Euglossine bees are important pollinators of lowland Neotropical forests. Compared to disturbed h... more Euglossine bees are important pollinators of lowland Neotropical forests. Compared to disturbed habitats, undisturbed ones have been previously characterized by higher abundance and diversity of euglossine bees. Most past studies have relied on chemically baiting male bees at single sites within habitats. Over a two-year period, we employed a repeated-measures design in which we sampled bees at multiple sites within three different habitat types, reflecting a mosaic of human disturbance (farm, secondary forest, and old logged forest). After 22 monthly samples, a total of 2008 male bees were captured, representing 31 species in five genera: 1156 at the farm (57.6%, 21 spp.), 505 in the secondary forest (25.1%, 27 spp.), and 347 in the old logged forest (17.2%, 21 spp.). Eighty-one percent of the bees captured belonged to the five most abundant species: Eulaema cingulata, El. chocoana, Euglossa hansoni, Eg. ignita, and Eg. imperialis. These species differed significantly in capture frequencies among habitats. Eulaema cingulata, El. chocoana, and Eg. ignita were captured most frequently at the farm, while Eg. imperialis was most abundant in the secondary forest. In contrast, Eg. hansoni, the sole short-tongued species among the five, was equally abundant in the two forest habitats but occurred rarely on the farm. Additionally, habitats differed in bee composition. The high capture rates for long-proboscis species at the farm may have been due to their ability to extract nectar from flowers with long floral tubes, which probably occurred at a greater density on the farmed land than in the adjacent forests.Las abejas euglosinas son polinizadores importantes en bosques neotropicales de tierras bajas. Normalmente, los hábitats poco perturbados se caracterizan por presentar una mayor abundancia de abejas euglosinas que los menos intervenidos, aunque dichos resultados se basan en muestreos que usan atrayentes químicos para machos en sitios únicos por hábitat. En este estudio realizamos muestreos basados en sitios múltiples en tres hábitats adyacentes (finca, bosque secundario, y bosque maduro) a lo largo de dos años. Encontramos una mayor abundancia y diversidad de machos euglosinos en los hábitats con mayor perturbación humana que en el bosque maduro. Después de 22 muestreos mensuales captu-ramos un total de 2008 abejas representando 31 especies en cinco géneros: 1156 en la finca (57.6%, 21 spp), 505 en el bosque secundario (25.1%, 27 spp), y 347 en el bosque maduro (17.2%, 21 spp). El 80.8 por ciento de las abejas capturadas pertenecían a las cinco especies más abundantes: Eulaema cingulata, El. chocoana, Euglossa hansoni, Eg. ignita, y Eg. imperialis. Para estas especies encontramos diferencias en la frecuencia de captura entre hábitats. Eulaema cingutata, El. chocoana, y Eg. ignita fueron más frecuentes en la finca, mientras que Eg. hansoni, la única de las cinco con lengua corta, lo fue en los dos hábitats boscosos y Eg. imperialis en el bosque secundario. Adicionalmente, los hábitats difirieron en composición de abejas. Lo resultados pueden deberse a que en la finca había una mayor oferta de néctar con acceso restringido que en los busques adyacentes. El néctar, por estar en flores de corolas profundas, solo podía ser accedido por abejas de lenguas largas lo cual favorecía una mayor abundancia de euglosinas grandes con lenguas largas en la finca que en los bosques adyacentes.
Males and females of Euglossa cordata collected inside flowers of Thevetia peruviana in urban are... more Males and females of Euglossa cordata collected inside flowers of Thevetia peruviana in urban areas of eleven cities of the state of São Paulo were analysed using allozymes and nine microsatellite loci. The analyses revealed that these populations have a high genetic diversity and are under genetic equilibrium, showing low population structuring and rare diploid males; consequently, high gene flow and effective population size (Ne) are inferred. These findings corroborate previous biological observations and phylogeographic evidence that report dispersion over long distances of Euglossini species in South America.
Physica Status Solidi B-basic Solid State Physics, 2000
ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Depositi... more ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Deposition (CBD) method, varying the solution's pH between 9 and 11. The samples were characterized through transmittance and AFM measurements. It was found that the transmittance and the morphological properties as well as the growth rate of the CdS thin films are significantly affected by the solutions' pH. Good results were obtained using pH values between 9 and 10.
