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Functional traits can determine pairwise species interactions, such as those between plants and pollinators. However, the effects of biogeography and evolutionary history on trait-matching and trait-mediated resource specialization remain poorly understood.We compiled a database of 93 mutualistic hummingbird-plant networks (including 181 hummingbird and 1,256 plant species), complemented by morphological measures of hummingbird bill and floral corolla length. We divided the hummingbirds into their principal clades and used knowledge on hummingbird biogeography to divide the networks into four biogeographical regions: Lowland South America, Andes, North & Central America, and the Caribbean islands. We then tested: (a) whether hummingbird clades and biogeographical regions differ in hummingbird bill length, corolla length of visited flowers and resource specialization, and (b) whether hummingbirds' bill length correlates with the corolla length of their food plants and with their level of resource specialization.Hummingbird clades dominated by long-billed species generally visited longer flowers and were the most exclusive in their resource use. Bill and corolla length and the degree of resource specialization were similar across mainland regions, but the Caribbean islands had shorter flowers and hummingbirds with more generalized interaction niches. Bill and corolla length correlated in all regions and most clades, that is, trait-matching was a recurrent phenomenon in hummingbird-plant associations. In contrast, bill length did not generally mediate resource specialization, as bill length was only weakly correlated with resource specialization within one hummingbird clade (Brilliants) and in the regions of Lowland South America and the Andes in which plants and hummingbirds have a long co-evolutionary history. Supplementary analyses including bill curvature confirmed that bill morphology (length and curvature) does not in general predict resource specialization.These results demonstrate how biogeographical and evolutionary histories can modulate the effects of functional traits on species interactions, and that traits better predict functional groups of interaction partners (i.e. trait-matching) than resource specialization. These findings reveal that functional traits have great potential, but also key limitations, as a tool for developing more mechanistic approaches in community ecology.A free Plain Language Summary can be found within the Supporting Information of this article.

El monitoreo biológico es esencial para comprender la dinámica poblacional, los procesos ecológicos y los problemas emergentes. En este estudio determinamos la riqueza y abundancia de las rapaces diurnas en el Parque Estatal Cañón de Fernández en Durango, México. Detectamos 11 especies, cinco de éstas están bajo alguna categoría de riesgo según la Norma Oficial Mexicana 059-2010: gavilán pecho canela (Accipiter striatus), gavilán de cooper (A. cooperii), aguililla negra menor (Buteogallus anthracinus), aguililla rojinegra (Parabuteo unicinctus) y aguililla pecho rojo (Buteo lineatus). Las especies más abundantes fueron Coragyps atratus, Cathartes aura y Buteo jamaicensis. El hábitat donde obtuvimos más registros fue el bosque de galería. Las rapaces del área ven amenazada su conservación por la pérdida de hábitat, cacería y electrocución.

Pollination by animals contributes to the production of nearly 87.5% of the seeds and fruits in the world. Hummingbirds are one of the main groups of pollinating birds in the Americas, and they form pollination networks with the plants they visit. Few hummingbird-plant networks have been studied in tropical dry forest, which is one of the vegetation types most affected by deforestation worldwide. In this study, we describe the characteristics of the core species of a mutualistic hummingbird-plant network in a lowland dry forest located on the Yucatan Peninsula of Mexico. The study lasted a full year, from August 2017 to June 2018. Using point counts and focal observations, we identified three species of hummingbirds that visited eight plant species. The network was highly connected and had three modules—one for each hummingbird species. The core hummingbird species was Chlorostilbon canivetii, and the key plants were Cordia dodecandra, Senna racemosa and Psittacanthus mayanus. This hummingbird-plant network is apparently driven by water availability, which determines plant phenology, which in turn, determines hummingbird activity. In the context of global extinction, the conservation of core species will be critical to maintain the interactions that support all of the species in the network.

