Admixture and hybridization in North American cattails (Typha spp.)

每年，世界各地都有成百上千的物种被偶然或故意地迁移。 大多数物种无法在它们被引入的新环境中生存。 然而，由于不太清楚的原因，一些引进的物种表现得非常好，成为入侵物种，主宰新的栖息地，使本地物种灭绝，并花费数百万美元的根除计划。导致生物入侵的引入并不一定涉及特定地理区域的新物种：入侵也可能是由于引入本地物种的新遗传品种。 如果一个物种的种群在地理上分开的地区自然出现，例如加拿大的海洋省份和不列颠哥伦比亚省，就会发生这种情况。 在这个例子中，加拿大东部和西部的一个单一物种的种群已经彼此隔离了数千年，在此期间，它们进化成具有不同遗传谱系的东部和西部品种，尽管它们仍然被认为是单一物种的成员。 如果来自不列颠哥伦比亚省的个体找到了通往海洋省份的道路，它们可能会入侵新的栖息地。 最近引进的遗传谱系可以解释为什么香蒲（香蒲宽叶，香蒲angustifolia，和他们的杂交香蒲x glauca）正在成为越来越积极的湿地入侵者。 香蒲是湿地栖息地常见的大型植物，虽然它们原产于北美，但最近在加拿大和美国发现了引入的欧洲香蒲。 这意味着北美香蒲现在包括本地和引进的遗传谱系，欧洲谱系可能是香蒲入侵北美的原因。 我们将研究欧洲香蒲在多大程度上--无论是它们自己，还是与北美香蒲杂交--在加拿大湿地占主导地位。 通过使用香蒲作为一个模型系统，我们将产生重要的信息，可以帮助管理人员决定它将是多么重要，在未来的监测引进的“本地”物种，通过路线，如花园中心，因为这些“本地”物种可能实际上代表非本地的遗传谱系与潜在的入侵行为。 了解驱动生物入侵的过程是制定旨在最大限度地减少未来生物入侵的长期管理计划的必要前提。

Every year hundreds - possibly thousands - of species are either accidentally or intentionally moved around the world. Most species are unable to survive in the new environments to which they are introduced. However, for reasons that are not well understood, a few introduced species fare extraordinarily well and become invasive species that dominate new habitats, drive native species to extinction, and cost millions of dollars in eradication programs. Introductions that lead to biological invasions do not have to involve species that are new to a particular geographical area: invasions can also result from the introduction of new genetic varieties of a native species. This can happen if populations from a single species naturally occur in geographically separated areas, such as the Canadian maritime provinces and British Columbia. In this example, the eastern and western Canadian populations of a single species have been isolated from one another for thousands of years, during which time they evolved into eastern and western varieties with distinct genetic lineages, even though they are still considered members of a single species. If individuals from British Columia find their way to the maritime provinces, they could potentially become invasive in their new habitat. Recently introduced genetic lineages may explain why cattails (Typha latifolia, Typha angustifolia, and their hybrid Typha x glauca) are becoming increasingly aggressive wetland invaders. Cattails are large plants common to wetland habitats, and although they are native to North America, introduced European cattails have recently been identified in Canada and the USA. This means that North American cattails now comprise native and introduced genetic lineages, and the European lineages may be the cause of cattail invasions in North America. We will be looking at the extent to which European cattails - either on their own, or following interbreeding with North American cattails - are dominating Canadian wetlands. By using cattails as a model system, we will generate important information that can help managers to decide how important it will be in the future to monitor introductions of 'native' species through routes such as garden centres, because these 'native' species might actually represent non-native genetic lineages with the potential for invasive behaviour. Understanding the processes that drive biological invasions is a necessary precursor to the development of long-term management plans that aim to minimize future biological invasions.