Olfactory Learning in the Stingless Bee Melipona eburnea Friese (Apidae: Meliponini)

Neonicotinoid effects on tropical bees: Imidacloprid impairs innate appetitive responsiveness, learning and memory in the stingless bee Melipona quadrifasciata

Together with other anthropogenic factors, pesticides play a major role in pollinator decline worldwide. Most studies on their influence on pollinators have focused on honey bees given the suitability of this insect for controlled behavioral testing and raising. Yet, studies on pesticide impact should also contemplate tropical species, which contribute a major part of biodiversity and which have remained so far neglected. Here we focused on the stingless bee Melipona quadrifasciata and asked if the widely used neonicotinoid imidacloprid disrupts its learning and memory capabilities. We fed stingless bees with 0.1, 0.5 or 1 ng of imidacloprid, tested their innate appetitive responsiveness and trained them to associate odors and sucrose reward using the olfactory conditioning of the proboscis extension response. The same experiments were performed on Africanized honey bees. One hour after intoxication, both species decreased their innate responsiveness to sucrose but the effect was more accentuated in stingless bees. In both species, learning and memory were affected in a dose-dependent manner. These results indicate that pesticides have dramatic consequences on tropical bee species and claim for rational policies regulating their use in the tropics.

Learning and memory in the orange head cockroach (Eublaberus posticus)

This paper describes two experiments aimed at establishing the orange head cockroach (Eublaberus posticus) as a model organism for behavioral research. While many invertebrate models are available, cockroaches have several benefits over others that show impressive behavioral abilities. Most notably, cockroaches are long-lived generalists that can be maintained in controlled indoor laboratory conditions. While the most popular cockroaches in behavioral research, Periplaneta americana and Blattella germanica, have the potential to become domestic pests, our E. posticus is extremely unlikely to escape or infest a human environment, making it a very practical species. In our first experiment, we investigated the ability of E. posticus to associate novel odors with appetitive and aversive solutions. They quickly learned to approach odors associated with a dog food sucrose solution and learned to avoid odors associated with salt water. The second experiment repeated the methods of the first experiment, while also testing retained preferences for conditioned odors, from 15 to 1,215 minutes after the conditioning procedure ended. We found that preferences for odors associated with food were strongest 45 minutes after training, then decreased as a function of time. Our work is the first to show associative learning and memory in the orange head cockroach. Findings are discussed in comparison to other invertebrate models as well as to other cockroach research.

Behaviorist approaches to investigating memory and learning: A primer for synthetic biology and bioengineering

The fields of developmental biology, biomedicine, and artificial life are being revolutionized by advances in synthetic morphology. The next phase of synthetic biology and bioengineering is resulting in the construction of novel organisms (biobots), which exhibit not only morphogenesis and physiology but functional behavior. It is now essential to begin to characterize the behavioral capacity of novel living constructs in terms of their ability to make decisions, form memories, learn from experience, and anticipate future stimuli. These synthetic organisms are highly diverse, and often do not resemble familiar model systems used in behavioral science. Thus, they represent an important context in which to begin to unify and standardize vocabulary and techniques across developmental biology, behavioral ecology, and neuroscience. To facilitate the study of behavior in novel living systems, we present a primer on techniques from the behaviorist tradition that can be used to probe the functions of any organism – natural, chimeric, or synthetic – regardless of the details of their construction or origin. These techniques provide a rich toolkit for advancing the fields of synthetic bioengineering, evolutionary developmental biology, basal cognition, exobiology, and robotics.