The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform
Francis L. W. Ratnieks - One of the best experts on this subject based on the ideXlab platform.
-
ORIGINAL PAPER Co-occurrence of three types of egg policing in the Norwegian wasp Dolichovespula norwegica
2013Co-Authors: Francis L. W. Ratnieks, Adam Tofilski, Tom Wenseleers, Wim Bonckaert, Fabio S. Nascimento, Johan Billen, T. Wenseleers, A. TofilskiAbstract:Abstract In insect societies, workers often try to challenge the reproductive monopoly of the queen by laying their own eggs. Successful worker reproduction, however, is frequently prevented by queen policing or worker policing, whereby either the mother queen or non-reproductive workers selectively kill worker-laid eggs. Recently, a third mechanism—“selfish ” worker policing—has also been described in which the workers selectively police workerlaid eggs but also lay eggs themselves. Here, we present results from the monogynous wasp Dolichovespula norwegica, which show that all three kinds of policing—queen policing, worker policing and “selfish ” worker policing—co-occur. The net effect of these three kinds of policing collectively favoured Communicated by R. Moritz Electronic supplementary material The online version of this article (doi:10.1007/s00265-010-1064-3) contains supplementary material, which is available to authorized users
-
Co-occurrence of three types of egg policing in the Norwegian wasp Dolichovespula norwegica
Behavioral Ecology and Sociobiology, 2010Co-Authors: Wim Bonckaert, Francis L. W. Ratnieks, Adam Tofilski, Fabio S. Nascimento, Johan Billen, Tom WenseleersAbstract:In insect societies, workers often try to challenge the reproductive monopoly of the queen by laying their own eggs. Successful worker reproduction, however, is frequently prevented by queen policing or worker policing, whereby either the mother queen or non-reproductive workers selectively kill worker-laid eggs. Recently, a third mechanism—“selfish” worker policing—has also been described in which the workers selectively police worker-laid eggs but also lay eggs themselves. Here, we present results from the monogynous wasp Dolichovespula norwegica, which show that all three kinds of policing—queen policing, worker policing and “selfish” worker policing—co-occur. The net effect of these three kinds of policing collectively favoured the queen’s reproduction, as within 1 day 44% of the worker-laid eggs versus only 8% of the queen-laid eggs were eaten. Of the worker-laid eggs that were killed by workers, approximately two thirds were eaten by the reproductive workers even though these made up only a small proportion, 8%, of the work force. This means that policing workers obtained both direct fitness benefits as well as indirect (inclusive) fitness. In addition, we show that worker policing was carried out by a limited, specialised set of workers that was estimated to constitute approximately one quarter of the whole colony and of which 66% were non-reproductive.
-
Queen and worker policing in the tree wasp Dolichovespula sylvestris
Behavioral Ecology and Sociobiology, 2005Co-Authors: Tom Wenseleers, Adam Tofilski, Francis L. W. RatnieksAbstract:Insect societies are sometimes exploited by workers who reproduce selfishly rather than help to rear the queen’s offspring. This causes a conflict-of-interest with the mother queen and, frequently, with the non-reproductive workers as well. One mechanism that can reduce conflict is policing, whereby either the queen or other workers aggress egg-laying workers or destroy worker-laid eggs. Here we present the first direct observations of queen and worker policing in natural, unmanipulated colonies of a social insect, the tree wasp Dolichovespula sylvestris. Worker reproduction was common, with workers producing 50% of all male eggs. However, most worker-laid eggs, 91%, were policed within 1 day, whereas most queen-laid eggs, 96%, remained unharmed. The workers were responsible for 51% of all policing events and the queen for 49%. The workers and mother queen also commonly aggressed ovipositing workers, and successfully prevented them from depositing eggs in 14% and 6% of all attempted ovipositions. Hence, both queen policing and worker policing occur and policing acts via two distinct mechanisms: selective destruction of worker-laid eggs and aggression of ovipositing workers. At a general level, our study shows that both centralized and decentralized control can act together to suppress conflict within social groups.
