Social parasitism by honeybee workers (Apis mellifera capensis Escholtz): host finding and resistance of hybrid host colonies
- Neumann, Peter, Radloff, Sarah E, Moritz, Robin F A, Hepburn, H Randall, Reece, Sacha L
- Authors: Neumann, Peter , Radloff, Sarah E , Moritz, Robin F A , Hepburn, H Randall , Reece, Sacha L
- Date: 2001
- Language: English
- Type: text , Article
- Identifier: vital:6907 , http://hdl.handle.net/10962/d1011860
- Description: 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.
- Full Text:
- Date Issued: 2001
- Authors: Neumann, Peter , Radloff, Sarah E , Moritz, Robin F A , Hepburn, H Randall , Reece, Sacha L
- Date: 2001
- Language: English
- Type: text , Article
- Identifier: vital:6907 , http://hdl.handle.net/10962/d1011860
- Description: 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.
- Full Text:
- Date Issued: 2001
Honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae), of equatorial Africa
- Radloff, Sarah E, Hepburn, H Randall
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 1999
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451885 , vital:75083 , https://hdl.handle.net/10520/AJA10213589_364
- Description: Morphometric and flight dimensional characters of worker honeybees, Apis mellifera Linnaeus, from equatorial Gabon were analysed by multivariate methods to characterize the population. A single morphocluster and a single flight dimension cluster were obtained. When these bees were grouped together with those of other countries of the region, again a single morphoduster and flight cluster were obtained. All of the outlier samples were previously designated as Apis mellifera adansonii Latreille and completely surround the Gabon samples, establishing the same subspecies membership for the latter. The bees of Gabon are morphometrically more homogeneous than in any other area of Africa.
- Full Text:
- Date Issued: 1999
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 1999
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451885 , vital:75083 , https://hdl.handle.net/10520/AJA10213589_364
- Description: Morphometric and flight dimensional characters of worker honeybees, Apis mellifera Linnaeus, from equatorial Gabon were analysed by multivariate methods to characterize the population. A single morphocluster and a single flight dimension cluster were obtained. When these bees were grouped together with those of other countries of the region, again a single morphoduster and flight cluster were obtained. All of the outlier samples were previously designated as Apis mellifera adansonii Latreille and completely surround the Gabon samples, establishing the same subspecies membership for the latter. The bees of Gabon are morphometrically more homogeneous than in any other area of Africa.
- Full Text:
- Date Issued: 1999
Clinal morphometric variation in wild honey bees (Hymenoptera: Apidae) in South Africa
- Steele, G R, Villet, Martin H, Radloff, Sarah E, Hepburn, H Randall
- Authors: Steele, G R , Villet, Martin H , Radloff, Sarah E , Hepburn, H Randall
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442622 , vital:74015 , https://www.jstor.org/stable/2999809
- Description: As a result of side effects of the accidental dispersal of the Cape honey bee, it has become of agroeconomic importance to delineate the region within South Africa where thelytokous worker honey bees occur so that apicultural movement of bees does not exacerbate the problem. Thelytokous workers are believed to be unique to Apis mellifera capensis, so that the problem is to find morphological markers distinguishing this race from its A. m. scutellata neighbours. However, no evidence of the expected hybrid zone demarcating races could be found. Factor analysis revealed only one spherical cluster of samples. Trend surfaces of the local mean morphometric factor scores showed a cline that paralleled latitude, with distortions relating to montane and continental effects. Discriminant function analysis implicated certain mountain ranges in amplifying the effects of latitude. Trend surfaces of local intercolony factor variance showed morphometric homogeneity across most of the country. We conclude that there is only a single population of honey bees in South Africa, and that it shows climate-correlated clinal variation. If the transportation of bees for commercial apiculture is to be successfully regulated to solve the `capensis calamity', further research should focus on the geographical distribution of thelytokous workers rather than on the capensis phenotype. Such workers have a wider distribution than capensis, occurring also at high frequencies around the type locality of A. m. scutellata.
