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Artificial seeds offer an important method to assay the bioactivity of natural and synthetic compounds against insect larvae that develop within the cotyledons of seeds. Here, the efficacy of artificial seeds as a mechanism to deliver bioactive compounds to larvae of the bruchid beetle, Callosobruchus maculatus, was compared to that of black-eyed beans that had been imbibed with the same bioactive compounds: malachite green or the methanolic extract of neem (Azadirachta indica). Females laid an equivalent number of eggs on control artificial seeds in comparison with black-eyed beans, although egg-to-adult survival on artificial seeds was reduced. Manipulation of the hardness of artificial seeds influenced female oviposition decisions, with more eggs laid on the harder seeds, although seed hardness had no effect on egg-to-adult survival. Incorporation of neem extract or malachite green into the artificial seeds resulted in 100 larval mortality, while larval mortality on seeds imbibed with neem extract or malachite green was between 50 and 70 . This suggests incorporation of toxins into artificial seeds, produces a more sensitive assay of compound toxicity in comparison with the method of imbibing seeds and offers a useful method to study of seed-arthropod interactions. © 2013 Springer Science+Business Media Dordrecht.

Animals that use materials to build nest structures have long since fascinated biologists and engineers alike. Avian nests are generally composed of collected materials brought together into a cup-like structure in which the bird sits to incubate eggs and, in many cases, it is where chicks are reared. Hence, the materials in a nest can be presumed to be loaded in compression, but relatively few studies have investigated the mechanical role of the nest elements and their position within the structure. However, recent studies on avian and primate nests have used engineering tests to quantify the structural properties of the nest elements to provide insight into how animals arrange the materials they collect and their mechanical role within the nest. In two studies, we deconstructed nests from Common Blackbirds (Turdus merula) and Bullfinches (Pyrrhula pyrrhula) into their component parts. We then used three-point bending tests to investigate regional variation in the structural properties of these elements within the nest. Results indicate that the birds use materials with different physical characteristics in various parts of the nest, thereby providing an indirect indication of nest-building behaviour in these species. We also used a novel cutting test, previously developed to measure the mechanical anisotropy of keratin, to investigate the mechanical behaviour of the mud-cup structure found in Common Blackbird and Song Thrush (Turdus philomelos) nests. This allowed us to determine whether these species utilise and arrange mineralised materials in a particular way to improve the toughness of their nests. The applicability of similar and other mechanical testing methods are discussed in relation to future investigations of the architecture and function of songbird nests.

Chemical characteristics of wood are used in this study for plant taxonomy classification based on the current Angiosperm Phylogeny Group classification (APG III System) for the division, class and subclass of woody plants. Infrared spectra contain information about the molecular structure and intermolecular interactions among the components in wood but the understanding of this information requires multivariate techniques for the analysis of highly dense datasets. This article is written with the purposes of specifying the chemical differences among taxonomic groups, and predicting the taxa of unknown samples with a mathematical model. Principal component analysis, t-test, stepwise discriminant analysis and linear discriminant analysis, were some of the chosen multivariate techniques. A procedure to determine the division, class, subclass and order of unknown samples was built with promising implications for future applications of Fourier Transform Infrared spectroscopy in wood taxonomy classification.

Fourier transform infrared (FTIR) spectroscopic data was used to classify wood samples from nine species within the Fagales and Malpighiales using a range of multivariate statistical methods. Taxonomic classification of the family Fagaceae and Betulaceae from Angiosperm Phylogenetic System Classification (APG II System) was successfully performed using supervised pattern recognition techniques. A methodology for wood sample discrimination was developed using both sapwood and heartwood samples. Ten and eight biomarkers emerged from the dataset to discriminate order and family, respectively. In the species studied FTIR in combination with multivariate analysis highlighted significant chemical differences in hemicelluloses, cellulose and guaiacyl (lignin) and shows promise as a suitable approach for wood sample classification.