PROYECTO CONVOCATORIA CIENCIA BÁSICA CONACYT 2014

Clave 237532: Cambio Climático y polinizadores: efecto del incremento térmico sobre la estabilidad del desarrollo e indicadores de aptitud biológica en abejas tropicales de México (Hymenoptera: Apidae)

RESPONSABLE TECNICO
DR JOSE JAVIER QUEZADA EUAN
Colaboradores:
Dr Luis Medina Medina
Dr William May Itza
M en C Humberto Moo Valle
Professor Robert J Paxton

RESUMEN

Las abejas (Hymenoptera: Apoidea: Anthophila) son los principales polinizadores de los ecosistemas. Sin embargo, existen pocos estudios sobre el efecto del cambio en el régimen de temperaturas global sobre la sobrevivencia y distribución de abejas mismos que se han centrado principalmente en la abeja melífera  (Apis mellifera) y sus ecotipos Europeos y de clima templado. No obstante, la abeja melífera representa un caso especial de las casi 20,000 especies de abejas a nivel mundial ya que presenta homotermia activa. En contraste, la mayoría de las especies eusociales, incluidas las abejas sin aguijón de distribución exclusivamente tropical, funcionan como organismos hectotermos. En México, en las regiones tropicales predomina la abeja A. mellifera africanizada, pero no existe información de la tolerancia de ecotipos tropicales de esta especie a estrés térmico. Por otra parte, Meliponini es un grupo ampliamente diverso en los trópicos y subtrópicos de nuestro país, constituyendo los polinizadores más importantes de estos ecosistemas. La apicultura y meliponicultura en México son actividades con fuerte tradición que representan importantes ingresos económicos para el país y para un gran número de familias campesinas además de tener un valor cultural para las etnias indígenas por lo que su conservación debe ser parte de las prioridades del rescate de polinizadores.  En este proyecto se propone evaluar la tolerancia de estos importantes insectos a las variaciones térmicas, el efecto sobre la estabilidad del desarrollo, cambios en la conducta y la capacidad reproductiva de individuos producidos bajo regímenes de incremento térmico mismos que pueden afectar la capacidad de sobreviencia y viabilidad de las especies y de los ecosistemas que de ellas dependen.

Quezada-Euán JJG; May-Itzá W de J; Montejo E; Moo-Valle H (2015) Isometric worker size variation in relation to individual foraging preference and seasonal colony growth in stingless bees. Insectes Sociaux 62: 73-80.

Abstract

Isometric worker size variation has been found in various species of stingless bees but the adaptive value of this phenomenon is little understood. We studied intra-colony worker size variation in Melipona in relation to individual foraging preference and colony growth in periods of resource abundance and scarcity. We found significant forager size differences across colonies. In spite of this, intra-colony size of foragers collecting different resources was highly similar, suggesting that foraging preferences and flexibility are size constrained. On the other hand, inter-colony forager size was associated with parameters of colony growth, albeit differently, depending on the season. Our results suggest that isometric forager size may reflect the state of food storage, and thus, colony development in stingless bees. It seems that stingless bee communities respond to seasonal abundance and scarcity with variable cycles of individual colony growth and reduction of reserves that may explain the asynchronous reproduction of colonies, spanning years in these insects.

PDF Insectes Sociaux

Claudio Soto Vargas

Tesis de Maestría: Efectos de la inoculación de esporas de Nosema ceranae (Microsporidia) y detección del virus de alas deformes (DWV) en la abeja nativa sin aguijón Melipona beecheii (Hymenoptera: Meliponini) en Yucatán , México.

2014

Asesores: Dr Luis Medina Medina, Dr William May Itzá

Pokorny T., Loose D., Dyker G., Quezada-Euán J.J.G., Eltz T. (2015) Dispersal ability of male orchid bees and direct evidence for long-range flights. Apidologie 46: 224-237. DOI 10.1007/s13592-014-0317-y

 

