Insect sentience and the rise of a new inclusive ethics

Welfare protections for vertebrates are grounded in the belief that vertebrates are sentient and capable of feeling whereas invertebrates are not. We agree with Mikhalevich & Powell that the exclusion of small-brained invertebrates from bioethics is not warranted by the current state of the scientific evidence. The choice to promote protection for certain invertebrates should be based on the Animal Sentience Precautionary Principle (ASPP). This principle should not prevent us from conducting experimental research with non-human animals to advance knowledge. However, we believe that it is important to outline practical guidelines to manage the wellbeing of invertebrates, while accumulating further evidence on their inner life

Reuse of old nests by the European paper wasp Polistes dominula (Hymenoptera Vespidae).

Similarly to the majority of social insects the nest represents for paper wasps an important component of the colony life and it is intimately linked to its social organization. When, in spring, future foundresses emerge from hibernacula they can choose between building a new nest and reusing an old one. Refurbishing the old nest in order to prepare it for a new breeding season cycle has already been observed in few species of paper wasps. In the present study we found that although the majority of Polistes dominula foundresses prefer to start new colonies early in the spring, an eight percent of nests were reused in our population. We speculate that reusing old nests might allow foundresses to save energy and gain time, but in turn it might also impose additional costs such as the risk of incurring in a higher pathogen pressure. Our data shows that the habits of reusing old nest is widespread in P. dominula but further experiments are required to test both these hypotheses and to clarify pros and cons of reusing old nests in this Polistes paper wasp species

Reuse of old nests by the European paper wasp Polistes dominula (Hymenoptera Vespidae).

Similarly to the majority of social insects the nest represents for paper wasps an important component of the colony life and it is intimately linked to its social organization. When, in spring, future foundresses emerge from hibernacula they can choose between building a new nest and reusing an old one. Refurbishing the old nest in order to prepare it for a new breeding season cycle has already been observed in few species of paper wasps. In the present study we found that although the majority of Polistes dominula foundresses prefer to start new colonies early in the spring, an eight percent of nests were reused in our population. We speculate that reusing old nests might allow foundresses to save energy and gain time, but in turn it might also impose additional costs such as the risk of incurring in a higher pathogen pressure. Our data shows that the habits of reusing old nest is widespread in P. dominula but further experiments are required to test both these hypotheses and to clarify pros and cons of reusing old nests in this Polistes paper wasp species

Nectar non-protein amino acids (NPAAs) do not change nectar palatability but enhance learning and memory in honey bees

Floral nectar is a pivotal element of the intimate relationship between plants and pollinators. Nectars are composed of a plethora of nutritionally valuable compounds but also hundreds of secondary metabolites (SMs) whose function remains elusive. Here we performed a set of behavioural experiments to study whether five ubiquitous nectar non-protein amino acids (NPAAs: β-alanine, GABA, citrulline, ornithine and taurine) interact with gustation, feeding preference, and learning and memory in Apis mellifera. We showed that foragers were unable to discriminate NPAAs from water when only accessing antennal chemo-tactile information and that freely moving bees did not exhibit innate feeding preferences for NPAAs. Also, NPAAs did not alter food consumption or longevity in caged bees over 10 days. Taken together our data suggest that natural concentrations of NPAAs did not alter nectar palatability to bees. Olfactory conditioning assays showed that honey bees were more likely to learn a scent when it signalled a sucrose reward containing either β-alanine or GABA, and that GABA enhanced specific memory retention. Conversely, when ingested two hours prior to conditioning, GABA, β-alanine, and taurine weakened bees’ acquisition performances but not specific memory retention, which was enhanced in the case of β-alanine and taurine. Neither citrulline nor ornithine affected learning and memory. NPAAs in nectars may represent a cooperative strategy adopted by plants to attract beneficial pollinators