Bee sensitivity to a century of agricultural land-use change.

在过去的一个世纪里，由于全球人口的指数增长率，世界自然资源承受着巨大的压力。这导致了农业土地使用的显著增加，以及随之而来的“自然栖息地”的丧失，这一模式与生物多样性的严重丧失有关。昆虫传粉者，如大黄蜂的减少尤其令人关切，因为它们在维持花卉健康和多样性方面的作用至关重要，而且作为农业作物传粉者，它们拥有巨大的经济利益。因此，了解这些种群面临的威胁是当务之急。在这里，我们采取的方法是，要了解未来的威胁和解决方案，我们必须了解过去，为了准确预测未来的模式和物种面临的风险，我们必须更好地了解是什么导致了这些变化。不幸的是，有关昆虫传粉者丰度的档案数据很少能追溯到几十年前，而且大多数都是以随意的方式收集的。为了填补这一知识空白，我们将采取一种新的方法，使用DNA测序、形态和物候学(观察季节性活动的生活史数据)测量方法的组合，以及杀虫剂抗性的实验测试，我们将测试经历不同农业土地使用变化强度的种群是否表现出种群下降的特征和对这些新农业环境的适应(即支持因果关系)。在这里，我们将研究来自英国六个领先的自然历史博物馆的大量历史大黄蜂标本。这些标本中所代表的形态和基因组数据是决定种群规模、体型和遗传多样性在过去一个世纪中如何变化的关键。在恢复和分析古代DNA方面的最新进展，以及CT扫描分辨率的发展，将使我们能够获得前所未有的新见解。通过使用经历了不同数量的农业土地利用变化的地点的历史样本(例如，英国东部和西部的差异)，我们可以具体测试是否发生时间变化，而不是依赖于终点数据。人们普遍认为，大黄蜂受到与农业集约化相关的两个主要因素的威胁：花朵的损失导致营养资源的减少，以及农药暴露的增加。然而，据我们所知，这些相互作用的效果还没有经过实验测试。该项目还将进行受控实验室实验，以了解营养可获得性和农药暴露的变化如何影响蜂群生长和新蜂王和雄蜂的生产。

The world's natural resources have been placed under significant pressure over the past century, due to the exponential growth rate of the global human population. This has resulted in a significant increase in agricultural land-use and subsequent loss of 'natural habitats', a pattern associated with high losses in biodiversity. Declines of insect pollinators, such as bumblebees, are of particular concern as their role in maintaining floral health and diversity is vital, and as agricultural crop pollinators they possess large economic benefits. Understanding threats to these populations is therefore of high priority.Here we take the approach that to understand future threats and solutions we must understand the past, and that to accurately predict future patterns and risks to species, we must gain a better understanding of what is causing those changes. Unfortunately, archival data on insect pollinator abundance rarely goes back more than a couple of decades, and most have been collected in a haphazard way. To fill this knowledge gap we will take a novel approach in which, using a combination of DNA sequencing, morphological and phenological (life-history data looking at seasonal activity) measures, along with experimental test of pesticide resistance, we will test whether populations experiencing different agricultural land use change intensity show signatures of population declines and adaptation to these new agricultural environments (i.e. support for a causal relationship).Here, we will study a large collection of historical bumblebee specimens from six leading natural history museums across the UK. The morphological and genomic data represented in these specimens holds the key to determining how variation in population size, body shape and genetic diversity have changed over the last century.Recent advances in the recovery and analysis of ancient DNA, and developments in the resolution of CT scanning, will enable us to gain unprecedented and novel insights. By working with historical samples from locations that have undergone different amounts of agricultural land use change (for example differences between the east and west of UK) we can specifically test whether temporal changes occur, rather than relying on end point data.It is widely considered that bumblebees are threatened by two of the major factors associated with agricultural intensification: the loss of flowers leading to reduced nutritional resource, and increased exposure to pesticides. However, to our knowledge the interactive effects of these have not been experimentally tested. This project will also conduct a controlled laboratory experiment to understand how changes to nutritional availability and pesticide exposure impact on colony growth and the production of new queens and males.