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Peter J Neumann - One of the best experts on this subject based on the ideXlab platform.
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social parasitism by honeybee workers Apis mellifera capensis esch evidence for pheromonal resistance to host queen s signals
Behavioral Ecology and Sociobiology, 2006Co-Authors: Vincent Dietemann, Jochen Pflugfelder, Stephan Hartel, Peter J Neumann, Robin M. CreweAbstract:Social parasites exploit their host’s communication system to usurp resources and reproduce. In the honeybee, Apis mellifera, worker reproduction is regulated by pheromones produced by the queen and the brood. Workers usually reproduce when the queen is removed and young brood is absent. However, Cape honeybee workers, Apis mellifera capensis, are facultative intraspecific social parasites and can take over reproduction from the host queen. Investigating the manner in which parasitic workers compete with host queens pheromonally can help us to understand how such parasitism can evolve and how reproductive division of labour is regulated. In A. m. capensis, worker reproduction is associated with the production of queen-like pheromones. Using pheromonal contest experiments, we show that Apis mellifera scutellata queens do not prevent the production of queen-like mandibular gland compounds by the parasites. Given the importance of these pheromones in acquiring reproductive status, our data suggest that the single invasive lineage of parasitic workers occurring in the range of A. m. scutellata was selected for its superior ability to produce these signals despite the presence of a queen. Such resistance was indeed less frequent amongst other potentially parasitic lineages. Resistance to reproductive regulation by host queens is probably the key factor that facilitates the evolution of social parasitism by A. m. capensis workers. It constitutes a mechanism that allows workers to evade reproductive division of labour and to follow an alternative reproductive option by acquiring direct fitness in foreign colonies instead of inclusive fitness in their natal nests.
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behavioural basis for social parasitism of cape honeybees Apis mellifera capensis
Apidologie, 2002Co-Authors: Peter J Neumann, Randall HepburnAbstract:Cape honeybee workers show important pre-adaptations for social parasitism and can cause the dwindling colony syndrome of host colonies. Parasitic workers may drift or actively dis- perse into host colonies. They may also join absconding swarms, which can merge with host colonies. After transmission, parasitic workers have to establish themselves in the host, which is probably pro- moted by their spatial distribution, their readiness to gain trophallactic dominance and their ability to survive worker-worker aggression. Established parasitic workers have to evade egg removal by other workers in host colonies. The resulting offspring is preferentially fed, can be expected to be highly virulent and may show different behaviour in the course of infestation. It is unknown why and how the host queen is lost. High numbers of parasitic workers are reared until the host colony dies or absconds. This offspring can infest new host colonies, thereby completing the social parasitic life cycle. Apis mellifera capensis / Apis mellifera scutellata / honeybee / social parasitism / worker repro- duction
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social parasitism by honeybee workers Apis mellifera capensis escholtz host finding and resistance of hybrid host colonies
Behavioral Ecology, 2001Co-Authors: Peter J Neumann, Sarah E. Radloff, Randall Hepburn, Robin F. A. Moritz, Sacha L ReeceAbstract:We studied possible host finding and resistance mechanisms of host colonies in the context of social parasitism by Cape honeybee (Apis mellifera capensis) workers. Workers often join neighboring colonies by drifting, but long-range drifting (dispersal) to colonies far away from the maternal nests also rarely occurs. We tested the impact of queenstate and taxon of mother and host colonies on drifting and dispersing of workers and on the hosting of these workers in A. m. capensis, A. m. scutellata, and their natural hybrids. Workers were paint-marked according to colony and reintroduced into their queenright or queenless mother colonies. After 10 days, 579 out of 12,034 labeled workers were recaptured in foreign colonies. We found that drifting and dispersing represent different behaviors, which were differently affected by taxon and queenstate of both mother and host colonies. Hybrid workers drifted more often than A. m. capensis and A. m. scutellata. However, A. m. capensis workers dispersed more often than A. m. scutellata and the hybrids combined, and A. m. scutellata workers also dispersed more frequently than the hybrids. Dispersers from queenright A. m. capensis colonies were more often found in queenless host colonies and vice versa, indicating active host searching and/or a queenstate-discriminating guarding mechanism. Our data show that A. m. capensis workers disperse significantly more often than other races of A. mellifera, suggesting that dispersing represents a host finding mechanism. The lack of dispersal in hybrids and different hosting mechanisms of foreign workers by hybrid colonies may also be responsible for the stability of the natural hybrid zone between A. m. capensis and A. m. scutellata. Key words: Apis mellifera capensis, Apis mellifera scutellata, honeybee, host finding, hybrids, social parasitism. [Behav Ecol 12:419–428 (2001)]
Robin M. Crewe - One of the best experts on this subject based on the ideXlab platform.