- Full Text:
- Date Issued: 1998
- Authors: Steele, G R , Villet, Martin H , Radloff, Sarah E , Hepburn, H Randall
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442622 , vital:74015 , https://www.jstor.org/stable/2999809
- Description: As a result of side effects of the accidental dispersal of the Cape honey bee, it has become of agroeconomic importance to delineate the region within South Africa where thelytokous worker honey bees occur so that apicultural movement of bees does not exacerbate the problem. Thelytokous workers are believed to be unique to Apis mellifera capensis, so that the problem is to find morphological markers distinguishing this race from its A. m. scutellata neighbours. However, no evidence of the expected hybrid zone demarcating races could be found. Factor analysis revealed only one spherical cluster of samples. Trend surfaces of the local mean morphometric factor scores showed a cline that paralleled latitude, with distortions relating to montane and continental effects. Discriminant function analysis implicated certain mountain ranges in amplifying the effects of latitude. Trend surfaces of local intercolony factor variance showed morphometric homogeneity across most of the country. We conclude that there is only a single population of honey bees in South Africa, and that it shows climate-correlated clinal variation. If the transportation of bees for commercial apiculture is to be successfully regulated to solve the `capensis calamity', further research should focus on the geographical distribution of thelytokous workers rather than on the capensis phenotype. Such workers have a wider distribution than capensis, occurring also at high frequencies around the type locality of A. m. scutellata.
- Full Text:
- Date Issued: 1998
Ecological and morphological differentiation of the honeybees. Apis mellitera linnaeus (Hymenoptera: Apidae). of West Africa
- Radloff, Sarah E, Hepburn, H Randall, Fuchs, S
- Authors: Radloff, Sarah E , Hepburn, H Randall , Fuchs, S
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451832 , vital:75080 , https://hdl.handle.net/10520/AJA10213589_253
- Description: Morphometric characters of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in the sahelian, dry and wet tropical and equatorial regions of western and eastern Africa (mainly between 0 and 15 N latitude, 18 W and 39""E longitude). Two distinct morphocIusters and azoneof hybridization between them were identified. The bees are identified as Apis mellifera adansonii Latreille and A. m. jemenitica Ruttrter. The former subspecies is distributed in the equatorial and wet tropical regions, the latter in the dry tropical and sahelian eco-climatic zones. The hybrid zone extends into the two tropical and savanna biomes and it is suggested that the stability of the hybridization zone is largely the effect of extensive annual fire in the region.
- Full Text:
- Date Issued: 1998
- Authors: Radloff, Sarah E , Hepburn, H Randall , Fuchs, S
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451832 , vital:75080 , https://hdl.handle.net/10520/AJA10213589_253
- Description: Morphometric characters of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in the sahelian, dry and wet tropical and equatorial regions of western and eastern Africa (mainly between 0 and 15 N latitude, 18 W and 39""E longitude). Two distinct morphocIusters and azoneof hybridization between them were identified. The bees are identified as Apis mellifera adansonii Latreille and A. m. jemenitica Ruttrter. The former subspecies is distributed in the equatorial and wet tropical regions, the latter in the dry tropical and sahelian eco-climatic zones. The hybrid zone extends into the two tropical and savanna biomes and it is suggested that the stability of the hybridization zone is largely the effect of extensive annual fire in the region.
- Full Text:
- Date Issued: 1998
Multivariate analysis of honeybee populations, Apis mellifera Linnaeus (Hymenoptera: Apidae), from western central Africa morphometries and pheromones
- Radloff, Sarah E, Hepburn, H Randall
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451963 , vital:75091 , https://hdl.handle.net/10520/AJA10213589_298
- Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations along a transect through three ecological-climatological zones in Cameroon. There are three distinct homogeneous populations and two zones of hybridization. These bees are designated as A. m. adansollii Latreille whose area of distribution is intruded by an A. m. montieola-like montane group of bees and a third group, A. m. jemertitica Ruttner. The delineation of the hybrid zones is supported by intercolonial variance spectra and these significant asymmetries are coincident with transitions between the ecological-climatological zones.
- Full Text:
- Date Issued: 1997
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451963 , vital:75091 , https://hdl.handle.net/10520/AJA10213589_298
- Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations along a transect through three ecological-climatological zones in Cameroon. There are three distinct homogeneous populations and two zones of hybridization. These bees are designated as A. m. adansollii Latreille whose area of distribution is intruded by an A. m. montieola-like montane group of bees and a third group, A. m. jemertitica Ruttner. The delineation of the hybrid zones is supported by intercolonial variance spectra and these significant asymmetries are coincident with transitions between the ecological-climatological zones.