Hummingbird vocalizations are usually displayed in two contexts. When foraging or defending territories, males and females usually display relative simple calls as territorial advertisement, while during courtship males perform individually elaborate songs to mate attraction or through singing assemblies (leks). About 15% of all described hummingbird species form leks or singing assemblies during the breeding season. However, the vocal repertoire displayed by males in these arenas has been rarely described. Here we studied the songs of Green Violetear Colibri thalassinus in a temperate forest from central Tlaxcala, Mexico, to document structure and variation within and between singing assemblies established over 3 years. We found 41 well differentiated and structurally complex syllable types across eleven recorded singing groups of Green Violetears (≈12 syllable types per singing group). The songs of most birds were repeats of the same 3–4 syllables, but the syllables types emitted can vary. Bir...

Background: Information about the impact of frailty in patients with acute coronary syndromes (ACS) is scarce. No study has assessed the prognostic impact of frailty as measured by the FRAIL scale in very elderly patients with ACS. Methods: The prospective multicenter LONGEVO-SCA registry included unselected patients with ACS aged 80 years or older. A comprehensive geriatric assessment was performed during hospitalization, including frailty assessment by the FRAIL scale. The primary endpoint was mortality at 6 months. Results: A total of 532 patients were included. Mean age was 84.3 years, 61.7% male. Most patients had positive troponin levels (84%) and high GRACE risk score values (mean 165). A total of 205 patients were classified as prefrail (38.5%) and 145 as frail (27.3%). Frail and prefrail patients had a higher prevalence of comorbidities, lower left ventricle ejection fraction, and higher mean GRACE score value. A total of 63 patients (11.8%) were dead at 6 months. Both prefrailty and frailty were associated with higher 6-month mortality rates (P < .001). After adjusting for potential confounders, this association remained significant (hazard ratio [HR] 2.71; 95% confidence interval [CI] 1.09–6.73 for prefrailty and HR 2.99; 95% CI 1.20–7.44 for frailty, P = .024). The other independent predictors of mortality were age, Charlson Index, and GRACE risk score. Conclusions: The FRAIL scale is a simple tool that independently predicts mortality in unselected very elderly patients with ACS. The presence of prefrailty criteria also should be taken into account when performing risk stratification of these patients. Sin financiación 4.899 JCR (2018) Q1, 6/53 Geriatrics & Gerontology 2.123 SJR (2018) Q1, 2/152 Nursing (miscellaneous), 6/114 Geriatrics and Gerontology, 9/259 Health Policy, 139/2844 Medicine (miscellaneous) No data IDR 2018 UEM

Spatial and temporal variation in interactions between hummingbirds and plants have often been examined, and hummingbirds and insects are known to indirectly interact in networks of nectar plants. In a highland temperate forest in Hidalgo, Mexico some oak trees were heavily infested by honeydew-producing insects (family Margarodidae, tribe Xylococcini, genus Strigmacoccus) and the honeydew was consumed by hummingbirds. Here using survival analysis we investigate how the honeydew produced by dense populations of these margarodids is temporally and spatially partitioned by hummingbirds. We also measured the availability and quality of honeydew exudates, and then we recorded the time until a bird visited and used such resources. Four hummingbird species consumed this resource (Atthis eloisa, Hylocharis leucotis, Colibri thalassinus and Eugenes fulgens). Data from 294 hours of observation on seven focal trees suggested temporal and spatial segregation among visiting birds according to body size and territorial behavior during the most honeydew-limited time. Hummingbird species differed in the daily times they foraged, as well as in the location where honeydew-producing insects were visited on the trees. Temporal and spatial segregation among hummingbird species is interpreted as an adaptation to reduce the risk of aggressive encounters. This may facilitate multispecies coexistence and allow these birds to exploit honeydew more effectively.

Spatial and temporal variation in interactions between hummingbirds and plants have often been examined, and hummingbirds and insects are known to indirectly interact in networks of nectar plants. In a highland temperate forest in Hidalgo, Mexico some oak trees were heavily infested by honeydew-producing insects (family Margarodidae, tribe Xylococcini, genus Strigmacoccus) and the honeydew was consumed by hummingbirds. Here using survival analysis we investigate how the honeydew produced by dense populations of these margarodids is temporally and spatially partitioned by hummingbirds. We also measured the availability and quality of honeydew exudates, and then we recorded the time until a bird visited and used such resources. Four hummingbird species consumed this resource (Atthis eloisa, Hylocharis leucotis, Colibri thalassinus and Eugenes fulgens). Data from 294 hours of observation on seven focal trees suggested temporal and spatial segregation among visiting birds according to body size and territorial behavior during the most honeydew-limited time. Hummingbird species differed in the daily times they foraged, as well as in the location where honeydew-producing insects were visited on the trees. Temporal and spatial segregation among hummingbird species is interpreted as an adaptation to reduce the risk of aggressive encounters. This may facilitate multispecies coexistence and allow these birds to exploit honeydew more effectively [Current Zoology 57 (1): 56–62, 2011].

