Animal evolution: stiff or squishy notochord origins?
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Updated: Apr 20, 2026
09:38
Embryo Microinjection and Electroporation in the Chordate Ciona intestinalis
Published on: October 16, 2016
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Andreas Hejnol1, Christopher J Lowe1
1Sars International Centre of Marine Molecular Biology, University of Bergen, Norway; Hopkins Marine Station, Department of Biology, Stanford University, USA.
Current Biology : CB
|December 4, 2014
Abstract:
The notochord is considered an evolutionary novelty and one of the defining characters of chordates. A new study of an annelid challenges this view and proposes an earlier evolutionary origin in the most recent common ancestor of chordates and annelids.
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