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:
- 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:
Sexual dimorphism and tail-length in widowbirds and bishopbirds (Ploeeidae: Euplectes spp.): a reassessment
- Craig, Adrian J F K, Villet, Martin H
- Authors: Craig, Adrian J F K , Villet, Martin H
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442306 , vital:73974 , https://doi.org/10.1111/j.1474-919X.1998.tb04551.x
- Description: No evidence for sexual selection in the evolution of tail‐length or wing‐length in widow birds and bishopbirds (genus Euplectes) was found when the methods used by previous authors were applied to a larger set of data. Nuptial tail‐length dimorphism scaled with body size dimorphism except in Euplectes progne, and interpopulation variation in taillength could be explained by genetic drift alone. Wing‐length appears to be under stabilizing selection and scales allometrically with body size, with no relation to tail‐length unless E. progne is included in the analysis.
- Full Text:
- Authors: Craig, Adrian J F K , Villet, Martin H
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442306 , vital:73974 , https://doi.org/10.1111/j.1474-919X.1998.tb04551.x
- Description: No evidence for sexual selection in the evolution of tail‐length or wing‐length in widow birds and bishopbirds (genus Euplectes) was found when the methods used by previous authors were applied to a larger set of data. Nuptial tail‐length dimorphism scaled with body size dimorphism except in Euplectes progne, and interpopulation variation in taillength could be explained by genetic drift alone. Wing‐length appears to be under stabilizing selection and scales allometrically with body size, with no relation to tail‐length unless E. progne is included in the analysis.
- Full Text:
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