Euglossine bees have been described as long-distance pollinators because of their great flight ca... more Euglossine bees have been described as long-distance pollinators because of their great flight capacities although flight capacity is not necessarily correlated to home range. Here we report the nectar-foraging behavior of two euglossine species (Euglossa cordata and Eulaema nigrita) in urban areas and the predictive power of wing wear as an age estimator of these bees, using mark-recapture techniques at Thevetia peruviana trees. A total of 870 bees were marked. Recapture rates were 33% (± 19.2) for E. cordata and 25% (± 2.5) for E. nigrita. Only 7 bees were sighted at a different site from where they were first captured. More than 75% of the individuals showed site-constancy at trees for at least 30 days. Wing wear accumulation rate was variable among individuals and it was a poor predictor of age for E. cordata. Our data show that euglossine bees may have small foraging ranges in urban areas, indicating that home ranges greatly differ from their flight capacity and homing ability. Euglossine Bienen (Prachtbienen) werden im allgemeinen als Weitdistanzbestäuber eingestuft, die grosse Sammelgebiete abdecken können. Sie sind dazu in der Lage aufgrund ihrer grossen Flugkapazität und dies obwohl Flugkapazität nicht notwendigerweise mit dem Heimatradius korreliert sein muss. In dieser Arbeit untersuchten wir das Nektarsammelverhalten von zwei Prachtbienenarten in Stadtgebieten, und wir bewerteten die Aussagekraft des Flügelabnutzungsgrads für die Altersabschätzung. Wir beschreiben zudem eine effiziente Methode zur Markierung dieser Bienen, die Etiketten leicht durch ihr intensives Putzverhalten verlieren können. Weibchen und Männchen von Euglossa cordata (nw = 596; nm = 53) und von Eulaema nigrita (nw = 106; nm = 115) (Tab. I) wurden markiert und später auf blühenden Bäumen der Art Thevetia peruviana (Apocynaceae) in einem Umkreis von 0,24–5,45 km im Stadtgebiet von São Carlos (SP, Brasilien) wiedergefangen. Die mittlere Wiederfangrate für Eg. cordata lag bei 33 % (± 19,2) und die für El. nigrita bei 25 % (± 2,5). Von den 213 wiedergefangenen Bienen wurden jedoch nur sieben an einem anderen Ort wiedergefangen als dem, an dem sie zuerst gefangen und markiert worden waren (Tab. II). Über 75 % der Bienen beider Arten zeigten ausserdem eine Ortskonstanz im Sammelverhalten an den Bäumen über mindestens 30 Tage hinweg. Bei Männchen war der Zeitraum allerdings kürzer als bei Weibchen (Abb. 3 und 4). Diese Ergebnisse weisen daraufhin, dass Prachtbienen bevorzugt über kurze Distanzen hinweg Nektar sammeln, dass sie ihre Sammelterritorien jedoch nach einiger Zeit wechseln können. Der Flügelabnutzungsgrad erwies sich als individuell stark variabel und schien bei Eg. cordata kein guter Altersindikator zu sein (Abb. 5). Unsere Daten zeigen, dass Euglossinen in Stadtgebieten aufgrund der Verteilung von Blüten relativ kleine Sammelgebiete haben können. Dies bedeutet, dass sich Heimatradien stark von den Faktoren Flugkapazität und Heimfindungsvermögen unterscheiden können.
Physica Status Solidi B-basic Solid State Physics, 2000
ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Depositi... more ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Deposition (CBD) method, varying the solution's pH between 9 and 11. The samples were characterized through transmittance and AFM measurements. It was found that the transmittance and the morphological properties as well as the growth rate of the CdS thin films are significantly affected by the solutions' pH. Good results were obtained using pH values between 9 and 10.
One of the steps to improve the efficiency of thin film solar cells is the exhaustive comprehensi... more One of the steps to improve the efficiency of thin film solar cells is the exhaustive comprehension of the physical aspects present in the bulk of materials and their interphases. TEM is a tool that provides significant information about the specimen, by means of e.g. analysis of crystalline structure, defects visualization, grain boundaries and interfaces, and composition mapping. Additionally, Electron Holography allows measuring the inner potentials and electric fields [1], which will be decisive for the performance of thin films solar cells.
