Weider L J
Department of Biological Sciences, University of Windsor, N9B 3P4, Windsor, Ontario, Canada.
Oecologia. 1987 Sep;73(2):251-256. doi: 10.1007/BF00377515.
Laboratory life table experiments were conducted using nine clones of obligately parthenogenetic Daphnia pulex that were collected from a site in the Canadian low-arctic. Two of the nine clones were diploids, while the other seven clones were polyploids. Significant clonal differences in age at first reproduction, size at first reproduction, number of offspring in each of the first three broods, offsrring sizes for the first two broods, and intrinsic rates of natural increase were detected. Differences in life histories were evident between polyploids and diploids. Generally, polyploid clones reached maturity at later ages, matured at larger sizes, produced smaller broods, and larger offspring than the diploid clones. The data are discussed in reference to potential biotic (i.e. invertebrate predation) and abiotic factors (i.e. physicochemical gradients) that may influence life history variation in this clonal assemblage.
利用从加拿大低北极地区一个地点采集的9个专性孤雌生殖的蚤状溞克隆进行了实验室生命表实验。9个克隆中有2个是二倍体，另外7个克隆是多倍体。检测到在首次繁殖年龄、首次繁殖时的大小、前三窝中每窝的后代数量、前两窝的后代大小以及自然增长内在率方面存在显著的克隆差异。多倍体和二倍体之间的生活史差异明显。一般来说，多倍体克隆比二倍体克隆在更晚的年龄达到成熟，成熟时个体更大，产仔数更少，后代更大。结合可能影响该克隆群体生活史变异的潜在生物因素（即无脊椎动物捕食）和非生物因素（即物理化学梯度）对数据进行了讨论。
