恰加斯病是由原生动物寄生虫克氏锥虫引起的(恰加斯,1909).南美T.cruzi的主要载体之一是Triatomainfestans(Klug,1834).这种三角碱物种分布在一个巨大的纬度梯度上,居住在家里,包膜纤毛,和野生环境。其广泛的地理分布为研究环境梯度与种内形态变异之间的关系提供了极好的机会。在这项研究中,我们调查了六个生态区中T.infestans机翼大小和形状的变化。我们旨在解决以下问题:机翼大小和形状如何在区域范围内变化,形态变异是否沿着环境或纬度梯度遵循特定的模式,以及哪些环境因素可能导致翅膀变异?几何形态计量学方法应用于属于21个T.infestans种群的162只雌性的翅膀,13来自阿根廷(n=105),5来自玻利维亚(n=42),3来自巴拉圭(n=15)。对21个种群的机翼质心大小的比较显示出显着差异。典型变异分析(CVA)显示阿根廷种群之间机翼形状的显着差异,玻利维亚,巴拉圭,尽管有相当多的重叠,尤其是阿根廷人口。玻利维亚和巴拉圭群体的人口结构良好。进行了两项分析以评估机翼大小和形状之间的关联,地理和气候变量:大小的多元线性回归分析(MRA)和形状的偏最小二乘回归分析(PLS)。MRA显示出显著的一般模型拟合。六个与温度相关的变量,一个与降水相关的变量,纬度与机翼大小有显著关联。PLS分析显示机翼形状与纬度之间存在显着相关性,经度,温度相关,和降雨相关变量。T.infestans种群的机翼大小和形状因地理分布而异。我们的发现表明,地理和气候变量显着影响T.infestans机翼形态。
Chagas disease is caused by the protozoan parasite Trypanosoma cruzi (Chagas, 1909). One of the primary vectors of T. cruzi in South America is Triatoma infestans (Klug, 1834). This triatomine species is distributed across a huge latitudinal gradient, inhabiting domiciliary , peridomiciliary , and wild environments. Its wide geographic distribution provides an excellent opportunity to study the relationships between environmental gradients and intraspecific morphological variation. In this study, we investigated variations in
wing size and shape in T. infestans across six ecoregions. We aimed to address the following questions: How do
wing size and shape vary on a regional scale, does morphological variation follow specific patterns along an environmental or latitudinal gradient, and what environmental factors might contribute to
wing variation? Geometric morphometric methods were applied to the wings of 162 females belonging to 21 T. infestans populations, 13 from Argentina (n = 105), 5 from Bolivia (n = 42), and 3 from Paraguay (n = 15). A comparison of
wing centroid size across the 21 populations showed significant differences. Canonical Variate Analysis (CVA) revealed significant differences in wing shape between the populations from Argentina, Bolivia, and Paraguay, although there was a considerable overlap, especially among the Argentinian populations. Well-structured populations were observed for the Bolivian and Paraguayan groups. Two analyses were performed to assess the association between wing size and shape, geographic and climatic variables: multiple linear regression analysis (MRA) for size and Partial Least Squares (PLS) regression for shape. The MRA showed a significant general model fit. Six temperature-related variables, one precipitation-related variable, and the latitude showed significant associations with wing size. The PLS analysis revealed a significant correlation between wing shape with latitude, longitude, temperature-related, and rainfall-related variables.
Wing size and shape in T. infestans populations varied across geographic distribution. Our findings demonstrate that geographic and climatic variables significantly influence T. infestans wing morphology.