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Updated: Jul 21, 2025

Ex Vivo Culture of Pharyngeal Arches to Study Heart and Muscle Progenitors and Their Niche
Published on: July 20, 2015
Comment on "Ultrastructure reveals ancestral vertebrate pharyngeal skeleton in yunnanozoans"
Kaiyue He1, Jianni Liu1, Jian Han1
1Shaanxi Key Laboratory of Early Life and Environments, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University (NWU), Xi'an 710069, P. R. China.
Abstract:
Tian et al. (Research Articles, 8 July 2022, abm2708) hypothesized that yunnanozoans are stem-group vertebrates on the basis of "cellular cartilage", "fibrillin microfibers", and "subchordal rod" associated with the branchial arches of yunnanozoans. However, we reject the presence of cellular cartilage, fibrillin, and the phylogenetic proposal of vertebrate affinities based on ultrastructure and morphology of yunnanozoans from more than 8000 specimens.
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