Abstract

Male Neotropical orchid bees collect volatile chemicals from various sources in the environment in order to compose their characteristic perfume bouquets. Amongst other plants, over 600 species of orchids are exclusively pollinated by the bees during their quest for volatiles. Since the plants usually have a scattered distribution, it is assumed that orchid bees can transport the pollinaria across several kilometres due to their flight capabilities and a high dispersal potential. Until now, very long-range flight distances (up to 45 km) of male orchid bees have only been indirectly inferred from habitat requirements of orchids whose pollinaria were carried by captured males, whereas the distances established by direct measures (mark and recapture, radio telemetry) only span distances of up to around 6 km. The discrepancy between inferred and proven distances led us to readdress the question of dispersal ability of male orchid bees. In this study, we used tag, scratch and chemical marking of large numbers of bees to clarify two aspects: (1) the effect of moderate natural obstacles on dispersal and (2) the possibility of very long-range movements across a terrain lacking such obstacles. Our results suggest that a moderate natural obstacle (a valley separating opposite ridges) does not restrain orchid bee movements. Individual bees achieved extraordinary flight distances of more than 50 km across even terrain, extending the directly proven flight distances of male bees by more than an order of magnitude.

 

 

 

 

  

PDF Apidologie

Afik O., Delaplane K. S., Shafir S.,  Moo-Valle H., Quezada-Euán J. J. G. (2014) Nectar minerals as regulators of flower visitation in stingless bees and nectar hoarding wasps. J. Chem. Ecol. 40:476–483.  DOI 10.1007/s10886-014-0455-8.

 

Abstract

Various nectar components have a repellent effect on flower visitors, and their adaptive advantages for the plant are not well understood. Persea americana (avocado) is an example of a plant that secretes nectar with repellent components. It was demonstrated that the mineral constituents of this nectar, mainly potassium and phosphate, are concentrated enough to repel honey bees, Apis mellifera, a pollinator often used for commercial avocado pollination. Honey bees, however, are not the natural pollinator of P. americana, a plant native to Central America. In order to understand the role of nectar minerals in plant—pollinator relationships, it is important to focus on the plant’s interactions with its natural pollinators. Two species of stingless bees and one species of social wasp, all native to the Yucatan Peninsula, Mexico, part of the natural range of P. americana, were tested for their sensitivity to sugar solutions enriched with potassium and phosphate, and compared with the sensitivity of honey bees. In choice tests between control and mineral-enriched solutions, all three native species were indifferent for mineral concentrations lower than those naturally occurring in P. americana nectar. Repellence was expressed at concentrations near or exceeding natural concentrations. The threshold point at which native pollinators showed repellence to increasing levels of minerals was higher than that detected for honey bees. The results do not support the hypothesis that high mineral content is attractive for native Hymenopteran pollinators; nevertheless, nectar mineral composition may still have a role in regulating flower visitors through different levels of repellency

  

 

 

PDF J. Chem. Ecol.

May-Itzá W. de J., Medina Medina L. A., Medina S., Paxton R. J., Quezada-Euán J. J. G. (2014) Seasonal nest characteristics of a facultatively social orchid bee, Euglossa viridissima, in the Yucatan Peninsula, Mexico. Insect. Soc. 61: 183-190.

Abstract

Euglossines have long been regarded as largely solitary, though some species are known to exhibit social behavior. We studied the nesting behavior of Euglossa viridissima over an annual cycle, comparing sociality and offspring production across the rainy (RS) and dry seasons (DS) in the Yucatan Peninsula of Mexico. Nests were built in both the RS and the DS, but with greater nest initiation and brood provisioning in the RS, presumably as a consequence of more floral resources at this time of year. Across the year, numerical sex ratios were female biased (0.7 as females/total); sex ratios varied across individual nests from 0.3 to 1.00, though without a clear relationship to sociality. Egg-to-adult development was quicker in females than males and, within a sex, quicker when ambient temperatures were higher. Multi-female (social) nests were only founded at the end of the RS and the beginning of the DS, coincided with the presence of Hymenopteran and Dipteran parasites in nests headed by solitary females. Reduced floral resources and a higher risk of parasitism, possibly coupled with higher female density or reduced nesting sites, may be factors favoring the formation of multi-female associations in this euglossine. Better nourishment of foundress females in the RS may improve lifespan and permit overlapping generations which, coupled with the kin structure of their nests, may favor social nesting in E. viridissima.

PDF Insect. Soc.

Pokorny T., Lunau K., Quezada-Euan J. J. G.,  Eltz T. (2014) Cuticular hydrocarbons distinguish cryptic sibling species in Euglossa orchid bees. Apidologie 45: 276-283.

