Evolutionary Biology, Institue of Biology, Freie Universität Berlin, Berlin 14195, Germany.
Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08540.
Proc Natl Acad Sci U S A. 2024 Sep 17;121(38):e2402980121. doi: 10.1073/pnas.2402980121. Epub 2024 Sep 9.
More than 50% of all animal species are insects that undergo complete metamorphosis. The key innovation of these holometabolous insects is a pupal stage between the larva and adult when most structures are completely rebuilt. Why this extreme lifestyle evolved is unclear. Here, we test the hypothesis that a trade-off between growth and differentiation explains the evolution of this novelty. Using a comparative approach, we find that holometabolous insects grow much faster than hemimetabolous insects. Using a theoretical model, we then show how holometaboly evolves under a growth-differentiation trade-off and identify conditions under which such temporal decoupling of growth and differentiation is favored. Our work supports the notion that the holometabolous life history evolved to remove developmental constraints on fast growth, primarily under high mortality.
超过 50%的动物物种都是经历完全变态的昆虫。这些全变态昆虫的关键创新是幼虫和成虫之间存在一个蛹期，在此期间大多数结构会被完全重建。为什么这种极端的生活方式会进化还不清楚。在这里，我们检验了这样一种假设，即生长和分化之间的权衡解释了这种新颖性的进化。我们使用比较的方法，发现全变态昆虫的生长速度比半变态昆虫快得多。然后，我们使用一个理论模型表明，在生长-分化权衡下，全变态是如何进化的，并确定了这种生长和分化时间解耦受到青睐的条件。我们的工作支持了这样一种观点，即全变态的生活史是为了消除快速生长的发育限制而进化的，主要是在高死亡率的情况下。
