吸虱的生态位及其与小兽宿主的协同进化关系

目的 测定云南省主要小型哺乳动物(小兽)宿主体表寄生的优势吸虱的生态位指数及其与小兽宿主的协同进化关系。 方法 将云南省17县(市) 30种小兽宿主作为30级资源序列, 22种优势吸虱在小兽宿主体表的分布数量构成比作为其对各级资源的利用比例, 测定生态位宽度、生态位相似性比例指数及其生态位重叠指数。应用SPSS13.0统计软件对22种吸虱的生态位重叠指数原始数据矩阵进行系统聚类分析, 绘制树形聚类图。 结果 22种吸虱的生态位均较窄, 其中最宽的太平洋甲胁虱 (Hoplopleura pacifica) 仅为0.153 6。大多数吸虱生态位相似性比例指数较小(0.000 5～0.469 5)。对生态位重叠矩阵进行系统聚类分析, 当λ=5.5时, 将22种吸虱分为16个生态位重叠群。 结论 吸虱的宿主特异性高, 不同种类吸虱对宿主的选择性表现为明显的生态位分离。吸虱与小兽宿主协同进化程度较高。

Ecological Niches of Sucking Lice (Phthiraptera: Anoplura) and Their Coevolution Relationship with Small Mammal Hosts in Yunnan, China

OBJECTIVE: To investigate the ecological niches of sucking lice (Phthiraptera: Anoplura) on the body surface of small mammal hosts and the co-evolutionary relationship between lice and mammal hosts in Yunnan Province. METHOD: Thirty species of small mammals were captured and used as 30 resource sequences. The distribution and composition of the dominant 22 species of sucking lice on the body surface of the 30 species small mammal hosts were analyzed as the utilization proportion for each resource sequence. The niche breadth and proportional similarity were measured. SPSS 13.0 statistical software was used for analyzing the niche overlap matrix of sucking lice by hierarchical clustering analysis, and a dendrogram was made. RESULTS: The niche breadth was narrow for most species of sucking louse. Among the detected species, Hoplopleura pacifica showed the widest niche breadth, but only 0.1536. Indices of niche proportional similarity of most sucking lice were relatively small from 0.0005 to 0.4695. The 22 species of sucking lice were classified into 16 niche overlap groups, by lambda = 5.5, through a hierarchical clustering analysis for the niche overlaps, and the clustering process of most sucking lice was late. CONCLUSION: The sucking lice have a high specificity for hosts, of which different species show an apparent niche divergence on host selection. The results reveal a high coevolution between sucking lice and the mammal hosts.