Natural History, Learning, And Social Behavior in Solitary Sweat Bees (Hymenoptera, Halictidae)

The University of Kansas has long historical connections with Central America and the many Central Americans who have earned graduate degrees at KU. This work is part of the Central American Theses and Dissertations collection in KU ScholarWorks and is being made freely available with permission of the author through the efforts of Professor Emeritus Charles Stansifer of the History department and the staff of the Scholarly Communications program at the University of Kansas Libraries’ Center for Digital Scholarship.The natural history of two Costa Rican species of sweat bees was studied to better understand the advantages and disadvantages associated with group-living and cooperative behavior in bees. One of the bees was a new species, and was described and named after Jose Figueres Ferrar, a famous Costa Rican patriot. Studies of the behavior of these bees, in turn, are used as general models for studying social behavior. Experimental studies on one of the species (Lasioglossum figueresi) showed that females recognize their homes (nests) in part by means of individual "chemical signatures" deposited at the entrance-way. The use of chemical signatures by solitary bees to recognize their nests is useful because the same perceptual systems can be used by the bees to recognize other bees, and so form stable social groups. Experiments on mate recognition by male bees also showed that males can recognize individual females by their odors. Details of the courtship behavior of a solitary bee (Nomia triangulifera) show it to have the most complex courtship behavior known to date in bees. Together these studies show the importance of behavior as both products, and producers, of evolution

Reference Transcriptome for a Facultatively Eusocial Bee, Megalopta genalis

This article analyses gendering processes in two distinct models of work organization. It is a widespread belief that, compared to hierarchical (Tayloristic) organizations, team-based work offers opportunities for a high quality of working life to a broader range of employees, both men and women. Our research, however, suggests that gender inequality is (re)produced in both settings and results from the so-called gender subtext. The gender subtext is the set of often concealed power-based processes (re)producing gender distinction in social practices through organizational and individual arrangements. We draw a comparison between the gender subtext of Tayloristic and team-based work organizations through a theoretical analysis, illustrated by empirical data concerning the functioning of the gender subtext in organizations in the Dutch banking sector. Taylorism and team-based work differ in their conceptualization of organization and job design, but, when it comes to the gender subtext, it is six of one and half a dozen of the other. We argue that in both approaches a gender subtext contributes to the emergence of different but gendered notions of the ‘disembodied worker’. In both cases the notion of the abstract worker is implicitly loaded with masculine connotations. This gender bias is supported by two factors influencing the gendering of jobs: the gender connotations of care responsibilities and of qualification profiles. These implicit connotations produce and reinforce unequal opportunities for men and women to get highly qualified or management jobs. Our research, therefore, questions the self-evidence of stating that team-based work will offer opportunities for a higher quality of working life for women

Fungal-Fungal Interactions in Leaf-Cutting Ant Agriculture

Many organisms participate in symbiotic relationships with other organisms, yet studies of symbioses typically have focused on the reciprocal costs and benefits within a particular host-symbiont pair. Recent studies indicate that many ecological interactions involve alliances of symbionts acting together as mutualistic consortia against other consortia. Such interacting consortia are likely to be widespread in nature, even if the interactions often occur in a cryptic fashion. Little theory and empirical data exist concerning how these complex interactions shape ecological outcomes in nature. Here, we review recent work on fungal-fungal interactions between two consortia: (i) leaf-cutting ants and their symbiotic fungi (the latter grown as a food crop by the former) and (ii) tropical plants and their foliar endophytes (the cryptic symbiotic fungi within leaves of the former). Plant characteristics (e.g., secondary compounds or leaf physical properties of leaves) are involved in leaf-cutting ant preferences, and a synthesis of published information suggests that these plant traits could be modified by fungal presence. We discuss potential mechanisms for how fungal-fungal interactions proceed in the leaf-cutting ant agriculture and suggest themes for future research

Cleaner Mites: Sanitary Mutualism In The Miniature Ecosystem Of Neotropical Bee Nests

Cleaning symbioses represent classic models of mutualism, and some bee mites are thought to perform cleaning services for their hosts in exchange for suitable environments for reproduction and dispersal. These mutual benefits, however, have not been rigorously demonstrated. We tested the sanitary role of bee mites by correlating mite loads with fungal contamination in natural nests of Megalopta genalis and Megalopta ecuadoria and by experimentally manipulating mite loads in artificial cells with developing brood. Field observations revealed significant correlations between the presence of mites and the absence of fungi inside the brood cells, as well as between the absence of mites and increased bee mortality. Likewise, experimental brood cells with mites have fewer fungal colonies than do cells without mites. Field observations and experimental manipulations, therefore, provide clear evidence of the sanitary effect of mites in nests of Megalopta bees. This bee-mite association constitutes one of the few examples of terrestrial cleaning mutualisms.Integrative Biolog

Age-Related Mushroom Body Expansion in Male Sweat Bees and Bumble Bees

A well-documented phenomenon among social insects is that brain changes occur prior to or at the onset of certain experiences, potentially serving to prime the brain for specific tasks. This insight comes almost exclusively from studies considering developmental maturation in females. As a result, it is unclear whether age-related brain plasticity is consistent across sexes, and to what extent developmental patterns differ. Using confocal microscopy and volumetric analyses, we investigated age-related brain changes coinciding with sexual maturation in the males of the facultatively eusocial sweat bee, Megalopta genalis, and the obligately eusocial bumble bee, Bombus impatiens. We compared volumetric measurements between newly eclosed and reproductively mature males kept isolated in the lab. We found expansion of the mushroom bodies—brain regions associated with learning and memory—with maturation, which were consistent across both species. This age-related plasticity may, therefore, play a functionally-relevant role in preparing male bees for mating, and suggests that developmentally-driven neural restructuring can occur in males, even in species where it is absent in females

Biological notes on a fungus-growing ant, Trachymyrmex cf. zeteki (Hymenoptera, Formicidae, Attini) attacked by a diverse community of parasitoid wasps (Hymenoptera, Diapriidae)

A number of wasps in the family Diapriidae, subfamily Diapriinae (Proctotrupoidea), are parasitoids that specialize on ant larvae. These wasps are abundant and diverse in the Neotropics, but little is known about their biology. We studied parasitism rates by an array of diapriine wasps that attack the larvae of fungus-growing ants, Trachymyrmex cf. zeteki, in a single population (near Gamboa, Panama). Relatively little is known about the biology and natural history of these ants, so we also present data on colony size and nest architecture. We excavated 136 colonies in central Panama from June to September 2006, and 20 nests from July 2009. We reared six wasp morphotypes; two of them in the genus Mimopriella Masner and Garcia, one Oxypria Kieffer, two Szelenyiopria Fabritius and one Acanthopria Ashmead. The mean intensity of larval parasitism per ant colony was 33.9% (2006), and its prevalence across all ant populations was 27.2% (2006 and 2009). Parasitism rates were not positively correlated with host colony size. A single case of super-parasitism was documented in which two Oxypria males were reared from the same host larva.Museo de La Plat