assuntos
Biodiversidade , Ecologia , Modelos Biológicos , Animais , Clima Tropical
6.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230110, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38705184

RESUMO

Night-time light can have profound ecological effects, even when the source is natural moonlight. The impacts of light can, however, vary substantially by taxon, habitat and geographical region. We used a custom machine learning model built with the Python package Koogu to investigate the in situ effects of moonlight on the calling activity of neotropical forest katydids over multiple years. We prioritised species with calls that were commonly detected in human annotated data, enabling us to evaluate model performance. We focused on eight species of katydids that the model identified with high precision (generally greater than 0.90) and moderate-to-high recall (minimum 0.35), ensuring that detections were generally correct and that many calls were detected. These results suggest that moonlight has modest effects on the amount of calling, with the magnitude and direction of effect varying by species: half of the species showed positive effects of light and half showed negative. These findings emphasize the importance of understanding natural history for anticipating how biological communities respond to moonlight. The methods applied in this project highlight the emerging opportunities for evaluating large quantities of data with machine learning models to address ecological questions over space and time. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Assuntos
Florestas , Aprendizado de Máquina , Vocalização Animal , Animais , Luz
7.
Zookeys ; 1044: 721-727, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34183889

RESUMO

A very large, new, and distinctive species of Conotrachelus Dejean is described from Área de Conservación Guanacaste, Costa Rica. Conotrachelus terryerwini sp. nov. (type locality Volcan Orosi, Estación Biológica Maritza, Guanacaste, Costa Rica) is described and named in honor of Terry L. Erwin (1940-2020), famed carabidologist and biodiversity champion. This majestic species is easily distinguished by its large body size (15-20 mm) and extremely long rostrum (especially in females).

8.
PeerJ ; 5: e4020, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29134155

RESUMO

There has been very little effort to incorporate foliar microbiomes into plant conservation efforts even though foliar endophytes are critically important to the fitness and function of hosts. Many critically endangered plants that have been extirpated from the wild are dependent on regular fungicidal applications in greenhouses that cannot be maintained for remote out-planted populations, which quickly perish. These fungicides negatively impact potentially beneficial fungal symbionts, which may reduce plant defenses to pathogens once fungicide treatments are stopped. Using the host/parasite system of Phyllostegia kaalaensis and Neoerysiphe galeopsidis, we conducted experiments to test total foliar microbiome transplants from healthy wild relatives onto fungicide-dependent endangered plants in an attempt to mitigate disease and reduce dependency on fungicides. Plants were treated with total microbiome transplants or cultured subsets of this community and monitored for disease severity. High-throughput DNA screening of fungal ITS1 rDNA was used to track the leaf-associated fungal communities and evaluate the effectiveness of transplantation methods. Individuals receiving traditionally isolated fungal treatments showed no improvement, but those receiving applications of a simple leaf slurry containing an uncultured fungal community showed significant disease reduction, to which we partially attribute an increase in the mycoparasitic Pseudozyma aphidis. These results were replicated in two independent experimental rounds. Treated plants have since been moved to a native habitat and, as of this writing, remain disease-free. Our results demonstrate the effectiveness of a simple low-tech method for transferring beneficial microbes from healthy wild plants to greenhouse-raised plants with reduced symbiotic microbiota. This technique was effective at reducing disease, and in conferring increased survival to an out-planted population of critically endangered plants. It was not effective in a closely related plant. Plant conservation efforts should strive to include foliar microbes as part of comprehensive management plans.

9.
Rev. biol. trop ; Rev. biol. trop;64(1): 147-156, ene.-mar. 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-843267

RESUMO

ResumenEl estudio de la actividad de una revista resulta esencial para conocer la evolución de sus características a lo largo del tiempo. En este trabajo se realiza un análisis bibliométrico de la Revista de Biología Tropical, utilizando como fuente la base de datos Web of Science (ThomsonReuters), entre los años 2003-2012. El objetivo del trabajo es describir las principales características de la producción de la revista y analizar el desarrollo de la colaboración y el impacto en la última década. Se estudia la colaboración entre autores, instituciones y países y su vinculación con las citas recibidas. Se han obtenido indicadores de producción (número de documentos por año, institución y país), colaboración (índice de co-autoría, colaboración entre centros y países) e impacto (factor de impacto, posición en el Journal Citation Report, citas recibidas). Los resultados muestran que en el período estudiado la revista ha publicado 1 473 artículos. Predominan los documentos en inglés y español -por partes iguales- y los principales países de procedencia son México, Costa Rica, Venezuela y Colombia. La Universidad de Costa Rica es la institución que produce la mayor parte de los artículos, con un 17 % de los documentos, seguida de la Universidad Autónoma de México y la Universidad de Puerto Rico. Se evidencia que la colaboración entre autores, instituciones y países ha crecido constantemente en la última década. El índice de coautoría ha sido de 3.07 autores por documento. Un 63 % de las publicaciones se han realizado en colaboración entre 2 o más instituciones y un 22 % en colaboración internacional. Las relaciones de colaboración más frecuentes se producen entre Costa Rica y Estados Unidos. En cuanto al impacto de la revista, dentro de la categoría Biology el factor de impacto ha tenido oscilaciones, alcanzando su máximo valor en 2012 (FI JCR = 0.553). Se ha detectado que el 10 % de los documentos más citados concentra la mitad de las citas recibidas por la revista y tienen un porcentaje de colaboración internacional muy superior a la media de la revista. Los principales países usuarios fueron Estados Unidos, Brasil, México, Argentina y Costa Rica, de quienes proviene la mayor citación de la revista. Los datos muestran una tendencia creciente a la colaboración entre autores, instituciones y países y una relación directa entre el incremento de esta colaboración y el impacto recibido.