 

Abstract

Cuticular lipid profiles have been shown to be species specific within many insect genera, allowing a chemotaxonomic classification of individuals. In this study, we analysed the cuticular lipids of the orchid bees Euglossa viridissima Friese and Euglossa dilemma Bembé & Eltz, cryptic sibling species whose taxonomic status has only recently been clarified. Male individuals of both species were obtained from two locations on the Yucatán Peninsula, Mexico, both in the dry and wet seasons. Their hydrocarbon profiles proved to be species specific, irrespective of location and season. They also allowed a correct assignment of a rare morph of E. viridissima which had long obscured the distinction of the two species. Our results suggest that cuticular hydrocarbon profiles may be suited for chemical taxonomy of orchid bees and might provide an additional clue for difficult species distinctions.

PDF Apidologie 

Ruiz C., May-Itza W. de J., Quezada-Euán J. J. G., De la Rúa P. (2013) Presence of nuclear copies of mitochondrial origin (NUMTs) in two related species of stingless bee genus Melipona (Hymenoptera: Meliponini). J. Zool. Syst. Evol. Res. 51: 107-113. DOI: 10.1111/jsz.12011 ISSN: 0947-5745

Abstract

Transferred copies of mitochondrial DNA (mtDNA) into the nuclear genome (numts) have been reported in several Hymenoptera species, even at a high density in the honey bee nuclear genome. The accidental amplification of numts in phylogenetic studies focused on mtDNA highlights the importance of a correct determination of numts and their related mtDNA sequences. We report here the presence of numts derived from a mitochondrial rDNA 16S gene in the genome of the stingless bee species Melipona colimana and M. fasciata (tribe Meliponini) from Western Mexico. PCR products were cloned in both species obtaining thirty paralogous numts. Numts were identified by the presence of insertions and deletions and the disruption of the 16S secondary structure. Further phylogenetic analyses including alternative mitochondrial cox1 and nuclear ITS1 genes have revealed the presence of another numt (cox1) in the nuclear genome of these two species, and place both as sister lineages within the subgenus Michmelia. This is one of the first studies reporting the presence of numts in Meliponini species, and supports previous studies suggesting frequent transfer of mtDNA to the nuclear genome in Hymenoptera.

 PDF J. Zool. Syst. Evol. Res.

 Quezada-Euán J J G, Ramírez J, Eltz T, Pokorny T, Medina R, Monsreal R (2013) Does sensory deception matter in eusocial obligate food robber systems? A study of Lestrimelitta and stingless bee hosts. Animal Behaviour 85: 817-823 ISSN:0003-3472. http://dx.doi.org/10.101/j.anbehav.2013.01.028

Abstract

 Social parasites can break into their host colonies using sensory deception, force, or both. To evaluate the role of sensory deception in eusocial obligate food robbers, we studied the Mesoamerican stingless bee Lestrimelitta niitkib–host species system, including preferred and nonpreferred host species. The use of citral as a propaganda substance is documented in L. niitkib, but possible mechanisms used by individual scouts to overcome host species recognition have not been studied. We analysed the cuticular profiles of L. niitkib and host species, coupled with bioassays of time to aggression (latency) and included data on host species raid frequency. We found that L. niitkib has a simple, but not insignificant, cuticular profile. Generally, L. niitkib cuticular profiles were similar to (but did not mimic) profiles of its preferred host species and differed from profiles of nonpreferred hosts. As expected, latency generally fitted a recognition system based on the degree of similarity between the cleptobiont's cuticular label and the host species template, with chemically similar species reacting slower and chemically distant species reacting rapidly to L. niitkib. There was a positive correlation between raid ratio and latency, indicating that the speed of detection and aggression towards L. niitkib scouts could influence host species selection. Cuticular profile similarity of individual L. niitkib scouts to host species may help L. niitkib scouts evade recognition and attacks from guards. In a further step, unnoticed L. niitkib scouts could successfully recruit nestmates to mass-raid host species colonies. The fact that L. niitkib can also plunder aggressive species, suggests that obligate cleptobiosis within its narrow biological niche could be characterized by flexibility in invasion strategies to allow exploiting a broad range of host species and be successful over evolutionary times.

PDF Animal Behaviour