-
Queen and worker policing in the tree wasp Dolichovespula sylvestris
'Springer Science and Business Media LLC', 2005Co-Authors: Wenseleers Tom, Tofilski Adam, Francis L. W. RatnieksAbstract:Insect societies are sometimes exploited by workers who reproduce selfishly rather than help to rear the queenrsquos offspring. This causes a conflict-of-interest with the mother queen and, frequently, with the non-reproductive workers as well. One mechanism that can reduce conflict is policing, whereby either the queen or other workers aggress egg-laying workers or destroy worker-laid eggs. Here we present the first direct observations of queen and worker policing in natural, unmanipulated colonies of a social insect, the tree wasp Dolichovespula sylvestris. Worker reproduction was common, with workers producing 50% of all male eggs. However, most worker-laid eggs, 91%, were policed within 1 day, whereas most queen-laid eggs, 96%, remained unharmed. The workers were responsible for 51% of all policing events and the queen for 49%. The workers and mother queen also commonly aggressed ovipositing workers, and successfully prevented them from depositing eggs in 14% and 6% of all attempted ovipositions. Hence, both queen policing and worker policing occur and policing acts via two distinct mechanisms: selective destruction of worker-laid eggs and aggression of ovipositing workers. At a general level, our study shows that both centralized and decentralized control can act together to suppress conflict within social groups.status: publishe
-
Colony kin structure and male production in Dolichovespula wasps.
Molecular ecology, 2001Co-Authors: Kevin R. Foster, Francis L. W. Ratnieks, Niclas Gyllenstrand, Peter ThorénAbstract:In annual hymenopteran societies headed by a single outbred queen, paternity (determined by queen mating frequency and sperm use) is the sole variable affecting colony kin structure and is therefore a key predictor of colony reproductive characteristics. Here we investigate paternity and male production in five species of Dolichovespula wasps. Twenty workers from each of 10 colonies of each of five species, 1000 workers in total, were analysed at three DNA microsatellite loci to estimate paternity. To examine the relationship between kin structure and reproductive behaviour, worker ovary activation was assessed by dissection and the maternal origin of adult males was assessed by DNA microsatellites. Effective paternity was low in all species (D.media 1.08, D. maculata 1.0, D. sylvestris 1.15, D. norwegica 1.08 and D. saxonica 1.35), leading to the prediction of queen?worker conflict over male production. In support of this, workers with full-size eggs in their ovaries (four out of five species) and adult males that were workers? sons (all five species) were found in queenright colonies. However, workers were only responsible for a minority of male production (D.media 7.4%, D. maculata 20.9%, D. sylvestris 9.8%, D. norwegica 2.6% and D. saxonica 34.6%) suggesting that the queen maintains considerable reproductive power over the workers. Kin structure and reproductive conflict in Dolichovespula contrast with their sister group Vespula. Dolichovespula is characterized by low paternity, worker reproduction, and queen?worker conflict and Vespula by high paternity, effective worker policing and absence of worker reproduction. The trend revealed by this comparison is as predicted by kin selection theory suggesting that colony kin structure has been pivotal in the evolution of the yellowjacket wasps.
Jessica L. Metcalf - One of the best experts on this subject based on the ideXlab platform.
-
mating frequency within colony relatedness and male production in a yellow jacket wasp Dolichovespula arenaria
Molecular Ecology, 2004Co-Authors: Brian J. Freiburger, Michael D. Breed, Jessica L. MetcalfAbstract:We examined the mating frequencies of queens in a social wasp, Dolichovespula arenaria (Vespinae) using DNA microsatellites. Five of the seven colonies supported the hypothesis of single mating by queens. The other two colonies supported two and three matings, with effective paternity of 1.48 and 1.91. Mean worker relatedness was 0.77 +/- 0.09. In two of the four male-containing colonies, all were likely progeny of the queen. In the other two colonies workers produced 8 and 14% of the male wasps. Overall, 94.3% of the male wasps were likely progeny of the queen. These patterns are consistent with published studies of vespine wasps.
-
Mating frequency, within‐colony relatedness and male production in a yellow jacket wasp, Dolichovespula arenaria
Molecular ecology, 2004Co-Authors: Brian J. Freiburger, Michael D. Breed, Jessica L. MetcalfAbstract:We examined the mating frequencies of queens in a social wasp, Dolichovespula arenaria (Vespinae) using DNA microsatellites. Five of the seven colonies supported the hypothesis of single mating by queens. The other two colonies supported two and three matings, with effective paternity of 1.48 and 1.91. Mean worker relatedness was 0.77 +/- 0.09. In two of the four male-containing colonies, all were likely progeny of the queen. In the other two colonies workers produced 8 and 14% of the male wasps. Overall, 94.3% of the male wasps were likely progeny of the queen. These patterns are consistent with published studies of vespine wasps.
