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181.
Martin Williams Eldon Eveleigh Glen Forbes Rosanna Lamb Lucas Roscoe Peter Silk 《Entomologia Experimentalis et Applicata》2019,167(8):755-762
This study examines the direct chemical defensive role of maltol, a previously identified secondary metabolite found in balsam fir, Abies balsamea (L.) Mill. (Pinaceae), that was detected during herbivory of spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae). Although used extensively in many industries, in addition to being found in multiple plant species, its functional role in plants remains unknown. The objectives of this study were to quantify the amount of free maltol and its potential conjugated form, maltol glucoside, in various foliage age classes and to evaluate whether constitutive foliage levels of maltol have an impact on spruce budworm fitness in maltol supplementation assays. Gas chromatography–mass spectrometry (GC‐MS) analysis of balsam fir foliage showed that maltol is produced in all foliage age classes tested; however, concentrations were significantly higher in older foliage. Liquid chromatography–mass spectrometry–mass spectrometry (LC‐MS‐MS) analysis showed that maltol also exists in balsam fir in its glucosylated form, a unique discovery in conifers. Similar to maltol, maltol glucoside is also present in current and 1‐year‐old balsam fir foliage and in significantly higher concentration in older foliage. We investigated the impact of maltol‐treated diet on spruce budworm fitness. Maltol additions that reflected constitutive foliage concentrations caused a significant reduction in larval development rate and pupal mass, whereas higher concentrations were required to cause significant mortality. These results suggest that maltol may be an important component of a direct defense strategy in balsam fir against spruce budworm herbivory. 相似文献
182.
Adoption and Kinship in Oceania 总被引:1,自引:0,他引:1
The frequency and form of adoption practices in Oceania recently have been cited as evidence that human behavior is inconsistent with predictions derived from sociobiological theory (Sahlins 1976). Ethnographic data reviewed here, however, suggest otherwise. In Oceania kinship is an important factor in the selection and treatment of adopted children as adoption occurs almost exclusively among close relatives. Natal children often ally against their adopted siblings over the division of their common parents' estate while adoptive parents themselves frequently apportion their land unequally among their natal and adopted children. These patterns and other data are consistent with predictions generated by a socio biological model of adoptive decisions. The model illustrates how kinship facilitates adoption as a means of modifying extreme family sizes, and how asymmetries in the degrees of relatedness between parents and their adopted and natal children provide the basis of differential treatment of them. Adoption in Oceania provides an example of a clearly cultural behavior which is consistent with socio biological predictions, and suggests that both culture and biology are relevant to an understanding of human behavior . [sociobiology, kinship, adoption, Oceania] 相似文献
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Ten polymorphic ovine microsatellites 总被引:2,自引:0,他引:2
189.
Comparative docking is based on experimentally determined structures of protein-protein complexes (templates), following the paradigm that proteins with similar sequences and/or structures form similar complexes. Modeling utilizing structure similarity of target monomers to template complexes significantly expands structural coverage of the interactome. Template-based docking by structure alignment can be performed for the entire structures or by aligning targets to the bound interfaces of the experimentally determined complexes. Systematic benchmarking of docking protocols based on full and interface structure alignment showed that both protocols perform similarly, with top 1 docking success rate 26%. However, in terms of the models' quality, the interface-based docking performed marginally better. The interface-based docking is preferable when one would suspect a significant conformational change in the full protein structure upon binding, for example, a rearrangement of the domains in multidomain proteins. Importantly, if the same structure is selected as the top template by both full and interface alignment, the docking success rate increases 2-fold for both top 1 and top 10 predictions. Matching structural annotations of the target and template proteins for template detection, as a computationally less expensive alternative to structural alignment, did not improve the docking performance. Sophisticated remote sequence homology detection added templates to the pool of those identified by structure-based alignment, suggesting that for practical docking, the combination of the structure alignment protocols and the remote sequence homology detection may be useful in order to avoid potential flaws in generation of the structural templates library. 相似文献
190.
Joan B. Silk Bailey R. House 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2016,371(1687)
In this paper, we consider three hypotheses to account for the evolution of the extraordinary capacity for large-scale cooperation and altruistic social preferences within human societies. One hypothesis is that human cooperation is built on the same evolutionary foundations as cooperation in other animal societies, and that fundamental elements of the social preferences that shape our species'' cooperative behaviour are also shared with other closely related primates. Another hypothesis is that selective pressures favouring cooperative breeding have shaped the capacity for cooperation and the development of social preferences, and produced a common set of behavioural dispositions and social preferences in cooperatively breeding primates and humans. The third hypothesis is that humans have evolved derived capacities for collaboration, group-level cooperation and altruistic social preferences that are linked to our capacity for culture. We draw on naturalistic data to assess differences in the form, scope and scale of cooperation between humans and other primates, experimental data to evaluate the nature of social preferences across primate species, and comparative analyses to evaluate the evolutionary origins of cooperative breeding and related forms of behaviour. 相似文献