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social parasitism by honeybee workers Apis mellifera capensis esch evidence for pheromonal resistance to host queen s signals
Behavioral Ecology and Sociobiology, 2006Co-Authors: Vincent Dietemann, Jochen Pflugfelder, Stephan Hartel, Peter J Neumann, Robin M. CreweAbstract:Social parasites exploit their host’s communication system to usurp resources and reproduce. In the honeybee, Apis mellifera, worker reproduction is regulated by pheromones produced by the queen and the brood. Workers usually reproduce when the queen is removed and young brood is absent. However, Cape honeybee workers, Apis mellifera capensis, are facultative intraspecific social parasites and can take over reproduction from the host queen. Investigating the manner in which parasitic workers compete with host queens pheromonally can help us to understand how such parasitism can evolve and how reproductive division of labour is regulated. In A. m. capensis, worker reproduction is associated with the production of queen-like pheromones. Using pheromonal contest experiments, we show that Apis mellifera scutellata queens do not prevent the production of queen-like mandibular gland compounds by the parasites. Given the importance of these pheromones in acquiring reproductive status, our data suggest that the single invasive lineage of parasitic workers occurring in the range of A. m. scutellata was selected for its superior ability to produce these signals despite the presence of a queen. Such resistance was indeed less frequent amongst other potentially parasitic lineages. Resistance to reproductive regulation by host queens is probably the key factor that facilitates the evolution of social parasitism by A. m. capensis workers. It constitutes a mechanism that allows workers to evade reproductive division of labour and to follow an alternative reproductive option by acquiring direct fitness in foreign colonies instead of inclusive fitness in their natal nests.
Ingemar Fries - One of the best experts on this subject based on the ideXlab platform.
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nosema ceranae in european honey bees Apis mellifera
Journal of Invertebrate Pathology, 2010Co-Authors: Ingemar FriesAbstract:Nosema ceranae is a microsporidian parasite described from the Asian honey bee, Apis cerana. The parasite is cross-infective with the European honey bee, Apis mellifera. It is not known when or where N. ceranae first infected European bees, but N. ceranae has probably been infecting European bees for at least two decades. N. ceranae appears to be replacing Nosema Apis, at least in some populations of European honey bees. This replacement is an enigma because the spores of the new parasite are less durable than those of N. Apis. Virulence data at both the individual bee and at the colony level are conflicting possibly because the impact of this parasite differs in different environments. The recent advancements in N. ceranae genetics, with a draft assembly of the N. ceranae genome available, are discussed and the need for increased research on the impacts of this parasite on European honey bees is emphasized.
Sacha L Reece - One of the best experts on this subject based on the ideXlab platform.
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social parasitism by honeybee workers Apis mellifera capensis escholtz host finding and resistance of hybrid host colonies
Behavioral Ecology, 2001Co-Authors: Peter J Neumann, Sarah E. Radloff, Randall Hepburn, Robin F. A. Moritz, Sacha L ReeceAbstract:We studied possible host finding and resistance mechanisms of host colonies in the context of social parasitism by Cape honeybee (Apis mellifera capensis) workers. Workers often join neighboring colonies by drifting, but long-range drifting (dispersal) to colonies far away from the maternal nests also rarely occurs. We tested the impact of queenstate and taxon of mother and host colonies on drifting and dispersing of workers and on the hosting of these workers in A. m. capensis, A. m. scutellata, and their natural hybrids. Workers were paint-marked according to colony and reintroduced into their queenright or queenless mother colonies. After 10 days, 579 out of 12,034 labeled workers were recaptured in foreign colonies. We found that drifting and dispersing represent different behaviors, which were differently affected by taxon and queenstate of both mother and host colonies. Hybrid workers drifted more often than A. m. capensis and A. m. scutellata. However, A. m. capensis workers dispersed more often than A. m. scutellata and the hybrids combined, and A. m. scutellata workers also dispersed more frequently than the hybrids. Dispersers from queenright A. m. capensis colonies were more often found in queenless host colonies and vice versa, indicating active host searching and/or a queenstate-discriminating guarding mechanism. Our data show that A. m. capensis workers disperse significantly more often than other races of A. mellifera, suggesting that dispersing represents a host finding mechanism. The lack of dispersal in hybrids and different hosting mechanisms of foreign workers by hybrid colonies may also be responsible for the stability of the natural hybrid zone between A. m. capensis and A. m. scutellata. Key words: Apis mellifera capensis, Apis mellifera scutellata, honeybee, host finding, hybrids, social parasitism. [Behav Ecol 12:419–428 (2001)]
Michael H Allsopp - One of the best experts on this subject based on the ideXlab platform.
