The matter of sampling distance and confidence levels in the subspecific classification of honeybees, Apis mellifera L.

The effects of variations in sampling distance and confidence levels on the subspecific classification of honeybees were analysed by subjecting colony means of morphometric characters to factor analysis and stepwise discrimin ant analysis procedures. Analyses of honeybees from a transect from Morocco through Spain and another from Tanzania through Sudan show that the greate r the distance between samples, the more distinct the morphoclusters. The l ength of the transect may obscure small biometric groups if the between-gro up variation is considerably larger than the within-group variation. Varyin g the levels of confidence applied to the ellipses and the discriminant a p osteriori probabilities from low to high decreased the number of colonies c orrectly assignable to morphoclusters. Thus, sampling distance, transect le ngth, confidence levels and their a posteriori probabilities are all just a s crucial to the structure and resolution of honeybees morphoclusters as ar e sample size and character suites. (C) Inra/DIB/AGIB/Elsevier, Paris.