Mechanisms to understand the basis of species invasiveness

了解物种入侵基础的机制

• 批准号: RGPIN-2016-04480
• 负责人: MacIsaac, Hugh
• 金额: $ 4.52万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=708760
• 关键词: Mechanisms; understand; basis; species; invasiveness

Biological invasions are a leading source of biodiversity change globally. Understanding the factors that contribute to invasion success at both the establishment-spread stage and impact stage are vital to reducing ecological, economic and health problems associated with introduction of nonindigenous species (NIS). Prior work has determined that some NIS that are introduced to and establish in a new ecosystem will have a greater ecological impact than do complementary native species at the same trophic level, possibly owing to prey naivety. It has proven very challenging to develop generalities to predict NIS impact, though recent work has focused on differences in functional responses - the feeding rate of an animal relative to food density. This work revealed generally higher feeding rates by invasive (i.e. high impact) NIS than their native analogues. However, the underlying basis for these feeding rate differences has not been addressed, nor has the generality of the pattern across different taxonomic groups. In this proposal I will conduct comparative feeding trials of NIS and native species from a broad array of environments - including terrestrial and aquatic environments - and trophic levels - predators versus herbivores - to test for differences in functional responses. Taxa selected will include broadly different taxonomic groups including beetles, mussels, fishes, ascidians and crabs, allowing us to examine the generality of feeding rate differences. Feeding trials of beetles will be videotaped, which will allow us to determine the species' behavioural repertoires (e.g. time budgets, attack rate). Functional responses are expressed through the interaction of an organism's physiology with its environment. When active, genes produce mRNAs, and up-regulation or down-regulation of these genes produces more or fewer of these molecules. Translation of these molecules into proteins enacts the responses (ie. feeding rate). We will apply transcriptomics using a candidate gene approach, whereby specific genes hypothesized to play a role in the efficiency of predation/herbivory, will be targeted. If invasiveness has a molecular basis, we expect that basic digestive enzymes (e.g. -amylases), metabolic genes (eg. ATPases), sensory genes (e.g. opsin genes), or muscle genes (e.g. tropomyosin) should be differentially expressed in invasive NIS versus native species. Our studies will also explore the importance of ambient temperature and life stages to these results.

生物入侵是全球生物多样性变化的主要来源。 了解在建立阶段和影响阶段有助于入侵成功的因素对于减少与引入非土著物种（NIS）相关的生态，经济和健康问题至关重要。先前的工作已经确定，在新的生态系统中引入并建立的一些NIS将产生比在同一营养水平上互补的本地物种具有更大的生态影响，这可能是由于猎物的天真性。 事实证明，开发通用性以预测NIS的影响非常具有挑战性，尽管最近的工作集中在功能反应的差异上 - 动物相对于食物密度相对于动物的进食率。这项工作通常显示出比其天然类似物的侵入性（即高影响力）更高的喂养率。 但是，这些喂养率差异的基本基础尚未得到解决，不同分类学组的模式的普遍性也没有解决。 在此提案中，我将对各种环境（包括陆地和水生环境以及营养水平 - 捕食者与食草动物）进行NIS和本地物种的比较进食试验，以测试功能反应的差异。 选定的分类单元将包括甲虫，贻贝，鱼类，海豚和螃蟹在内的广泛不同的分类群体，使我们能够检查喂养率差异的一般性。 甲虫的喂养试验将被录像，这将使我们能够确定该物种的行为曲目（例如时间预算，攻击率）。 功能反应是通过生物体与环境的相互作用来表达的。 当活性时，基因产生mRNA，这些基因的上调或下调会产生更多或更少的这些分子。这些分子转换为蛋白质颁布了反应（即进食率）。我们将使用候选基因方法应用转录组学，从而将假设的特定基因在捕食/草食性的效率中发挥作用。 如果侵入性具有分子基础，我们预计基本的消化酶（例如 - 淀粉酶），代谢基因（例如ATPases），感觉基因（例如Opsin基因）或肌肉基因（例如，肌动蛋白）应在侵入性NIS中差异化。我们的研究还将探讨环境温度和寿命阶段对这些结果的重要性。