The spatial organization of digestion, which corresponds to the steps by which the ingested food is hydrolyzed in the different regions of the gut, was described in insects from the major insect orders. The data showed that the overall pattern of digestion depends more on the insect phylogeny than on the insect feeding habits. Based on this, basic digestive patterns were recognized and were proposed to represent the major ancestors from which the different orders evolved. The putative ancestors chosen to represent different points in the evolution from basal Neoptera to more derived orders were: Neoptera, Hemiptera, Hymenoptera-Panorpoidea (Diptera-Lepidoptera), Lepidoptera, Cyclorrhapha. This review updates the physiological data supporting the putative midgut basic patterns by discussing available data on insects pertaining to different taxa and details the evolutionary trends of midgut function among the major insect orders. Furthermore, by using recent genomic and transcriptome data, this review discusses the few insects for which the spatial organization of midgut absorption is known.

中文翻译：

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主要昆虫目消化吸收的进化趋势。


消化的空间组织，对应于摄入的食物在肠道不同区域水解的步骤，在主要昆虫目的昆虫中得到了描述。数据显示，消化的总体模式更多地取决于昆虫的系统发育，而不是昆虫的食性。在此基础上，人们认识到了基本的消化模式，并提出代表不同目进化而来的主要祖先。选择代表从基础新翅目到更衍生目的进化中不同点的推定祖先是：新翅目、半翅目、膜翅目-全翅目（双翅目-鳞翅目）、鳞翅目、圆翅目。本综述通过讨论不同类群昆虫的现有数据，更新了支持假定中肠基本模式的生理数据，并详细介绍了主要昆虫目中肠功能的进化趋势。此外，通过使用最新的基因组和转录组数据，本综述讨论了已知中肠吸收空间组织的少数昆虫。