Abstract:The activity analysis of a scientific journal is relevant to know the evolution of its characteristics over time. In this paper, results of a bibliometric study of the Revista de Biología Tropical/International Journal of Tropical Biology and Conservation (Costa Rica) are presented. The goal of this study was to describe the main characteristics of its scientific production, and analyze its level of collaboration and its impact between the years 2003-2012. Data was derived from the Web of Science (Thomson-Reuters), and the relationship among authors and coauthors, institutions and countries, and their links with the citations received were analyzed for that period. Descriptive statistics about production (number of documents per year, institution and country), collaboration (authorship index, collaboration among institutions and countries) and impact (IF, position in JCR and number of citations received) were collected. Results showed that the journal has published 1 473 papers in this period, in similar proportions English and Spanish. Mexico, Costa Rica, Venezuela and Colombia are the most common countries of origin, with the Universidad of Costa Rica, Universidad Autónoma de Mexico and the University of Puerto Rico as the most common leader institutions. Collaboration between authors, institutions and countries has shown an increasing trend over the last decade. The co-author index was 3.07 per document, 63 % of publications included 2 or more institutions, and 22 % of the papers were product of international collaboration. The most common collaboration link was between Costa Rica and the United States of America. The impact factor has been oscillating during this last decade, reaching a maximum in 2012 (IF JCR = 0.553). Besides, 10 % of the most cited papers concentrated half of the citations received by the journal, and have a very high number of citations, compared with the journal mean. The main countries that cite the journal were USA, Brazil, Mexico, Argentina and Costa Rica. Data showed an increasing collaboration between authors, institutions and countries, and a direct relationship between the increase of this collaboration and the received impact.


Assuntos
Humanos , Publicações Periódicas como Assunto/estatística & dados numéricos , Biologia/estatística & dados numéricos , Bibliometria , Autoria , Costa Rica
10.
Rev. biol. trop ; Rev. biol. trop;59(3): 983-992, Sept. 2011. tab
Artigo em Inglês | LILACS | ID: lil-638133

RESUMO

Tropical biologists study the richest and most endangered biodiversity in the planet, and in these times of climate change and mega-extinctions, the need for efficient, good quality research is more pressing than in the past. However, the statistical component in research published by tropical authors sometimes suffers from poor quality in data collection; mediocre or bad experimental design and a rigid and outdated view of data analysis. To suggest improvements in their statistical education, we listed all the statistical tests and other quantitative analyses used in two leading tropical journals, the Revista de Biología Tropical and Biotropica, during a year. The 12 most frequent tests in the articles were: Analysis of Variance (ANOVA), Chi-Square Test, Student’s T Test, Linear Regression, Pearson’s Correlation Coefficient, Mann-Whitney U Test, Kruskal-Wallis Test, Shannon’s Diversity Index, Tukey’s Test, Cluster Analysis, Spearman’s Rank Correlation Test and Principal Component Analysis. We conclude that statistical education for tropical biologists must abandon the old syllabus based on the mathematical side of statistics and concentrate on the correct selection of these and other procedures and tests, on their biological interpretation and on the use of reliable and friendly freeware. We think that their time will be better spent understanding and protecting tropical ecosystems than trying to learn the mathematical foundations of statistics: in most cases, a well designed one-semester course should be enough for their basic requirements. Rev. Biol. Trop. 59 (3): 983-992. Epub 2011 September 01.


Los biólogos tropicales estudian la biodiversidad más rica y amenazada del planeta, y en estos tiempos de cambio climático y mega-extinción, la necesidad de investigación de buena calidad es más acuciante que en el pasado. Sin embargo, el componente estadístico en la investigación publicada por los autores tropicales adolece a veces de baja calidad en la toma de datos, mal diseño experimental y una visión anticuada del análisis de datos. Para sugerir mejoras en la enseñanza de la estadística, hicimos una lista de todas las pruebas estadísticas y otros análisis cuantitativos aplicados en dos de las principales revistas tropicales, la Revista de Biología Tropical y Biotropica, durante un año. Las 12 pruebas más frecuentes en los artículos fueron: Análisis de Varianza (ANDEVA), Chi-cuadrado, t de Student, Regresión lineal, Coeficiente de Correlación de Pearson, U de Mann-Whitney, Kruskal-Wallis, Índice de diversidad de Shannon, Prueba de Tukey, Análisis de Conclomerados, Correlación de Spearman y Análisis de Componentes Principales. Concluimos que la enseñanza de la estadística para los biólogos tropicales debe abandonar el viejo plan de estudios basado en el lado matemático de la estadística y concentrarse en (1) la correcta selección de estos y otros procedimientos y pruebas, (2) su interpretación biológica y (3) la utilización de programas de fácil uso. En la mayoría de los casos, un curso bien diseñado de un semestre bastaría para sus necesidades básicas.


Assuntos
Humanos , Biologia/educação , Pesquisadores/educação , Pesquisa/educação , Estatística como Assunto/educação , Interpretação Estatística de Dados , Pesquisa/estatística & dados numéricos , Clima Tropical
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