Odour-mediated group organisation and coordination in the termite raiding ant Megaponera analis (Mayr)
Chemical senses, 2020
Visual and olfactory communication are vital for coordinated group hunting in most animals. To hu... more Visual and olfactory communication are vital for coordinated group hunting in most animals. To hunt for prey, the group raiding termite specialist ant Megaponera analis, which lacks good vision must first confirm the presence or absence of conspecific raiders. Here we show that, M. analis uses olfactory cues for intra-specific communication and showed greater preference for conspecific odours over clean air (blank) or odours from its termite prey. Chemical analysis of ant volatiles identified predominantly short-chained hydrocarbons. Electrophysiological analysis revealed differential sensory detection of the odour compounds, which were confirmed in behavioural olfactometric choice assays with odour bouquets collected from major and minor castes, and the two most dominant volatiles n-undecane and n-tridecane. A comparative analysis of the cuticular hydrocarbon profile with those of the short-chained odour bouquet of different populations shows a high divergence in the long chained p...
Worker laying in the absence of an ergatoid queen in the ponerine ant genusPlectroctena
South African Journal of Zoology, 1988
Ergatoid queens (without wings and worker-like) occur in Plectroctena mandibularis and P. conjuga... more Ergatoid queens (without wings and worker-like) occur in Plectroctena mandibularis and P. conjugata. Five nests of these species were incompletely excavated, and an ergatoid was collected in only one of them. The orphaned groups of workers were kept in the laboratory for several months, during which time many eggs were laid. Some of these developed into males. Thus workers can lay haploid eggs in the absence of an ergatoid queen. This was confirmed by dissecting 60 workers from various nests: many of them had mature oocytes in their ovaries, and inseminated individuals were not found. Various data on foraging behaviour and male activity are also presented.
New records of stingless bees (Hymenoptera: Meliponini) in Natal
In 1972 nine colonies of Trigona (Hypotrigona) gribodoi Magretti were found north-west of Empange... more In 1972 nine colonies of Trigona (Hypotrigona) gribodoi Magretti were found north-west of Empangeni, some 100-136 km further south than previously recorded. In 1972-1973, six colonies of T. (Plebeina) denoiti Vachal were found in the same site, about 450 km further south than previously recorded.
Nest structure and thermoregulation in the stingless bee Trigona (Plebeina) denoiti Vachal (Hymenoptera: Apidae)
Nests of the ground-nesting stingless bee Trigona (Plebeina) denoiti were excavated in Natal and ... more Nests of the ground-nesting stingless bee Trigona (Plebeina) denoiti were excavated in Natal and compared with descriptionptions of nests excavated in Tanzania around 1953. A number of differences were found, among them a greater variation in the structure of the brood nest. Although the brood combs were spirally arranged, as in the Tanzanian nests, double as well as single spirals occurred and both types rotated either clockwise or anti-clockwise. The unique features of the nest architecture are discussed.
Etude histologique et examen au microscope electronique a balayage de la glande secretant la pheromone de piste chez deux Crematogaster nord-americains (Formicidae, Mymicinae)
The EAG Response Spectra of Workers and Drones to Queen Honeybee Mandibular Gland Components: The Evolution of a Social Signal
Naturwissenschaften, 1998
In honeybees (Apis mellifera) the mandibular gland pheromone of the queen serves different functi... more In honeybees (Apis mellifera) the mandibular gland pheromone of the queen serves different functions depending on the audience of receivers and the behavioural or colony context. As a sex pheromone it attracts drones to queens at the congregation areas where ...
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