Comparative transcriptomics, applied in an evolutionary context, has transformed the possibilities for studying phenotypic evolution in non-model taxa. We review recent discoveries about the development of novel, ecologically relevant phenotypes in hemipteran insects. These discoveries highlight the diverse genomic substrates of novelty: 'something old', when novelty results from changes in the regulation of existing genes or gene duplication; 'something new', wherein lineage-restricted genes contribute to the evolution of new phenotypes; and 'something borrowed', showcasing contributions of horizontal gene transfer to the evolution of novelty, including carotenoid synthesis (resulting in 'something red'). These findings show the power and flexibility of comparative transcriptomic approaches for expanding beyond the 'toolkit' model for the evolution of development. We conclude by raising questions about the relationship between new genes and new traits and outlining a research framework for answering them in Hemiptera.

中文翻译：

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旧的、新的、借来的、红色的：半翅目中与生态相关的新奇事物的起源。

在进化背景下应用的比较转录组学已经改变了研究非模型类群表型进化的可能性。我们回顾了关于半翅目昆虫中新的、生态相关的表型发展的最新发现。这些发现突出了新颖性的多种基因组底物：“旧的东西”，当新颖性来自现有基因或基因复制的调节变化时；“新事物”，其中谱系限制基因有助于新表型的进化；和“借来的东西”，展示了水平基因转移对新颖性进化的贡献，包括类胡萝卜素的合成（导致“红色的东西”）。这些发现显示了比较转录组学方法在扩展发展演变的“工具包”模型方面的力量和灵活性。最后，我们提出了关于新基因和新特征之间关系的问题，并概述了在半翅目中回答这些问题的研究框架。