Euglossine bees are important pollinators of lowland Neotropical forests. Compared to disturbed h... more Euglossine bees are important pollinators of lowland Neotropical forests. Compared to disturbed habitats, undisturbed ones have been previously characterized by higher abundance and diversity of euglossine bees. Most past studies have relied on chemically baiting male bees at single sites within habitats. Over a two-year period, we employed a repeated-measures design in which we sampled bees at multiple sites within three different habitat types, reflecting a mosaic of human disturbance (farm, secondary forest, and old logged forest). After 22 monthly samples, a total of 2008 male bees were captured, representing 31 species in five genera: 1156 at the farm (57.6%, 21 spp.), 505 in the secondary forest (25.1%, 27 spp.), and 347 in the old logged forest (17.2%, 21 spp.). Eighty-one percent of the bees captured belonged to the five most abundant species: Eulaema cingulata, El. chocoana, Euglossa hansoni, Eg. ignita, and Eg. imperialis. These species differed significantly in capture frequencies among habitats. Eulaema cingulata, El. chocoana, and Eg. ignita were captured most frequently at the farm, while Eg. imperialis was most abundant in the secondary forest. In contrast, Eg. hansoni, the sole short-tongued species among the five, was equally abundant in the two forest habitats but occurred rarely on the farm. Additionally, habitats differed in bee composition. The high capture rates for long-proboscis species at the farm may have been due to their ability to extract nectar from flowers with long floral tubes, which probably occurred at a greater density on the farmed land than in the adjacent forests.Las abejas euglosinas son polinizadores importantes en bosques neotropicales de tierras bajas. Normalmente, los hábitats poco perturbados se caracterizan por presentar una mayor abundancia de abejas euglosinas que los menos intervenidos, aunque dichos resultados se basan en muestreos que usan atrayentes químicos para machos en sitios únicos por hábitat. En este estudio realizamos muestreos basados en sitios múltiples en tres hábitats adyacentes (finca, bosque secundario, y bosque maduro) a lo largo de dos años. Encontramos una mayor abundancia y diversidad de machos euglosinos en los hábitats con mayor perturbación humana que en el bosque maduro. Después de 22 muestreos mensuales captu-ramos un total de 2008 abejas representando 31 especies en cinco géneros: 1156 en la finca (57.6%, 21 spp), 505 en el bosque secundario (25.1%, 27 spp), y 347 en el bosque maduro (17.2%, 21 spp). El 80.8 por ciento de las abejas capturadas pertenecían a las cinco especies más abundantes: Eulaema cingulata, El. chocoana, Euglossa hansoni, Eg. ignita, y Eg. imperialis. Para estas especies encontramos diferencias en la frecuencia de captura entre hábitats. Eulaema cingutata, El. chocoana, y Eg. ignita fueron más frecuentes en la finca, mientras que Eg. hansoni, la única de las cinco con lengua corta, lo fue en los dos hábitats boscosos y Eg. imperialis en el bosque secundario. Adicionalmente, los hábitats difirieron en composición de abejas. Lo resultados pueden deberse a que en la finca había una mayor oferta de néctar con acceso restringido que en los busques adyacentes. El néctar, por estar en flores de corolas profundas, solo podía ser accedido por abejas de lenguas largas lo cual favorecía una mayor abundancia de euglosinas grandes con lenguas largas en la finca que en los bosques adyacentes.
Males and females of Euglossa cordata collected inside flowers of Thevetia peruviana in urban are... more Males and females of Euglossa cordata collected inside flowers of Thevetia peruviana in urban areas of eleven cities of the state of São Paulo were analysed using allozymes and nine microsatellite loci. The analyses revealed that these populations have a high genetic diversity and are under genetic equilibrium, showing low population structuring and rare diploid males; consequently, high gene flow and effective population size (Ne) are inferred. These findings corroborate previous biological observations and phylogeographic evidence that report dispersion over long distances of Euglossini species in South America.
Physica Status Solidi B-basic Solid State Physics, 2000
ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Depositi... more ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Deposition (CBD) method, varying the solution's pH between 9 and 11. The samples were characterized through transmittance and AFM measurements. It was found that the transmittance and the morphological properties as well as the growth rate of the CdS thin films are significantly affected by the solutions' pH. Good results were obtained using pH values between 9 and 10.
