Centro de Estudos do Ambiente e do Mar (CESAM), Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal.
Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, Utrecht University, Den Burg, Texel, The Netherlands.
J Anim Ecol. 2019 Aug;88(8):1226-1239. doi: 10.1111/1365-2656.12998. Epub 2019 May 13.
Identifying the factors shaping variation in parasite diversity among host species is crucial to understand wildlife diseases. Although micro- and macroparasites may exert different selective pressures on their hosts, studies investigating the determinants of parasite species richness in animals have rarely considered this divide. Here, we investigated the role of host life history and ecology in explaining the species richness of helminths (macroparasites) and haemosporidians (microparasites) in birds world-wide. We collated data from multiple global datasets on diverse bird traits (longevity, body mass, coloniality, migration distance/tendency, geographic range size and dietary and habitat breadths) and the species richness of their helminth and haemosporidian parasites. We tested predictors of helminth and haemosporidian parasite richness using phylogenetic generalized linear mixed models in a Bayesian framework. We found that, after controlling for research effort and host phylogeny, the richness of helminths, but not of haemosporidians, increased with host longevity, range size, migration distance and dietary breadth. Overall, these correlates were also important across different helminth groups (acanthocephalans, cestodes, nematodes and trematodes), and two additional ones (body mass, coloniality) emerged as important for cestodes and acanthocephalans. We propose that long life spans may promote the diversity of helminth parasite assemblages over evolutionary time, thus resulting in richer helminth faunas. Similarly, longer-distance migrations, larger ranges and broader dietary breadths are likely to lead to greater encounter rates and the accumulation of trophically transmitted helminths. In contrast, vector-borne haemosporidians may be influenced more by factors related to vector ecology than by the host traits included in the analyses. The lack of strong associations between haemosporidian species richness and host characteristics emphasizes the need to find appropriate traits to model the distribution and diversity of parasites with different environmental preferences in order to anticipate disease emergence risks associated with global change.
确定影响宿主物种间寄生虫多样性变化的因素对于了解野生动物疾病至关重要。尽管微寄生虫和大寄生虫可能对宿主施加不同的选择压力，但很少有研究调查动物寄生虫物种丰富度的决定因素时考虑到这种区别。在这里，我们研究了宿主生活史和生态学在解释全球鸟类的寄生虫（大寄生虫）和血液寄生虫（微寄生虫）物种丰富度中的作用。我们汇集了来自多个全球数据集的关于鸟类各种特征（寿命、体重、群居性、迁徙距离/倾向、地理范围大小以及饮食和栖息地范围）和寄生虫物种丰富度的信息，包括寄生虫的寿命、体重、群居性、迁徙距离和饮食范围。我们使用基于贝叶斯框架的系统发育广义线性混合模型来测试寄生虫丰富度的预测因子。我们发现，在控制研究努力和宿主系统发育后，寄生虫的丰富度（大寄生虫），而不是血液寄生虫的丰富度，随着宿主寿命、范围大小、迁徙距离和饮食范围的增加而增加。总的来说，这些相关性在不同的寄生虫组（棘头虫、绦虫、线虫和吸虫）中也很重要，另外两个（体重、群居性）对于绦虫和棘头虫也很重要。我们提出，较长的寿命可能会促进寄生虫组合在进化时间上的多样性，从而导致更丰富的寄生虫动物群。同样，远距离迁徙、更大的范围和更广泛的饮食范围可能会导致更大的接触率和营养传播寄生虫的积累。相比之下，通过媒介传播的血液寄生虫可能受到与媒介生态学相关的因素的影响比分析中包含的宿主特征更大。血液寄生虫物种丰富度与宿主特征之间缺乏强烈关联强调了需要找到适当的特征来模拟具有不同环境偏好的寄生虫的分布和多样性，以便预测与全球变化相关的疾病出现风险。
