Krasnov Boris R, Shenbrot Georgy I, Korallo-Vinarskaya Natalia P, Vinarski Maxim V, van der Mescht Luther, Warburton Elizabeth M, Khokhlova Irina S
Mitrani Department of Desert Ecology, Swiss Institute of Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Midreshet Ben-Gurion, Israel.
Laboratory of Arthropod-Borne Viral Infections, Omsk Research Institute of Natural Foci Infections, Omsk, Russian Federation.
Parasitol Res. 2019 Apr;118(4):1113-1125. doi: 10.1007/s00436-019-06255-4. Epub 2019 Feb 18.
We tested whether biogeographic patterns characteristic of species diversity and composition may also apply to community assembly by investigating geographic variation in the pattern (PSA) (aggregation versus segregation) and strength of species associations (SSA) in flea and mite communities harbored by small mammalian hosts in Western Siberia. We asked whether (a) there is a relationship between latitude and PSA or SSA and (b) similarities in PSA or SSA follow a distance decay pattern or if they are better explained by variation in environmental factors (altitude, amount of vegetation, precipitation, and air temperature). We used a sign of a co-occurrence metric (the C-score) as an indicator of PSA and its absolute standardized value as a measure of SSA. We analyzed data using logistic and linear models, generalized dissimilarity modeling (GDM), and a logistic version of the multiple regression on distance matrices (MRM). The majority of the C-scores of the observed presence/absence matrices indicated a tendency to species aggregation rather than segregation. No effect of latitude on PSA or SSA was found. The dissimilarity in PSA was affected by environmental dissimilarity in mite compound communities only. A relatively large proportion of the deviance of spatial variation in SSA was explained by the GDMs in infracommunities, but not component communities, and in only three (of seven) and two (of eight) host species of fleas and mites, respectively. The best predictors of dissimilarity in SSA in fleas differed between host species, whereas the same factor (precipitation) was the best predictor of dissimilarity in SSA in mites. We conclude that PSA and SSA in parasite communities rarely conform to biogeographic rules. However, when a biogeographic pattern is detected, its manifestation differs among hosts and between ectoparasite taxa.
通过研究西西伯利亚小型哺乳动物宿主所携带的跳蚤和螨虫群落中物种关联模式（PSA）（聚集与隔离）和强度（SSA）的地理变异，我们测试了物种多样性和组成的生物地理模式是否也适用于群落组装。我们探讨了以下问题：（a）纬度与PSA或SSA之间是否存在关系；（b）PSA或SSA的相似性是否遵循距离衰减模式，或者它们是否能更好地由环境因素（海拔、植被量、降水量和气温）的变化来解释。我们使用共现度量的符号（C分数）作为PSA的指标，其绝对标准化值作为SSA的度量。我们使用逻辑和线性模型、广义差异建模（GDM）以及距离矩阵多元回归的逻辑版本（MRM）来分析数据。观察到的存在/缺失矩阵的大多数C分数表明物种有聚集而非隔离的趋势。未发现纬度对PSA或SSA有影响。仅螨复合群落中PSA的差异受环境差异的影响。GDMs解释了亚群落而非组分群落中SSA空间变异偏差的相对较大比例，且仅分别解释了跳蚤和螨虫七个宿主物种中的三个以及八个宿主物种中的两个。跳蚤中SSA差异的最佳预测因子因宿主物种而异，而相同因素（降水量）是螨虫中SSA差异的最佳预测因子。我们得出结论，寄生虫群落中的PSA和SSA很少符合生物地理规则。然而，当检测到生物地理模式时，其表现在宿主之间以及体外寄生虫类群之间存在差异。
