Extinction risks and invasiveness in the British flora

植物是地球上生命的基础，提供多种生态系统服务。然而，关于灭绝风险的潜在生物学的科学研究正在逐步发展，而且主要集中在脊椎动物上。到目前为止，IUCN红色名录提供了最广泛使用和众所周知的评估灭绝风险的系统。最初，它并不打算设定保护优先事项，但在实践中，它往往直接进入这一过程。PI最近的研究表明，南非开普植物群的灭绝和物种形成过程是相互联系的-似乎最脆弱的物种往往是最年轻的物种（2）。这项研究重新引发了关于如何最好地使用IUCN红色名录的辩论：事实上，年轻的物种可能会出现灭绝的高风险，仅仅是因为它们的种群还没有时间增长和传播（2，3）。然而，也有可能一些植物物种从一开始就注定要灭绝。至关重要的是，Savolainen及其同事发现，最脆弱的植物物种仍然以更快的速度走向灭绝，但令人惊讶的是，独立于人类的影响。 外来入侵植物的入侵是对生态系统的另一个主要威胁。事实上，全世界有多达50万种物种被归类为“入侵性外星人”，每年造成的损失超过1万亿欧元。到目前为止，还不可能预测引进的物种是否会成为入侵者，也不清楚某些特征是否会促进入侵。PI最近在亚热带群岛（亚速尔群岛）的研究表明，当该地区没有密切相关的物种时，引入的植物物种很可能成为入侵物种（5）。利用系统发育信息，一些进化相关性的措施变成了一个可靠的预测入侵。此外，通过对不同地理尺度的分析，Savolainen及其同事认为，敌人的释放在亚速尔群岛的生物入侵中起着重要作用（5）。 尽管英国植物在分类学、地理学和生态学方面是世界上最著名的，但令人惊讶的是，它们灭绝风险的原因以及“外来物种”（目前英国的本土物种数量超过本土物种）的威胁都没有得到充分研究。以下方法由PI在亚热带地区开发，并建立在主机上的初步系统发育数据，我们将填补这一知识空白-旨在确定在英国植物群的入侵和预测的相关性。毫无疑问，英国和亚热带地区之间的比较也将证明是相关的。

Plants are the basis of life on earth and provide multiple ecosystem services. However, scientific research on the underlying biology of extinction risks is developing piecemeal, and has mostly focused on vertebrates. To date, the IUCN Red List provides the most widely used and well-known system for assessing extinction risks (1). Initially, it was not intended to set conservation priorities, but in practice it often feeds directly into this process. Recent research by the PI of this proposal showed that the processes of extinction and speciation are linked in the Cape flora of South Africa - seemingly the most vulnerable species are often the youngest (2). This research revived debates about how best to employ IUCN Red Lists: indeed, young species may appear at high risk of extinction simply because their populations have not yet had time to grow and spread (2, 3). However, it is also possible that some plant species might be doomed to extinction from their very inception. Critically, Savolainen and co-workers found that the most vulnerable plant species are nonetheless marching towards extinction at a more rapid pace, but surprisingly, independently from human impact (2). Encroachment by invasive alien plants is another major source of threat to ecosystems. Indeed, up to half a million species are classified as 'invasive aliens' worldwide, causing costs of over 1 trillion euros per year (4). So far, it has not been possible to predict whether an introduced species will become invasive, and it is unclear whether certain traits promote invasiveness. Recent research by the PI in a subtropical archipelago (Azores) showed that introduced plant species are likely to become invasive when there are no closely related species in the area (5). Using phylogenetic information, some measures of evolutionary relatedness turned out to a reliable predictor of invasiveness. Also, using analyses at different geographic scales, Savolainen and co-workers argued that enemy release plays an important role in biological invasions in the Azores (5). Although British plants are by far some of the best-known anywhere in the world in terms of taxonomy, geography and ecology - astoundingly, the causes of their extinction risks as well as threats by 'alien taxa' (currently outnumbering native species in the UK) are understudied. Following methodologies developed by the PI in subtropical areas, and building on preliminary phylogenetic data available at the host, we will fill this knowledge gap - aiming to identify correlates of extinctions and predictors of invasions in the British flora. Undoubtedly comparisons between the UK and the subtropics will also prove pertinent.