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thelytoky in cape honeybees Apis mellifera capensis is controlled by a single recessive locus
Apidologie, 2017Co-Authors: Denise Aumer, Michael H Allsopp, Michael H G Lattorff, Robin F. A. Moritz, Antje JaroschperlowAbstract:Worker reproduction in Apis mellifera typically leads to haploid males produced via arrhenotokous parthenogenesis. An exception are laying workers of the South African Cape honeybee Apis mellifera capensis. Due to an abnormal spindle rotation during meiosis A. m. capensis workers are able to produce female progeny via thelytokous parthenogenesis. This trait has been suggested to be genetically controlled by a recessive allele at the thelytoky locus (th), but this conclusion was recently challenged by Chapman et al. (2015). To clarify the mode of inheritance for thelytokous parthenogenesis in Cape honeybees, we determined the sex of the offspring of 74 A. m. capensis workers of a single queen from a colony of the endemic wild population at the Cape of Good Hope Nature Reserve. When we tested individual worker reproduction, parthenogenesis was dimorphic, segregating in a Mendelian fashion supporting the single locus model. We could exclude maternal or paternal effects determining the mode of parthenogenesis. A careful re-analysis of the data of Chapman et al. (2015) also revealed that their data do not contradict the one locus model for the inheritance of thelytoky.
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Bacterial diversity in worker adults of Apis mellifera capensis and Apis mellifera scutellata (Insecta: Hymenoptera) assessed using 16S rRNA sequences
Journal of invertebrate pathology, 2003Co-Authors: Ayyamperumal Jeyaprakash, Marjorie A. Hoy, Michael H AllsoppAbstract:High-fidelity PCR of 16S rRNA sequences was used to identify bacteria associated with worker adults of the honeybee subspecies Apis mellifera capensis and Apis mellifera scutellata. An expected approximately 1.5-kb DNA band, representing almost the entire length of the 16S rRNA gene, was amplified from both subspecies and cloned. Ten unique sequences were obtained: one sequence each clustered with Bifidobacterium (Gram-positive eubacteria), Lactobacillus (Gram-positive eubacteria), and Gluconacetobacter (Gram-negative alpha-proteobacteria); two sequences each clustered with Simonsiella (beta-proteobacteria) and Serratia (gamma-proteobacteria); and three sequences each clustered with Bartonella (alpha-proteobacteria). Although the sequences relating to these six bacterial genera initially were obtained from either A. m. capensis or A. m. scutellata or both, newly designed honeybee-specific 16S rRNA primers subsequently amplified all sequences from all individual workers of both subspecies. Attempts to amplify these sequences from eggs have failed. However, the wsp primers designed to amplify Wolbachia DNA from arthropods, including these bees, consistently produced a 0.6-kb DNA band from individual eggs, indicating that amplifiable bacterial DNA was present. Hence, the 10 bacteria could have been acquired orally from workers or from other substrates. This screening of 16S rRNA sequences from A. m. capensis and A. m. scutellata found sequences related to Lactobacillus and Bifidobacterium which previously had been identified from other honeybee subspecies, as well as sequences related to Bartonella, Gluconacetobacter, Simonsiella/Neisseria, and Serratia, which have not been identified previously from honeybees.