Kevin R. Foster - One of the best experts on this subject based on the ideXlab platform.
-
vulgarogamasus sphecophilus cooreman comb nov acari mesostigmata parasitidae a redescription and new hymenopteran association
Zootaxa, 2009Co-Authors: Anne S Baker, Kevin R. FosterAbstract:Eugamasus sphecophilus Cooreman is transferred to the genus Vulgarogamasus, redescribed (female, male and deutonymph), and proposed as a senior synonym of Poecilochirus britannicus Hyatt. The male and female deutonymph of the species are distinguished for the first time. Vulgarogamasus sphecophilus comb. nov. is recorded in association with the social wasp Dolichovespula saxonica for the first time, where it was observed causing significant egg mortality. As the result of the new synonymy, the geographical range of V. sphecophilus now includes the British Isles.
-
Colony kin structure and male production in Dolichovespula wasps.
Molecular ecology, 2001Co-Authors: Kevin R. Foster, Francis L. W. Ratnieks, Niclas Gyllenstrand, Peter ThorénAbstract:In annual hymenopteran societies headed by a single outbred queen, paternity (determined by queen mating frequency and sperm use) is the sole variable affecting colony kin structure and is therefore a key predictor of colony reproductive characteristics. Here we investigate paternity and male production in five species of Dolichovespula wasps. Twenty workers from each of 10 colonies of each of five species, 1000 workers in total, were analysed at three DNA microsatellite loci to estimate paternity. To examine the relationship between kin structure and reproductive behaviour, worker ovary activation was assessed by dissection and the maternal origin of adult males was assessed by DNA microsatellites. Effective paternity was low in all species (D.media 1.08, D. maculata 1.0, D. sylvestris 1.15, D. norwegica 1.08 and D. saxonica 1.35), leading to the prediction of queen?worker conflict over male production. In support of this, workers with full-size eggs in their ovaries (four out of five species) and adult males that were workers? sons (all five species) were found in queenright colonies. However, workers were only responsible for a minority of male production (D.media 7.4%, D. maculata 20.9%, D. sylvestris 9.8%, D. norwegica 2.6% and D. saxonica 34.6%) suggesting that the queen maintains considerable reproductive power over the workers. Kin structure and reproductive conflict in Dolichovespula contrast with their sister group Vespula. Dolichovespula is characterized by low paternity, worker reproduction, and queen?worker conflict and Vespula by high paternity, effective worker policing and absence of worker reproduction. The trend revealed by this comparison is as predicted by kin selection theory suggesting that colony kin structure has been pivotal in the evolution of the yellowjacket wasps.
-
Paternity, reproduction and conflict in vespine wasps: a model system for testing kin selection predictions
Behavioral Ecology and Sociobiology, 2001Co-Authors: Kevin R. Foster, Francis L. W. RatnieksAbstract:The Vespinae wasps (Vespa, Provespa, Dolichovespula, and Vespula) are an excellent group for testing kin selection predictions. There is considerable variation in kin structure and conflict resolution in a group of known phylogeny where all species have a similar basic biology: morphologically distinct queens and workers, and annual nests headed by a single queen. Vespine kin structure can be described by a single variable "effective paternity", which is defined by queen mating frequency and sperm use. Low effective paternity, which causes high worker relatedness, is basal in the group (Vespa, Dolichovespula), with high paternity (ca >2) restricted to Vespula whose queens mate more and use sperm more equally. Paternity variation correlates well with observed patterns of reproduction and conflict. As predicted by theory, male production by workers is common in Dolichovespula but not in Vespula where worker policing occurs (Vespula vulgaris). The theory is also supported by intercolony variation in Dolichovespula, with facultative worker policing (Dolichovespula saxonica) and sex allocation biasing by workers (D. arenaria) occurring in response to paternity. In addition, queen loss in reproductive colonies of nine species is negatively correlated with paternity, in line with the prediction that matricide is only expected at low paternity. However, paternity does not explain the reproductive characteristics of Vespa crabro. Although paternity in V. crabro is only 1.1, the same as the mean in six Dolichovespula species, its reproductive behaviour is different from Dolichovespula. More like Vespula, V. crabro has worker policing, workers that rarely have active ovaries, and little queen loss in reproductive-phase colonies.
