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Updated: Jun 2, 2026

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
Evolution of motor innervation to vertebrate fins and limbs
Yasunori Murakami1, Mikiko Tanaka
1Department of Biology, Faculty of Science, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime, Japan. bothrops@sci.ehime-u.ac.jp
Abstract:
The evolution and diversification of vertebrate behaviors associated with locomotion depend highly on the functional transformation of paired appendages. Although the evolution of fins into limbs has long been a focus of interest to scientists, the evolution of neural control during this transition has not received much attention. Recent studies have provided significant progress in the understanding of the genetic and developmental bases of the evolution of fin/limb motor circuitry in vertebrates. Here we compare the organization of the motor neurons in the spinal cord of various vertebrates. We also discuss recent advances in our understanding of these events and how they can provide a mechanistic explanation for the evolution of fin/limb motor circuitry in vertebrates.
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