Gerald Kastberger

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Eight microsatellite loci were used to investigate the genetic structure of the giant honeybee (Apis dorsata) population in northeast India. This species migrates seasonally between summer and winter nesting sites, and queens appear to return to their previously occupied site. Furthermore, there is a strong tendency for colonies of this species to aggregate(More)
We report the results of a simple experiment to determine whether honeybees feed their small hive beetle nest parasites. Honeybees incarcerate the beetles in cells constructed of plant resins and continually guard them. The longevity of incarcerated beetles greatly exceeds their metabolic reserves. We show that survival of small hive beetles derives from(More)
Temperature is the most frequently measured physical quantity, second only to time. Infrared (IR) technology has been utilized successfully in astronomy (for a summary,see Hermans-Killam, 2002b) and in industrial and research settings (Gruner, 2002; Madding, 1982, 1989; Wolfe & Zissis, 1993) for decades. However, fairly recent innovations have reduced(More)
1 School of Biological and Conservation Sciences, University of KwaZulu-Natal, Durban, South Africa 2 Institute of Zoology, University Graz, Graz, Austria 3 Maple Leaf Animal Nutrition AgResearch, Maple Leaf Foods, Guelph, ON, Canada 4 Ezemvelo KZN Wildlife, Hluhluwe-iMfolozi Park, KwaZulu-Natal, South Africa 5 Centre for Invasion Biology, Centre for(More)
Recent advances in the noninvasive analyses of plant metabolism include stress imaging techniques, mainly developed for vegetative tissues. We explored if infrared thermography can be used to predict whether a quiescent seed will germinate or die upon water uptake. Thermal profiles of viable, aged, and dead Pisum sativum seeds were recorded, and image(More)
Colony defence in Apis mellifera involves a variety of traits ranging from ‘aggressive’ (e.g. entrance guarding, recruitment of flying guards) to ‘docile’ (e.g. retreating into the nest) expression. We tested 11 colonies of three subspecies (capensis, scutellata, carnica) regarding their defensiveness. Each colony was selected as reportedly ‘aggressive’,(More)
We studied the influence of specially prepared highly diluted thyroxine on the spontaneous tendency of juvenile frogs, which were at the end of thyroxine-controlled metamorphosis, to leave the water and climb onto land. The test dilution with a thyroxine concentration beyond Avogadro's value (dilution thyroxine D30) and the reference (dilution water D30)(More)
Shimmering is a collective defence behaviour in Giant honeybees (Apis dorsata) whereby individual bees flip their abdomen upwards, producing Mexican wave-like patterns on the nest surface. Bucket bridging has been used to explain the spread of information in a chain of members including three testable concepts: first, linearity assumes that individual(More)