-
Inclusive fitness theory: novel predictions and tests in eusocial Hymenoptera
2001Co-Authors: Francis L. W. Ratnieks, Thibaud Monnin, Kevin R. FosterAbstract:Hamilton?s ?rst papers concerned social evolution and revolutionized our understanding of reproductive con?ict in insect societies. The revolution continues. Recent research at the University of Shef?eld has investigated two topics previously not considered from an inclusive ?tness perspective: dominance hierarchies and queen? worker caste con?ict. The theory makes predictions close to that occurring in hierarchies of Dinoponera queenless ants and queen overproduction in Melipona bees. An earlier prediction, that multiple paternity favours worker policing, is supported by research on Vespula and Dolichovespula wasps. However, worker policing also occurs in the hornet, Vespa crabro, which has low paternity (effective queen mating 1.1). Worker policing in Vespinae wasps has two novel facultative features. In Dolichovespula saxonica, worker policing occurs in colonies headed by a multiple-mated queen but not by a single-mated queen. In Vespa crabro, queenless colonies accept worker-laid eggs but reject queen-laid eggs, probably because queen supersedure does not occur but queen parasitism does
-
Facultative worker policing in a wasp.
Nature, 2000Co-Authors: Kevin R. Foster, Francis L. W. RatnieksAbstract:Kin-selection theory predicts that in social-insect colonies where the queen has mated multiple times, the workers will enforce cooperation by policing each other's reproduction1,2,3,4. We have discovered a species, the wasp Dolichovespula saxonica, in which some queens mate once and others mate many times, and in which workers frequently attempt reproduction, allowing this prediction to be tested directly. We find that multiple mating by the queen leads to mutual policing by workers, whereas single mating does not.
Tom Wenseleers - One of the best experts on this subject based on the ideXlab platform.
-
ORIGINAL PAPER Co-occurrence of three types of egg policing in the Norwegian wasp Dolichovespula norwegica
2013Co-Authors: Francis L. W. Ratnieks, Adam Tofilski, Tom Wenseleers, Wim Bonckaert, Fabio S. Nascimento, Johan Billen, T. Wenseleers, A. TofilskiAbstract:Abstract In insect societies, workers often try to challenge the reproductive monopoly of the queen by laying their own eggs. Successful worker reproduction, however, is frequently prevented by queen policing or worker policing, whereby either the mother queen or non-reproductive workers selectively kill worker-laid eggs. Recently, a third mechanism—“selfish ” worker policing—has also been described in which the workers selectively police workerlaid eggs but also lay eggs themselves. Here, we present results from the monogynous wasp Dolichovespula norwegica, which show that all three kinds of policing—queen policing, worker policing and “selfish ” worker policing—co-occur. The net effect of these three kinds of policing collectively favoured Communicated by R. Moritz Electronic supplementary material The online version of this article (doi:10.1007/s00265-010-1064-3) contains supplementary material, which is available to authorized users
-
Co-occurrence of three types of egg policing in the Norwegian wasp Dolichovespula norwegica
Behavioral Ecology and Sociobiology, 2010Co-Authors: Wim Bonckaert, Francis L. W. Ratnieks, Adam Tofilski, Fabio S. Nascimento, Johan Billen, Tom WenseleersAbstract:In insect societies, workers often try to challenge the reproductive monopoly of the queen by laying their own eggs. Successful worker reproduction, however, is frequently prevented by queen policing or worker policing, whereby either the mother queen or non-reproductive workers selectively kill worker-laid eggs. Recently, a third mechanism—“selfish” worker policing—has also been described in which the workers selectively police worker-laid eggs but also lay eggs themselves. Here, we present results from the monogynous wasp Dolichovespula norwegica, which show that all three kinds of policing—queen policing, worker policing and “selfish” worker policing—co-occur. The net effect of these three kinds of policing collectively favoured the queen’s reproduction, as within 1 day 44% of the worker-laid eggs versus only 8% of the queen-laid eggs were eaten. Of the worker-laid eggs that were killed by workers, approximately two thirds were eaten by the reproductive workers even though these made up only a small proportion, 8%, of the work force. This means that policing workers obtained both direct fitness benefits as well as indirect (inclusive) fitness. In addition, we show that worker policing was carried out by a limited, specialised set of workers that was estimated to constitute approximately one quarter of the whole colony and of which 66% were non-reproductive.
