Inheritance of dominance in honeybees (Apis mellifera capensis Esch.)

Summary Hierarchies in worker dominance are well developed in reproductive workers of the Cape honeybee (Apis mellifera capensis Esch.). Elements that influence worker dominance (trophallactic behaviour, fecundity, queen substance content) are mainly genetically determined. The estimated values for the heritabilities in the broader sense range from 0.27 to 0.89. This genetically based hierarchy leads to new insight into the theory of natural selection in honeybees. Besides selection at the colony level, or selection at the level of reproductives, natural selection also operates at the level of the individual worker bee within a colony.     

250-year records of mercury and trace element deposition in two lakes from Cajas National Park,SW Ecuadorian Andes

Environmental Science and Pollution Research - Historical records of trace elements in lake sediments provide source-to-sink information about potentially toxic pollutants across space and time. We...     

(Re-)producing bioassemblages: positionalities of regional bioeconomy development in Finland

ABSTRACT

Bioeconomy is a new political and economic buzzword that frames many proposed pathways to sustainable regional development in Europe, particularly in rural, biomass rich areas. Dissected by research into various strands, visions, shades of “green” and presented by bioeconomy stakeholders through regional examples and self-promoting bio-clusters, the socio-spatial processes of regional assemblages are often ignored in these accounts. Based on a prominent Finnish example, this case study employs the concept of bioassemblage to display the socio-spatial positionalities of regional bioeconomy development in the places of materialisation. Furthermore, it ties the spatial (re-)production of bioassemblages to their role as bioeconomy policy translation loops and consequently provides insights into the processes of bioeconomy policy mobility, translation and mutation. Examining the positionalities in a bioassemblage presents a complex and frequently shifting local environment accompanied by unequal power topologies and means of territorialisation. Shallow policy narratives create problematic mismatches between the “best-practices” employed by policy makers and regional bioeconomy materialisation in the places themselves. While the study makes no assumption on the sustained future of bioeconomy development, it shows that current processes enable the externalisation of risks at industrial sites, restrict wider participation and discredit the important role of institutional actors in development.     

Short-sighted evolution of virulence in parasitic honeybee workers (Apis mellifera capensis Esch.)

The short-sighted selection hypothesis for parasite virulence predicts that winners of within-host competition are poorer at transmission to new hosts. Social parasitism by self-replicating, female-producing workers occurs in the Cape honeybee Apis mellifera capensis, and colonies of other honeybee subspecies are susceptible hosts. We found high within-host virulence but low transmission rates in a clone of social parasitic A. m. capensis workers invading the neighbouring subspecies A. m. scutellata. In contrast, parasitic workers from the endemic range of A. m. capensis showed low within-host virulence but high transmission rates. This suggests a short-sighted selection scenario for the host-parasite co-evolution in the invasive range of the Cape honeybee, probably facilitated by beekeeping-assisted parasite transmission in apiaries.     

No evidence for visual context-dependency of olfactory learning in <Emphasis Type="Italic">Drosophila</Emphasis>

How is behaviour organised across sensory modalities? Specifically, we ask concerning the fruit fly Drosophila melanogaster how visual context affects olfactory learning and recall and whether information about visual context is getting integrated into olfactory memory. We find that changing visual context between training and test does not deteriorate olfactory memory scores, suggesting that these olfactory memories can drive behaviour despite a mismatch of visual context between training and test. Rather, both the establishment and the recall of olfactory memory are generally facilitated by light. In a follow-up experiment, we find no evidence for learning about combinations of odours and visual context as predictors for reinforcement even after explicit training in a so-called biconditional discrimination task. Thus, a ‘true’ interaction between visual and olfactory modalities is not evident; instead, light seems to influence olfactory learning and recall unspecifically, for example by altering motor activity, alertness or olfactory acuity.