We report an observation of a female Lucifer Hummingbird (Calothorax lucifer) with iridescent feathers on the chin, resembling the plumage of the juvenile male. The female and nest were found in a xeric shrubland in Barranca de MetztitlBiosphere Reserve, Hidalgo State, Mexico. This is the first definitive report of a breeding female with such plumage, supporting a previous observation in which sex was not confirmed by behavior. Although this condition appears be rare in female Lucifer Hummingbirds, females in other species of hummingbirds exhibit much variation in the amount of iridescent plumage on the chin and in some, such as Costa's Hummingbirds (Calypte costae), females commonly exhibit colored feathers on the chin. SINOPSIS. Hembra adulta de Calothorax lucifer con plumas iridiscentes en la barbilla Reportamos una observacion de una hembra de colibrLucifer (Calothorax lucifer) con plumas iridiscentes en el babero, parecidas al plumaje de un macho juvenil. La hembra, la cual estaba incubando, fue encontrada en un ´ arbustiva xerofen la Reserva BiosfBarranca de Metztitlan, en Hidalgo, MEste es el primer informe definitivo de una hembra reproductora con este tipo de plumaje, en apoyo a una observaci´ on previa en donde el sexo no fue confirmado. Esta condici´ on parece ser rara en estas aves en contraste con otras especies de zumbadores como Calypte costae, pero comen otras especies dim´ orficas de M´

Las interacciones mutualistas han moldeado la biodiversidad en la tierra. A pesar de ello, hasta recientemente era dificil encontrar patrones en la estructura de este tipo de interacciones en las comunidades. En anos recientes se ha promovido el analisis de las interacciones mutualistas como redes que muestran las conexiones entre las especies. Esta aproximacion permite la descripcion de patrones estructurales que operan en las interacciones ecologicas en el nivel de comunidad y constituye un nuevo campo en la ecologia. En este estudio definimos, caracterizamos y analizamos 4 subredes de polinizacion, formadas por las interacciones entre colibries y plantas en varios paisajes del centro-este de Mexico. Las interacciones en las comunidades analizadas muestran un patron anidado en su estructura, similar al reportado para otras redes de mutualismos. Se ha sugerido que esta caracteristica, en conjunto con otras que se han descrito para este tipo de redes, promueve la coexistencia de las especies en una comunidad, teniendo por lo tanto implicaciones ecologicas y conservacionistas para las comunidades de colibries y plantas del centro-este de Mexico.

Management and conservation of natural protected areas depends critically on their biological knowledge. Herein we report a check-list of the Barranca de Metztitlan Biosphere Reserve, Hidalgo, Mexico. We registered 271 species. The families that include more species were Tyrannidae and Parulidae (24 species each one), Emberizidae (19), Icteridae (13) and Trochilidae (12). We recorded 117 resident species, 88 migratory, 34 transient, 6 with resident- migratory populations and 26 with status not clear. We registered 16 abundant species, 67 common, 153 rare, and 35 with undetermined abundance. The richest vegetation types were: submontane shrubland with 113 species, tropical deciduous forest with 97, Juniperus forest with 96, and crasicaule shrubland with Stenocereus dumortieri dominance with 91. The best represented gremials were: insectivorous (235 species), frugivorous (88), and granivorous (85). We found 17 species under some risk category according with the Mexican law, and 32 species possesses some endemic degree. In the reserve inhabit near of the 60% of the birds of the Hidalgo state and 27% of the Mexican birds. This region should be considered as an Important Bird Area in Mexico.