The effects of dietary proline, ß-alanine, and γ-aminobutyric acid (GABA) on the nest construction behavior in the Oriental hornet (Vespa orientalis).

Adult wasps primary food resource is larval saliva. This liquid secretion consists mainly of amino acids and carbohydrates processed from the prey brought to the colony by the foragers. However, adults also regularly consume floral nectar. The nectar's most abundant proteinogenic amino acid is proline, and the two most abundant non-proteinogenic amino acids are ß-alanine and GABA. These three amino acids are also common in larval saliva. Here, we study the effect of these dietary amino acids on the physiology and nest construction behavior of the Oriental hornet. Our results reveal their deleterious effects, especially at high concentrations: ß-alanine and GABA consumption reduced the hornets' lifespan and completely inhibited their construction behavior; while proline induced a similar but more moderate effect. At low concentrations, these amino acids had no effect on hornet survival but did slow down the nest construction process. Using carbon isotopically labeled amino acids, we show that, unlike proline, ß-alanine is stored in most body tissues (brain, muscles, and fat body), suggesting that it is rapidly metabolized after consumption. Our findings demonstrate how a single amino acid can impact the fitness of a nectarivore insect.

Juvenile hormone functions as a metabolic rate accelerator in bumble bees (Bombus terrestris).

Juvenile hormone (JH) is a modulator of many physiological transitions in insects, including molting, metamorphosis, diapause, and reproduction. These processes often include metabolic changes. Here we show that JH accelerates metabolic rate in bumble bees (Bombus terrestris). We reduced JH levels in worker bumble bees by removing their corpora allata (allatectomy) and elevated JH levels in queens through a topical application of JH-III. Natural and high JH levels increased the metabolic rate in both workers and queens and triggered an increased protein turnover rate. Following the treatments, JH also caused an increase in food consumption and a reduction in lipid levels and flight muscle mass of queens, and a reduction in lipids levels in workers. Furthermore, the topical application of a JH analog to queens prior to their diapause caused a decline in their survival of diapause. These findings support the hypothesis that JH acts as a metabolic rate accelerator, initiating a resource shift in bumble bees, and thereby reducing diapause survival in queens. Based on previous studies on JH we suggest that, additional to its behavioral or physiological effects, JH's function as an accelerator of metabolic processes is conserved across different life stages and insect species.

The effect of local species composition on the distribution of an avian invader.

Estimating the potential distribution of invasive species has been primarily achieved by employing species distribution models (SDM). Recently introduced joint species distribution models (JSDM) that include species interactions are expected to improve model output. Here we compare the predictive ability of SDM and JSDM by modelling the distribution of one of the most prolific avian invaders in the world, the common myna (Acridotheres tristis), in a recent introduction in Israel. Our results indicate that including information on the local species composition did not improve model accuracy, possibly because of the unique characteristics of this species that include broad environmental tolerance and behavior flexibility. However, the JSDM provided insights into co-occurrence patterns of common mynas and their local heterospecifics, suggesting that at this time point, there is no evidence of species exclusion by common mynas. Our findings suggest that the invasion potential of common mynas depends greatly on urbanization and less so on the local species composition and reflect the major role of anthropogenic impact in increasing the distribution of avian invaders.

Taxonomic revision of Israeli snakes belonging to the Platyceps rhodorachis species complex (Reptilia: Squamata: Colubridae).

The Platyceps rhodorachis species complex encompasses a widespread group of morphologically similar colubrid snakes. The number and identities of species from this complex in Israel have recently been debated. Studies from the previous decade concluded that there are two species in Israel and its vicinity (compared with one previously recognized), but their identity remained contested. We estimated the number of species and their taxonomic identity using morphological and molecular data. We found some evidence for clinal variation in many of the characters used to differentiate the species, and a great overlap in traits of putative species. Genetic data revealed very low sequence divergence, with all putative species being paraphyletic. Platyceps rogersi emerged as genetically closer to Platyceps saharicus rather than to its putative conspecific, P. karelini. The phylogenetic and taxonomic results thus indicate that the Israeli populations of the P. rhodorachis complex all belong to a single species, Platyceps saharicus (Schätti McCarthy 2004).

Genetic Knowledge within a National Australian Sample: Comparisons with Other Diverse Populations.

BACKGROUND: Genetic knowledge, which plays important functions in our understanding of science, health, social groupings, and even behaviour, has been evaluated in past studies with various populations. This wide reach of genetics means that different types of items are used to assess genetic knowledge, which restricts meaningful comparisons across time- and locale-based studies. AIM: The present study addresses this limitation by recruiting an Australia-wide sample and evaluating their genetic knowledge using items sourced from four diverse samples. METHOD: Seven hundred and eighty Australians completed a variety of items assessing their genetic knowledge as well as several demographic indicators. RESULTS: The results show superior overall genetic knowledge in the current sample compared with previous samples. Additionally, the study finds that genetic knowledge about health and illness seems to be the most accurate, whereas such knowledge about social categorisations and behaviours seems to be the most error-prone. In the current sample, being a female and having interest in genetics were positive predictors of genetic knowledge; surprisingly educational attainment was not a significant predictor. CONCLUSION: Compared with previous surveys, the current sample showed significantly better genetic knowledge. However, certain areas that relate to public understating still indicate rampant misperceptions.