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Updated: Oct 3, 2026

Early Metamorphic Insertion Technology for Insect Flight Behavior Monitoring
Published on: July 12, 2014
Endocrine insights into the evolution of metamorphosis in insects
James W Truman1, Lynn M Riddiford
1Department of Zoology, University of Washington, Seattle, Washington 98195-1800, USA. JWT@u.washington.edu
Abstract:
This review explores the roles of ecdysone and juvenile hormone (JH) in the evolution of complete metamorphosis and how metamorphosis, in turn, has impacted endocrine signaling. JH is a key player in the evolution of metamorphosis because it can act on embryos from more basal insect groups to suppress morphogenesis and cause premature differentiation, functions needed for transforming the transitional pronymphal stage of hemimetabolous insects into a functional larval stage. In the ancestral condition, imaginal-related growth is then delayed until JH finally disappears during the last larval instar. In the more derived groups of the Holometabola, selective tissues have escaped this JH suppression to form early-growing imaginal discs. We discuss how complete metamorphosis may have influenced the molecular aspects of both ecdysone and JH signaling.
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