Euglossine bees have been described as long-distance pollinators because of their great flight ca... more Euglossine bees have been described as long-distance pollinators because of their great flight capacities although flight capacity is not necessarily correlated to home range. Here we report the nectar-foraging behavior of two euglossine species (Euglossa cordata and Eulaema nigrita) in urban areas and the predictive power of wing wear as an age estimator of these bees, using mark-recapture techniques at Thevetia peruviana trees. A total of 870 bees were marked. Recapture rates were 33% (± 19.2) for E. cordata and 25% (± 2.5) for E. nigrita. Only 7 bees were sighted at a different site from where they were first captured. More than 75% of the individuals showed site-constancy at trees for at least 30 days. Wing wear accumulation rate was variable among individuals and it was a poor predictor of age for E. cordata. Our data show that euglossine bees may have small foraging ranges in urban areas, indicating that home ranges greatly differ from their flight capacity and homing ability. Euglossine Bienen (Prachtbienen) werden im allgemeinen als Weitdistanzbestäuber eingestuft, die grosse Sammelgebiete abdecken können. Sie sind dazu in der Lage aufgrund ihrer grossen Flugkapazität und dies obwohl Flugkapazität nicht notwendigerweise mit dem Heimatradius korreliert sein muss. In dieser Arbeit untersuchten wir das Nektarsammelverhalten von zwei Prachtbienenarten in Stadtgebieten, und wir bewerteten die Aussagekraft des Flügelabnutzungsgrads für die Altersabschätzung. Wir beschreiben zudem eine effiziente Methode zur Markierung dieser Bienen, die Etiketten leicht durch ihr intensives Putzverhalten verlieren können. Weibchen und Männchen von Euglossa cordata (nw = 596; nm = 53) und von Eulaema nigrita (nw = 106; nm = 115) (Tab. I) wurden markiert und später auf blühenden Bäumen der Art Thevetia peruviana (Apocynaceae) in einem Umkreis von 0,24–5,45 km im Stadtgebiet von São Carlos (SP, Brasilien) wiedergefangen. Die mittlere Wiederfangrate für Eg. cordata lag bei 33 % (± 19,2) und die für El. nigrita bei 25 % (± 2,5). Von den 213 wiedergefangenen Bienen wurden jedoch nur sieben an einem anderen Ort wiedergefangen als dem, an dem sie zuerst gefangen und markiert worden waren (Tab. II). Über 75 % der Bienen beider Arten zeigten ausserdem eine Ortskonstanz im Sammelverhalten an den Bäumen über mindestens 30 Tage hinweg. Bei Männchen war der Zeitraum allerdings kürzer als bei Weibchen (Abb. 3 und 4). Diese Ergebnisse weisen daraufhin, dass Prachtbienen bevorzugt über kurze Distanzen hinweg Nektar sammeln, dass sie ihre Sammelterritorien jedoch nach einiger Zeit wechseln können. Der Flügelabnutzungsgrad erwies sich als individuell stark variabel und schien bei Eg. cordata kein guter Altersindikator zu sein (Abb. 5). Unsere Daten zeigen, dass Euglossinen in Stadtgebieten aufgrund der Verteilung von Blüten relativ kleine Sammelgebiete haben können. Dies bedeutet, dass sich Heimatradien stark von den Faktoren Flugkapazität und Heimfindungsvermögen unterscheiden können.
Physica Status Solidi B-basic Solid State Physics, 2000
ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Depositi... more ABSTRACT CdS thin films were deposited on ZnO and SnO2:F substrates by the Chemical Bath Deposition (CBD) method, varying the solution's pH between 9 and 11. The samples were characterized through transmittance and AFM measurements. It was found that the transmittance and the morphological properties as well as the growth rate of the CdS thin films are significantly affected by the solutions' pH. Good results were obtained using pH values between 9 and 10.
One of the steps to improve the efficiency of thin film solar cells is the exhaustive comprehensi... more One of the steps to improve the efficiency of thin film solar cells is the exhaustive comprehension of the physical aspects present in the bulk of materials and their interphases. TEM is a tool that provides significant information about the specimen, by means of e.g. analysis of crystalline structure, defects visualization, grain boundaries and interfaces, and composition mapping. Additionally, Electron Holography allows measuring the inner potentials and electric fields [1], which will be decisive for the performance of thin films solar cells.
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