The thermal plasticity of life-history traits receives wide attention in the recent biological literature. Of all the temperature-dependent traits studied, developmental rates of ectotherms are especially often addressed, and yet surprisingly little is known about embryonic responses to temperature, including changes in the thermal thresholds and thermal sensitivity during early development. Even postembryonic development of many cryptically living species is understood superficially at best. This study is the first to estimate the exact durations of developmental stages in the cowpea seed beetle C. maculatus from oviposition to adult emergence at five permissive constant temperatures from 20 to 32 °C. Early embryonic development was tracked and documented by means of destructive sampling and subsequent confocal imaging of fluorescently stained specimens. Late embryonic and early larval development was studied with the use of destructive sampling and light microscopy. Well-resolved temporal series based on thousands of embryos allowed precise timing of the following developmental events: formation of the blastoderm; formation, elongation, and retraction of the germ band; dorsal closure; the onset and completion of sclerotization of the cuticle; hatching, and penetration of the first-instar larva into the cowpea seed. Pupation and adult eclosion were observed directly through an incision in the seed coat. The thermal phenotype of C. maculatus was found to vary in the course of ontogeny and different stages scaled disproportionately with temperature, but pitfalls and caveats associated with analyses of relative durations of individual stages are also briefly discussed. Disproportionate changes in developmental durations with temperature may have important implications when study design requires a high degree of synchronization among experimental embryos or when the occurrence of particular stages in the field is of interest, as well as in any other cases when development times need to be estimated with precision. This work provides one of the first examples of integration of embryological techniques with ecophysiological concepts and will hopefully motivate similar projects in the future. While experiments with Drosophila continue to be the main source of information on animal development, knowledge on other model species is instrumental to building a broader picture of developmental phenomena.

中文翻译：

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the豆种子甲虫Callosobruchus maculatus（F.）的温度依赖性胚胎和胚后发育的阶段性解析。

生活史特征的热可塑性在最近的生物学文献中受到广泛关注。在研究的所有与温度相关的性状中，特别经常涉及到等温线的发育速率，但令人惊讶的是，人们对胚胎对温度的反应知之甚少，包括早期发育过程中热阈值和热敏感性的变化。甚至从表面上也可以理解许多秘密生物物种的胚胎后发育。这项研究是第一个估算the豆种子甲虫C. maculatus从产卵到成年出苗的确切阶段的持续时间，在五个允许的恒定温度20至32°C下进行。通过破坏性采样和随后的荧光染色标本的共聚焦成像，跟踪并记录了早期胚胎的发育。利用破坏性采样和光学显微镜研究了晚期胚胎和幼虫早期发育。很好的基于数千个胚胎的时间序列可以精确计时以下发育事件：胚盘的形成；生殖带的形成，伸长和收缩；背闭合 角质层硬化的开始和完成；孵化，并将初生幼虫渗透到the豆种子中。通过种皮上的切口直接观察化脓和成虫脱落。C的热表型。发现黄斑猴在个体发育过程中变化，并且不同阶段随温度成比例地缩放，但是还简要讨论了与分析各个阶段的相对持续时间有关的陷阱和警告。当研究设计要求实验胚胎之间高度同步时，或者当感兴趣的领域发生特定阶段时，以及在任何其他需要发育时间的情况下，发育持续时间随温度的不成比例的变化可能会产生重要影响。精确估计。这项工作提供了将胚胎学技术与生态生理学概念相结合的第一个实例，并有望在未来激发类似的项目。