Department of Behavioural Ecology, Bielefeld University, Konsequenz 45, 33619, Bielefeld, Germany.
Centre of New Technologies, University of Warsaw, Banacha Street 2C, 02-097, Warsaw, Poland.
Sci Rep. 2022 Apr 27;12(1):6872. doi: 10.1038/s41598-022-10734-7.
Urbanisation is a major anthropogenic perturbation presenting novel ecological and evolutionary challenges to wild populations. Symbiotic microorganisms residing in the gastrointestinal tracts (gut) of vertebrates have mutual connections with host physiology and respond quickly to environmental alterations. However, the impact of anthropogenic changes and urbanisation on the gut microbiota remains poorly understood, especially in early development. To address this knowledge gap, we characterised the gut microbiota of juvenile great tits (Parus major) reared in artificial nestboxes and in natural cavities in an urban mosaic, employing two distinct frameworks characterising the urban space. Microbial diversity was influenced by cavity type. Alpha diversity was affected by the amount of impervious surface surrounding the breeding location, and positively correlated with tree cover density. Community composition differed between urban and rural sites: these alterations covaried with sound pollution and distance to the city centre. Overall, the microbial communities reflect and are possibly influenced by the heterogeneous environmental modifications that are typical of the urban space. Strikingly, the choice of framework and environmental variables characterising the urban space can influence the outcomes of such ecological studies. Our results open new perspectives to investigate the impact of microbial symbionts on the adaptive capacity of their hosts.
城市化是一种主要的人为干扰，给野生动物种群带来了新的生态和进化挑战。栖息在脊椎动物胃肠道（肠道）中的共生微生物与宿主生理学相互关联，并能迅速对环境变化做出反应。然而，人为变化和城市化对肠道微生物群的影响仍知之甚少，尤其是在早期发育阶段。为了解决这一知识空白，我们采用了两种不同的框架来描述人工巢箱和城市镶嵌体中自然洞穴中饲养的幼年大山雀（Parus major）的肠道微生物群，这些框架用于描述城市空间。微生物多样性受洞穴类型的影响。α多样性受繁殖地点周围不透水面的数量影响，并与树木覆盖密度呈正相关。城市和农村地区的群落组成不同：这些变化与噪音污染和与市中心的距离有关。总的来说，微生物群落反映并可能受到城市空间中典型的异质环境变化的影响。引人注目的是，用于描述城市空间的框架和环境变量的选择会影响此类生态研究的结果。我们的研究结果为研究微生物共生体对宿主适应能力的影响开辟了新的视角。