- Full Text:
- Date Issued: 1997
Multivariate analysis of honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae), of the Horn of Africa
- Radloff, Sarah E, Hepburn, H Randall
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451987 , vital:75093 , https://hdl.handle.net/10520/AJA10213589_154
- Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to delineate the honeybee populations of the Horn of Africa. Four discrete and statistically homogeneous populations were identified: A. m. jemenitica Ruttner, A. m. bandasii Mogga, A. m. sudanensis Rashad in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance are interpreted as zones of hybridization between the populations.
- Full Text:
- Date Issued: 1997
- Authors: Radloff, Sarah E , Hepburn, H Randall
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451987 , vital:75093 , https://hdl.handle.net/10520/AJA10213589_154
- Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to delineate the honeybee populations of the Horn of Africa. Four discrete and statistically homogeneous populations were identified: A. m. jemenitica Ruttner, A. m. bandasii Mogga, A. m. sudanensis Rashad in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance are interpreted as zones of hybridization between the populations.
- Full Text:
- Date Issued: 1997
The honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae) of woodland savanna of southeastern Africa
- Radloff, Sarah E, Hepburn, H Randall, Villet, Martin H
- Authors: Radloff, Sarah E , Hepburn, H Randall , Villet, Martin H
- Date: 1997
- Language: English
- Type: Article
- Identifier: vital:6829 , http://hdl.handle.net/10962/d1012341
- Description: The morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to identify discrete populations in the southeastern woodland savanna of Africa. A discrete population in Mozambique is classified as A. m. litorea Smith, a second in Zimbabwe as A. m. scutellata Lepeletier and a third group in southwestern Zambia as A.m. adansonii Latreille. A zone of introgression between the last two subspecies occurs in south-central Zambia and in the Zambezi Valley.
- Full Text:
- Date Issued: 1997
- Authors: Radloff, Sarah E , Hepburn, H Randall , Villet, Martin H
- Date: 1997
- Language: English
- Type: Article
- Identifier: vital:6829 , http://hdl.handle.net/10962/d1012341
- Description: The morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to identify discrete populations in the southeastern woodland savanna of Africa. A discrete population in Mozambique is classified as A. m. litorea Smith, a second in Zimbabwe as A. m. scutellata Lepeletier and a third group in southwestern Zambia as A.m. adansonii Latreille. A zone of introgression between the last two subspecies occurs in south-central Zambia and in the Zambezi Valley.
- Full Text:
- Date Issued: 1997
Discriminant analysis of the honeybee populations of southwestern Africa
- Radloff, Sarah E, Hepburn, H Randall, Robertson, Mark P, Van Hille, Robert P, Davidson, Z, Villet, Martin H
- Authors: Radloff, Sarah E , Hepburn, H Randall , Robertson, Mark P , Van Hille, Robert P , Davidson, Z , Villet, Martin H
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451370 , vital:75044 , https://hdl.handle.net/10520/AJA10213589_176
- Description: The morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in southwestern Africa. There is a discrete homogeneous population in northern South Africa and southern Namibia recognized as the subspecies A m. scutellata, a discrete population in northern Namibia recognized as A m. adansonii and a hybrid population between them.
- Full Text: false
- Date Issued: 1996
- Authors: Radloff, Sarah E , Hepburn, H Randall , Robertson, Mark P , Van Hille, Robert P , Davidson, Z , Villet, Martin H
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451370 , vital:75044 , https://hdl.handle.net/10520/AJA10213589_176
- Description: The morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in southwestern Africa. There is a discrete homogeneous population in northern South Africa and southern Namibia recognized as the subspecies A m. scutellata, a discrete population in northern Namibia recognized as A m. adansonii and a hybrid population between them.
