Urban and rural birds: genetic differentiation and the process of urbanisation.

城市地区通常被认为对生物多样性不太重要，保护工作转而针对农村栖息地。然而，城市栖息地被许多物种占据，其中一些物种的生活密度高于其传统的农村栖息地。尽管城市环境对野生动物具有潜在的重要性，但我们对城市生态学的了解却出奇地贫乏；此外，我们对一个物种从农村物种向城市物种过渡的过程知之甚少。这个项目的目的是调查一种典型的城市鸟类，黑鹂，是如何成为欧洲大部分城镇中如此熟悉的物种的。第一个目标将是利用历史记录详细追踪黑鸟在欧洲城市地区的殖民，从1820年德国最早的记录到现在，当时欧洲东北部和东部的城市仍在被殖民的过程中。第二个目标是沿着从最早的殖民化地区到目前正在发生城市占领的地区的样带，从成对的城市和农村样本中获得黑鹂的DNA样本；然后，我们将通过测量城市和农村栖息地黑鸟种群的遗传相似性来测试城市化过程的替代理论。这些分析的结果将使我们能够确定城市黑鹂是否：(i)仅仅是农村黑鹂，已经学会了利用城市环境；（ii）有多个起源，已经适应了当地农村人口的城市栖息地；（iii）有一个单一的起源，随后通过城市适应黑鹂在欧洲各地从一个城市扩散到另一个城市而扩散到其他城市地区。第三个目标是调查城市黑鸟与农村黑鸟是否在形态、饮食或蜱虫、虱子和血寄生虫的负担方面有所不同。将评估城市和农村人口之间的差异，以确定在不同栖息地对黑鸟施加的选择压力是否一致。

Urban areas are often regarded as being of little importance for biodiversity, conservation effort instead being directed at rural habitats. However, urban habitats are occupied by many species, some of which live at higher density than in their traditional rural habitat. Despite the potential importance of the urban environment for wildlife, our knowledge of urban ecology is surprisingly poor; furthermore, we know little of the process through which a species makes the transition from being a rural species to an urban one. The aim of this project is to investigate how a typical urban bird, the blackbird, has become such a familiar species in towns and cities across much of Europe. The first objective will be to use historical records to trace in detail the blackbird's colonisation of urban areas across Europe since the earliest records in Germany in 1820 to the present day, when cities in NE and E Europe are still in the process of being colonised. The second objective is to obtain DNA samples from blackbirds in paired urban and rural samples along a transect from the earliest areas of colonisation to areas where urban occupation is currently occurring; we will then test alternative theories for the process of urbanisation by measuring the genetic similarity of blackbird populations in urban and rural habitats. Results of these analyses will enable us to determine whether urban blackbirds: (i) are simply rural blackbirds that have learnt to exploit the urban environment, (ii) have multiple origins, having adapted to the urban habitat from local rural populations, (iii) have a single origin, with subsequent spread into other urban areas by the dispersal of urban-adapted blackbirds from one city to another across Europe. The third objective is to investigate whether urban blackbirds differ from rural ones in either their morphology, their diet or their burdens of ticks, lice and blood parasites. Differences between urban and rural populations will be assessed in order to determine whether the selective pressures operating on blackbirds differ consistently between habitats.