Data from: Offspring development and life-history variation in a water flea depends upon clone-specific integration of genetic, non-genetic and environmental cues

1. Theory predicts that offspring developmental strategies involve the integration of genetic, non-genetic and environmental ‘cues’. But it is unclear how cue integration is achieved during development, and whether this pattern is general or genotype-specific. 2. In order to test this, we manipulated the maternal and offspring environments of three genetically distinct clones of the water flea Daphnia magna taken from different populations. We then quantified the effect that the genotype, maternal environment and the offspring environment had on the development and life-histories of the three different clones. 3. Mothers responded to the same maternal environments in different ways, resulting in clone-specific maternal effects on neonate size. Offspring responses to maternal cues varied according to the trait in question and were also clone-specific. The integration of these maternal effects during development was highly context-dependent in two clones but more consistent across environments in the third. 4. Genetic, non-genetic and environmental cues contributed to offspring phenotypic variation in all three clones, but there was no general pattern linking traits to specific cues. In fact, two clones used different combinations of cues at different points in development to achieve similar phenotypic outcomes. Thus different D. magna clones integrated different combinations of cues at different points in development. Our results highlight the importance of considering variation across development and show how genotypic variation and plasticity in developmental transitions help to generate phenotypic variation. 5. Our results support the hypothesis that phenotype determination involves the integration of genetic, non-genetic and environmental cues and demonstrates that the relative contributions of different cues is highly variable.

1. 理论预测，子代发育策略涉及遗传、非遗传与环境线索（cue）的整合。但目前学界尚未明确发育过程中线索整合的实现机制，也不清楚该模式究竟具有普适性，还是仅具有基因型（genotype）特异性。
2. 为验证该假说，我们对采集自不同种群的3个遗传背景各异的大型溞（Daphnia magna）克隆株的母体环境与子代环境进行了操控。随后，我们量化了基因型、母体环境以及子代环境对这3个不同克隆株的发育与生活史的影响。
3. 母体对相同的母体环境呈现出不同的响应模式，由此产生了克隆特异性的母体效应（maternal effects），进而影响新生幼体的体型。子代对母体线索的响应因所考察的性状而异，同样呈现克隆特异性。在2个克隆株中，发育过程中这些母体效应的整合高度依赖于具体情境；而第3个克隆株的整合模式则在不同环境中更为一致。
4. 在所有3个克隆株中，遗传、非遗传与环境线索均对子代表型变异（phenotypic variation）产生了贡献，但并未发现将性状与特定线索关联的通用模式。事实上，2个克隆株在发育的不同阶段采用了不同的线索组合，以实现相似的表型结果。由此可见，不同的大型溞克隆株在发育的不同阶段整合了不同的线索组合。本研究结果凸显了考虑发育过程中变异的重要性，并阐明了基因型变异与发育转变的可塑性如何促进表型变异的产生。
5. 本研究结果支持“表型决定涉及遗传、非遗传与环境线索整合”的假说，并证实不同线索的相对贡献度存在高度变异。