-
Queen and worker policing in the tree wasp Dolichovespula sylvestris
Behavioral Ecology and Sociobiology, 2005Co-Authors: Tom Wenseleers, Adam Tofilski, Francis L. W. RatnieksAbstract:Insect societies are sometimes exploited by workers who reproduce selfishly rather than help to rear the queen’s offspring. This causes a conflict-of-interest with the mother queen and, frequently, with the non-reproductive workers as well. One mechanism that can reduce conflict is policing, whereby either the queen or other workers aggress egg-laying workers or destroy worker-laid eggs. Here we present the first direct observations of queen and worker policing in natural, unmanipulated colonies of a social insect, the tree wasp Dolichovespula sylvestris. Worker reproduction was common, with workers producing 50% of all male eggs. However, most worker-laid eggs, 91%, were policed within 1 day, whereas most queen-laid eggs, 96%, remained unharmed. The workers were responsible for 51% of all policing events and the queen for 49%. The workers and mother queen also commonly aggressed ovipositing workers, and successfully prevented them from depositing eggs in 14% and 6% of all attempted ovipositions. Hence, both queen policing and worker policing occur and policing acts via two distinct mechanisms: selective destruction of worker-laid eggs and aggression of ovipositing workers. At a general level, our study shows that both centralized and decentralized control can act together to suppress conflict within social groups.
Brian J. Freiburger - One of the best experts on this subject based on the ideXlab platform.
-
mating frequency within colony relatedness and male production in a yellow jacket wasp Dolichovespula arenaria
Molecular Ecology, 2004Co-Authors: Brian J. Freiburger, Michael D. Breed, Jessica L. MetcalfAbstract:We examined the mating frequencies of queens in a social wasp, Dolichovespula arenaria (Vespinae) using DNA microsatellites. Five of the seven colonies supported the hypothesis of single mating by queens. The other two colonies supported two and three matings, with effective paternity of 1.48 and 1.91. Mean worker relatedness was 0.77 +/- 0.09. In two of the four male-containing colonies, all were likely progeny of the queen. In the other two colonies workers produced 8 and 14% of the male wasps. Overall, 94.3% of the male wasps were likely progeny of the queen. These patterns are consistent with published studies of vespine wasps.
-
Mating frequency, within‐colony relatedness and male production in a yellow jacket wasp, Dolichovespula arenaria
Molecular ecology, 2004Co-Authors: Brian J. Freiburger, Michael D. Breed, Jessica L. MetcalfAbstract:We examined the mating frequencies of queens in a social wasp, Dolichovespula arenaria (Vespinae) using DNA microsatellites. Five of the seven colonies supported the hypothesis of single mating by queens. The other two colonies supported two and three matings, with effective paternity of 1.48 and 1.91. Mean worker relatedness was 0.77 +/- 0.09. In two of the four male-containing colonies, all were likely progeny of the queen. In the other two colonies workers produced 8 and 14% of the male wasps. Overall, 94.3% of the male wasps were likely progeny of the queen. These patterns are consistent with published studies of vespine wasps.
-
Colony Kin Relatedness and Male Production in Dolichovespula Arenaria
2003Co-Authors: Brian J. FreiburgerAbstract:Abstract : The number of times a female social insect mates has important implications for the evolution and maintenance of sociality. My study focuses on queen mating frequency in a social wasp, Dolichovespula arenaria (Order: Hymenoptera, Family: Vespidae, Subfamily: Vespinae). Queen mating frequencies are known for only a few species of vespine wasps; adding data for additional species will help to establish trends in social evolution within this clade. Colonies of D. arenaria were collected in the subalpine zone of the Front Range of the Colorado Rocky Mountains in 2002 and 2003. Worker, queen, and male genotypes were analyzed using three DNA microsatellite loci Rufa 5, 13 and 15 (Thoren et at. 1995, Foster et at. 2001). Worker relatedness ranged from 0.57 to 0.83 within each of the seven colonies sampled with a mean relatedness of 0.77. Five of the seven colonies supported the hypothesis of single mating by queens. In one colony two and in one colony three matings were likely. Effective paternity in these two colonies was 1.48 and 1.91, respectively. Four colonies sampled contained males that were assigned as worker or queen progeny using both the exclusion and maximum likelihood methods; each method yielded similar results. In two of these colonies, all males were likely progeny of the queen. In the other two colonies worker produced 8 to 24% of the males. Overall 91.5% of the males in the population were likely progeny of the queen. These patterns are consistent with published studies of vespine wasps.