- Full Text: false
- Date Issued: 1996
Multivariate analysis of selected honeybee populations in Africa
- Authors: Radloff, Sarah E
- Date: 1996
- Subjects: Bees -- Africa Bees
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5734 , http://hdl.handle.net/10962/d1005420
- Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus were analysed by multivariate methods to characterise selected honeybee populations along five transects in Africa at a meso-scale level of sampling distance resolution. In some, but not all, areas pheromonal clusters were found to be coincident and concordant with the morphometric clusters, thus indicating that different honeybee traits have dispersed variably among populations. All transects were found to contain areas of significantly high variance. High intracolonial variance was taken to indicate localised genetic variation coupled with out-cross matings. Centroids of high intercolonial variance occured at and between cluster boundaries and were typical of transitions between, and rainfall-temperature discontinuities within, ecological-climatological zones, hence areas of ecological instability. Principal component and stepwise discriminant analysis yielded three morphometric clusters corresponding to A. m. sahariensis and A. m. intermissa in Morocco and to A. m. iberica (with three biometric populations) in Spain, but no pheromone clusters. The combined morphometric and pheromonal variance spectra indicated regions of natural hybridisation along a Sahara-Pyrenees transect. In the Horn of Africa, discrete and statistically homogeneous populations were identified: A. m. jemenitica, A. m. bandasii, A. m. sudanensis in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance were interpreted as zones of hybridisation between the populations. Along a transect in west central Africa, three distinct homogeneous populations and two zones of hybridisation were found. These bees were designated as A. m. adansonii whose area of distribution was intruded by an un-named mountain group of bees and a third group, A. m. jemenitica. The delineation of the hybrid zones was supported by intercolonial variance spectra and these significant asymmetries were found to be coincident with transitions between the ecological-climatological zones. In southwestern Africa, two discrete homogeneous populations and a zone of hybridisation between them were identified: A. m. scutellata in northern South Africa and southern Namibia and A. m. adansonii in northern Namibia. Along a transect in the southeastern woodland savanna of Africa, three discrete populations were classified: A. m. litorea in Mozambique, A. m. scutellata in Zimbabwe and A. m. adansonii in northwestern Zambia. A zone of introgression between the last two subspecies occured in south-central Zambia and in the Zambezi valley.
- Full Text:
- Date Issued: 1996
- Authors: Radloff, Sarah E
- Date: 1996
- Subjects: Bees -- Africa Bees
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5734 , http://hdl.handle.net/10962/d1005420
- Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus were analysed by multivariate methods to characterise selected honeybee populations along five transects in Africa at a meso-scale level of sampling distance resolution. In some, but not all, areas pheromonal clusters were found to be coincident and concordant with the morphometric clusters, thus indicating that different honeybee traits have dispersed variably among populations. All transects were found to contain areas of significantly high variance. High intracolonial variance was taken to indicate localised genetic variation coupled with out-cross matings. Centroids of high intercolonial variance occured at and between cluster boundaries and were typical of transitions between, and rainfall-temperature discontinuities within, ecological-climatological zones, hence areas of ecological instability. Principal component and stepwise discriminant analysis yielded three morphometric clusters corresponding to A. m. sahariensis and A. m. intermissa in Morocco and to A. m. iberica (with three biometric populations) in Spain, but no pheromone clusters. The combined morphometric and pheromonal variance spectra indicated regions of natural hybridisation along a Sahara-Pyrenees transect. In the Horn of Africa, discrete and statistically homogeneous populations were identified: A. m. jemenitica, A. m. bandasii, A. m. sudanensis in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance were interpreted as zones of hybridisation between the populations. Along a transect in west central Africa, three distinct homogeneous populations and two zones of hybridisation were found. These bees were designated as A. m. adansonii whose area of distribution was intruded by an un-named mountain group of bees and a third group, A. m. jemenitica. The delineation of the hybrid zones was supported by intercolonial variance spectra and these significant asymmetries were found to be coincident with transitions between the ecological-climatological zones. In southwestern Africa, two discrete homogeneous populations and a zone of hybridisation between them were identified: A. m. scutellata in northern South Africa and southern Namibia and A. m. adansonii in northern Namibia. Along a transect in the southeastern woodland savanna of Africa, three discrete populations were classified: A. m. litorea in Mozambique, A. m. scutellata in Zimbabwe and A. m. adansonii in northwestern Zambia. A zone of introgression between the last two subspecies occured in south-central Zambia and in the Zambezi valley.
- Full Text:
- Date Issued: 1996