Collaborative Research: RUI: Measuring reciprocal natural selection in a contact zone in an obligate pollination mutualism

合作研究：RUI：在专性授粉互利共生中测量接触区的相互自然选择

• 批准号: 0918241
• 负责人: Christopher Smith
• 金额: $ 14.97万
• 依托单位: Willamette University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0918241&HistoricalAwards=false
• 关键词: Collaborative; Research; RUI; Measuring; reciprocal

This project addresses a fundamental question in evolutionary ecology; how does coevolution between plants and their insect pollinators create biodiversity. Joshua trees (Yucca brevifolia) are spiny, tree-like desert plants that are an iconic species of the American West. The trees are remarkable not only for their bizarre appearance, but also for their highly specialized and unusual means of pollination. They are pollinated exclusively by two species of Yucca moth in the genus Tegeticula; the moths, in turn, reproduce solely by laying their eggs in the flowers. This relationship between the Joshua tree and its pollinators is one of extreme interdependence; both the moth and the plant are entirely reliant upon one another for reproduction. The two species of Yucca moth that pollinate the Joshua tree differ in key features of their anatomy, particularly the size and shape of the female moth ovipositor, the organ used to inject their eggs into the Joshua tree flower. Recent work has shown that the particular trees on which these two moth species lay their eggs differ in features of their floral anatomy; the path through which the moth must insert her ovipositor is longer in trees that are pollinated by moths with a larger ovipositor, and shorter in flowers pollinated by moths with a shorter ovipositor. This anatomical match between the moths and the plants they pollinate likely reflects a history of coevolution, but this hypothesis has never been tested. This project will provide proof of concept that the hypothesis can be tested using reciprocal transplant experiments to quantify natural selection acting on the insects and the plants. In addition, the project will assess the feasibility of using molecular genetic techniques to reconstruct family relationships in the pollinators. The Joshua tree is a keystone species of the Mojave Desert ecosystem of the southwest USA, and is threatened by climate change with extinction over much of its range. Results from this project will inform local and federal conservation efforts to save Joshua trees through expansion of their range. This project will engage a number of undergraduates from a predominately undergraduate institution with research training in molecular genetics and evolutionary ecology.

该项目解决了进化生态学中的一个基本问题：植物和昆虫传粉者之间的共同进化如何创造生物多样性。 约书亚树（Yucca brevifolia）是一种多刺的树状沙漠植物，是美国西部的标志性物种。 这些树不仅因其奇异的外观而引人注目，而且还因其高度专业化和不寻常的授粉方式而引人注目。 它们完全由两种Tegeticula属的丝兰蛾授粉;反过来，蛾只通过在花中产卵繁殖。 约书亚树和它的传粉者之间的关系是一种极端相互依赖的关系;蛾和植物完全依赖彼此进行繁殖。 为约书亚树授粉的两种丝兰蛾在解剖学上的关键特征不同，特别是雌蛾产卵器的大小和形状，产卵器是用来将卵注入约书亚树花的器官。 最近的研究表明，这两种蛾产卵的特定树木在其花的解剖特征上有所不同;蛾必须插入产卵器的路径在由具有较大产卵器的蛾授粉的树木中较长，而在由具有较短产卵器的蛾授粉的花朵中较短。 飞蛾和它们授粉的植物之间的解剖学匹配可能反映了共同进化的历史，但这一假设从未得到过验证。 该项目将提供概念证明，该假设可以使用相互移植实验来量化作用于昆虫和植物的自然选择。 此外，该项目将评估利用分子遗传技术重建传粉者家庭关系的可行性。 约书亚树是美国西南部莫哈韦沙漠生态系统的关键物种，受到气候变化的威胁，其大部分范围都在灭绝。 该项目的结果将为地方和联邦保护工作提供信息，通过扩大树木的范围来拯救约书亚树。 这个项目将吸引一些本科生从一个占主导地位的本科院校的分子遗传学和进化生态学的研究训练。