Samples of workers of honeybee were collected from 42 colonies in 13 localities in the Lake Chad Basin (parts of Cameroon, Chad, and Nigeria) and analysed using classical morphometry. Measurements of 35 morphological ...Samples of workers of honeybee were collected from 42 colonies in 13 localities in the Lake Chad Basin (parts of Cameroon, Chad, and Nigeria) and analysed using classical morphometry. Measurements of 35 morphological characters of body size, colour and pilosity were taken from 10 workers per colony and the data subjected to one-way analysis of variance (ANOVA), principal components analysis (PCA), hierarchical cluster analysis (HCA), stepwise discriminant analysis (DA) and Pearson’s product-moment correlation analysis. A one-way ANOVA revealed that means of 21 of the morphometric characters differed significantly (p 0.05). The bees formed one cluster in a PCA. However, scatter plots of altitude against principal component 1 of PCA (loaded with characters of body size) revealed an increase of size of the bees along the gradient of the Lake Chad Basin. The coefficient of determination (R2) indicated that 88% and 77% of the variation in size might be explained by altitude in the southeastern and southwestern parts of the basin, respectively. Additionally, there was a very highly significant strong positive relationship between principal component 1 and altitude (r(30) = 0.618, p < 0.0005). Similarly, HCA and DA classified the colonies into three morphoclusters whose distribution closely followed the altitude of the area.展开更多
文摘Samples of workers of honeybee were collected from 42 colonies in 13 localities in the Lake Chad Basin (parts of Cameroon, Chad, and Nigeria) and analysed using classical morphometry. Measurements of 35 morphological characters of body size, colour and pilosity were taken from 10 workers per colony and the data subjected to one-way analysis of variance (ANOVA), principal components analysis (PCA), hierarchical cluster analysis (HCA), stepwise discriminant analysis (DA) and Pearson’s product-moment correlation analysis. A one-way ANOVA revealed that means of 21 of the morphometric characters differed significantly (p 0.05). The bees formed one cluster in a PCA. However, scatter plots of altitude against principal component 1 of PCA (loaded with characters of body size) revealed an increase of size of the bees along the gradient of the Lake Chad Basin. The coefficient of determination (R2) indicated that 88% and 77% of the variation in size might be explained by altitude in the southeastern and southwestern parts of the basin, respectively. Additionally, there was a very highly significant strong positive relationship between principal component 1 and altitude (r(30) = 0.618, p < 0.0005). Similarly, HCA and DA classified the colonies into three morphoclusters whose distribution closely followed the altitude of the area.
