Translocation Experiments: Bosmina Responses to Copepod Predation
Translocation Experiments: Bosmina Responses to Copepod Predation
复制标题
易位实验：Bosmina 对桡足类捕食的反应
DOI：
10.2307/1938465
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发表时间：
1987
期刊：
影响因子：
4.8
通讯作者：
W. Kerfoot
中科院分区：
文献类型：
--
作者：
W. Kerfoot
对小型枝角类 Bosmina longirostris 的区域调查揭示了 com?复杂的形态模式。身体大小和形状差异很大，其中后细触角和前触角的差异最明显。一些湖泊具有短特征克隆，大多数具有中间特征，而少数湖泊则具有非常长特征的克隆。形态相似的邻近湖泊可能有短特征或长特征的克隆。对地理模式的可能解释包括：（1）最初的殖民事件，（2）com？殖民后的竞争性释放，（3）以前隔离的繁殖种群之间的杂交，以及（4）来自常驻捕食者，特别是杂食性桡足类动物的自然选择。田间易位实验证明了 Epischura 捕食对于决定长特征克隆成功的重要性。猎物风险取决于大小和形状，适应性很大程度上取决于早期龄期的存活率差异。与较长特征相关的适应性增加在几个层面上都很明显：（1）在从休眠卵进行克隆招募期间，（2）在易位种群的成功中，以及（3）作为暴露的猎物种群内的发育反应。在 Epischura 的长期投资中，短期股票的特征长度增加了几个标准差。尽管触角长度和卵长度也显示出显着增加，但毛长度显示出最大的反应。在Epischura lacustris-Bosmina longirostris相互作用期间，反应显然是两种不同现象的联合效应：选择性反应（由于死亡率不同）和化学诱导（发育可塑性）。宏观和触角反应伴随着变异系数的显着下降。
Regional surveys of the small cladoceran Bosmina longirostris reveal a com? plex morphological pattern. Body size and shape vary greatly, with the most pronounced differences found in the posterior mucrones and anterior antennules. Some lakes have short-featured clones, most have intermediates, while a few have very long-featured clones. Neighboring lakes of similar morphometry can have short- or long-featured clones. Possible explanations for the geographic patterns include: (1) initial colonization events, (2) com? petitive release following colonization, (3) hybridization between formerly isolated breeding stocks, and (4) natural selection from resident predators, particularly omnivorous copepods. Field translocation experiments demonstrated the importance of Epischura predation in determining the success of long-featured clones. Prey risk was both size- and shape- dependent, with fitness determined largely through the differential survivorship of early instars. Increased fitness associated with longer features was evident at several levels: (1) during clonal recruitment from resting eggs, (2) in the success of translocated stocks, and (3) as developmental responses within exposed prey populations. In long-term exposures to Epischura, feature lengths of short-featured stocks increased by several standard deviations. Mucro length showed the greatest response, although an- tennule lengths and egg lengths also showed significant increases. During the Epischura lacustris-Bosmina longirostris interaction, responses were clearly the joint effect of two separate phenomena: selective responses (due to differential mortality) and chemical in- duction (developmental plasticity). Mucro and antennule responses were accompanied by significant declines in coefficients of variation.