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Similarity of the general designs of protochordates and invertebrates

Naturevolume 266pages533536 (1977) | Download Citation



THE protochordate amphioxus is clearly differentiated from the invertebrates by most taxonomic criteria1,2, and is recognised as the organism most closely resembling the early fish-like vertebrate progenitors3,4. Recently, however, Man-well5 has provided evidence that, with respect to enzyme variability, amphioxus resembles invertebrates rather than vertebrates. We report here that, in terms of gross sequence characteristics of DNA, amphioxus and two other protochordates, Ascidia mentula and Ciona intestinalis, more closely resemble the DNAs of the invertebrates, echinodermata and brachiopoda, rather than the DNA of higher vertebrates (craniata).

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  1. Medical Research Council Virology Unit, Institute of Virology, University of Glasgow, Church Street, Glasgow, UK

    • G. J. RUSSELL
    •  & J. H. SUBAK-SHARPE


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