Milner Centre for Evolution, University of Bath, Bath, United Kingdom.
Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), Seville, Spain.
PLoS One. 2020 Aug 17;15(8):e0237369. doi: 10.1371/journal.pone.0237369. eCollection 2020.
Do islands harbour less diverse disease communities than mainland? The island biogeography theory predicts more diverse communities on mainland than on islands due to more niches, more diverse habitats and availability of greater range of hosts. We compared bacteria prevalences of Campylobacter, Chlamydia and Salmonella in cloacal samples of a small shorebird, the Kentish plover (Charadrius alexandrinus) between two island populations of Macaronesia and two mainland locations in the Iberian Peninsula. Bacteria were found in all populations but, contrary to the expectations, prevalences did not differ between islands and mainland. Females had higher prevalences than males for Salmonella and when three bacteria genera were pooled together. Bacteria infection was unrelated to bird's body condition but females from mainland were heavier than males and birds from mainland were heavier than those from islands. Abiotic variables consistent throughout breeding sites, like high salinity that is known to inhibit bacteria growth, could explain the lack of differences in the bacteria prevalence between areas. We argue about the possible drivers and implications of sex differences in bacteria prevalence in Kentish plovers.
岛屿上的疾病群落是否比大陆上的疾病群落多样性更低？岛屿生物地理学理论预测，由于更多的小生境、更多样的栖息地和更大范围的宿主，大陆上的生物群落会更加多样化。我们比较了马卡罗尼西亚两个岛屿种群和伊比利亚半岛两个大陆地点的小滨鸟（Kentish plover，Charadrius alexandrinus）泄殖腔样本中的弯曲杆菌、衣原体和沙门氏菌的细菌流行率。所有种群中都发现了细菌，但与预期相反，岛屿和大陆之间的流行率没有差异。与沙门氏菌相比，雌性的流行率高于雄性，而当将三种细菌属合并在一起时，雌性的流行率则更高。细菌感染与鸟类的身体状况无关，但来自大陆的雌性比雄性重，来自大陆的鸟类比来自岛屿的鸟类重。在繁殖地点普遍存在的非生物变量，如已知抑制细菌生长的高盐度，可能解释了不同地区之间细菌流行率没有差异的原因。我们对肯特滨鸟中细菌流行率的性别差异的可能驱动因素和影响进行了讨论。
