The Adelgidae form a small clade of insects within the Aphidoidea (Hemiptera) that includes some of the most destructive introduced pest species threatening North American forest ecosystems. Despite their importance, little is known about their evolutionary history and their taxonomy remains unresolved. Adelgids are cyclically parthenogenetic and exhibit multigeneration complex life cycles. They can be holocyclic, with a sexual generation and host alternation, or anholocyclic, entirely asexual and without host alternation. We discuss adelgid behavior and ecology, emphasizing plant-insect interactions, and we explore ways that the biogeographic history of their host plants may have affected adelgid phylogeny and evolution of adelgid life cycles. Finally, we highlight several areas in which additional research into speciation, population genetics, multitrophic interactions, and life-history evolution would improve our understanding of adelgid biology and evolution.

中文翻译：

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蜘蛛科的生物学和进化。

蚜科（Adelgidae）在蚜虫（半翅目）内形成了一个小的昆虫进化枝，其中包括一些破坏性最强的有害生物物种，威胁了北美森林生态系统。尽管它们很重要，但对其进化史知之甚少，其分类学仍未解决。Adelgids具有周期性孤雌生殖作用，并表现出多代复杂生命周期。它们可以是具有性世代和寄主交替的完整环，也可以是完全无性无寄主交替的无环。我们讨论了adelgid的行为和生态，强调了植物与昆虫之间的相互作用，并探讨了其寄主植物的生物地理历史可能影响adelgid的系统发育和adelgid生命周期演变的方式。最后，我们重点介绍几个领域，其中包括物种形成，种群遗传学，