Ecology and evolution of floral scents in the perfume flowers

这种所谓的“香水花”产生的花香是雄性兰花蜜蜂独有的气味，用来在求偶展示时向雌性表明它们的健康状况/身份(物种)。最近的研究表明，这些植物中花香的进化是由其优黄碱传粉者先前存在的感觉偏差形成的。然而，对这一点的实验支持仍然存在争议。20世纪60年代至90年代，人们对雄性兰花蜜蜂授粉植物花香的化学成分以及它们在吸引传粉者中的作用进行了深入的研究。然而，目前的估计表明，传粉者的身份(在特定水平上)和所有香花物种中超过80%的化学成分仍然未知。显然，关于传粉者和花香化学的有限信息，所涉及的植物分类群的未解决的系统发育，以及对真花授粉者的感觉/行为偏见的初步了解，使得更全面地了解控制香料花与其传粉者之间相互作用的生态和进化机制是困难的。在目前的提案中，我们旨在了解花卉香水的生态和进化意义。为此，我们将使用不同学科的现代技术，如化学生态学、传粉生物学、行为生态学、昆虫生理学和分子系统学。目前有关传粉者和花卉香水化学成分的知识将在文献的系统回顾中汇编。为了增加互动的知识，花卉参观者将直接聚集在花卉上。花香样本将被收集并用于生物分析和化学分析。授粉者的感觉(嗅觉)偏差将使用触电(EAG)分析进行调查，并将在野外对雄性兰花蜜蜂进行行为生物分析。基于GenBank中提供的分子数据，将重建具有香水花卉的物种及其传粉者的系统发育关系。通过这种综合的方法，我们将检验香水花整体花香属性宏观进化的基本假设。鉴于其多学科方法，该项目将有来自不同机构的经验丰富的研究人员组成的团队参与，促进加强已有的、成功的国际合作和学生交流。这个项目将帮助我们对涉及雄兰蜂和香水花的特殊相互作用的自然历史的基本方面做出贡献，并理解花香在这种互惠关系的生态和进化中的重要性。

Flowers of the so-called “perfume flowers” produce floral scent that is collected exclusively by male orchid bees (Euglossini: Apidae) and used to signal their fitness/identity (species) to females during courtship display. Recent studies suggest that the evolution of floral scents in these plants is shaped by preexisting sensory biases of their euglossine pollinators. However, experimental support for this is still controversial. The chemical composition of floral scents in plants pollinated by male orchid bees, as well as their role in attracting pollinators, was intensively studied between the 1960s and 1990s. Nevertheless, current estimates suggest that pollinator identity (at the specific level) and the chemical composition of more than 80 % of all species with perfume flowers remain unknown. Obviously, the limited information about pollinators and floral scent chemistry, the unresolved phylogeny of the plant taxa involved and an incipient understanding of the sensory/behavioral biases of euglossine pollinators, make it difficult to have a more comprehensive understanding of the ecological and evolutionary mechanisms that govern the interactions between perfume flowers and their pollinators. In the present proposal, we aim at understanding the ecological and evolutionary meaning of floral perfumes. For this, we will use modern techniques from various disciplines, such as chemical ecology, pollination biology, behavioral ecology, insect physiology and molecular phylogeny. Current knowledge about pollinators and about the chemical composition of floral perfumes will be compiled in a systematic review of the literature. In order to add to the knowledge of the interactions, floral visitors will be collected directly on flowers. The floral scent samples will be collected and used for bioassays and chemical analyses. Sensory (olfactory) biases of pollinators will be investigated using electroantenographic (EAG) analyzes, and behavioral bioassays in the field will be performed with male orchid bees. The phylogenetic relationships of species with perfume flowers, as well as their pollinators will be reconstructed based on molecular data available in GenBank. With this integrative approach, we will test fundamental hypotheses about the macroevolution of floral attributes in perfume flowers as a whole. In view of its multidisciplinary approach, this project will involve an experienced team of researchers from different institutions, promoting the strengthening of well-established and successful international cooperation and the exchange of students. This project will help us to both contribute to the scanty knowledge on basic aspects of the natural history of the specialized interaction involving male orchid bees and perfume flowers and understand the significance of floral scents in the ecology and evolution of this mutualism.