Population structure and morphometric variance of the Apis mellifera scutellata group of honeybees in Africa

Abstract

The honeybee populations of Africa classified as Apis mellifera scutellata Lepeletier were analysed morphometrically using multivariate statistical techniques. The collection consisted of nearly 15,000 worker honeybees from 825 individual colonies at 193 localities in east Africa, extending from South Africa to Ethiopia. Factor analysis established one primary cluster, designated as A. m. scutellata. Morphocluster formation and inclusivity (correct classification) are highly sensitive to sampling distance intervals. Within the A. m. scutellata region are larger bees associated with high altitudes of mountain systems which are traditionally classified as A. m. monticola Smith, but it is evident that these bees do not form a uniform group. Variance characteristics of the morphometric measurements show domains of significantly different local populations. These high variance populations mostly occur at transitional edges of major climatic and vegetational zones, and sometimes with more localised discontinuities in temperature. It is also now evident that those A. m. scutellata introduced nearly fifty years ago into the Neotropics were a particularly homogenous sample, which exhibited all the traits expected in a founder effect or bottleneck population.

Mountain honeybees of Africa

“…That the honeybees of transects 6 and 1 (Lesotho and Ethiopia) are quite distinct from other lower altitude bees surrounding them supports recent interpretations [13,26,27]. However, in this present analysis the largest cluster, comprised of bees from transects 4, 3, 5 and 7 (Malawi, Tanzania, Zimbabwe/Mozambique and Namibia respectively) on the one hand and of transect 2 (Cameroon) on the other, is at odds with recent views [13].…”

“…These combined data, augmented by more recent measurements of honeybees from Zimbabwe, Malawi, Lesotho and Tanzania, were used to analyse the honeybee populations in two different ways. First, a full morphometric analysis of 14 973 worker bees from 825 colonies at 193 localities in East Africa extending from South Africa to Ethiopia was made [26]. But because of the severe consequences of sample size and sampling distance limitations (see Discussion) in masking small biometric groups [25], a more restricted analysis was made on a transect basis.…”

Using geometric morphometrics and standard morphometry to discriminate three honeybee subspecies

“…Unfortunately, the classification functions usually are not published, even when discriminant function analysis is used (Kauhausen and Ruttner, 1986;Radloff and Hepburn, 2000). To assign a colony to one of the three subspecies, a sample of wings from one colony should be obtained and 18 landmarks should be determined.…”

Morphotypes of Varroa destructor collected in Apis mellifera colonies from different geographic locations of Argentina

“…Nevertheless, several studies have registered that in V. destructor species there is a wide phenotypic plasticity within a same mite population (Akimov and Yastrebtsov 1985;Akimov and Zaloznaya 1996;Akimov et al 1990Akimov et al , 2004. A number of publications have been carried out with the aim to study the morphometric variations of A. mellifera populations, and different morphotypes of the bee were established (Buco et al 1987;Radloff and Hepburn 2000;Kandemir et al 2000). However, it is unknown if there are morphologic variations in V. destructor populations affecting different A. mellifera populations.…”