Evidence of Evolutionary Close Relationship between Echinoderms and Vertebrates

The present author has been studying the biochemical systematics of echinoids and asteroids of echinoderms by using some biochemical methods such as allozyme analysis, immunological assay, enzyme kinetic study, and comparison of amino acid composition (Matsuoka, 1980, 1986, 1987, 1992; Matsuoka et al., 1983; Matsuoka and Suzuki, 1989; Matsuoka and Hatanaka, 1991, etc.). Echinoderms are representative of sea-shore animals. Echinoderms consist of five classes: sea-lily, sea-cucumber, starfish, sea-urchin and brittle-star (Fig. 1). The author reported the phylogeny of four classes of echinoderms by the enzyme kinetic study of glucose-6-phospahte dehydrogenase (G6PD) (Matsuoka, 1992). Of these five echinodermes, echinoids have been widely used in various biological fields: developmental biology, biochemistry, physiology and ecology. These five classes are distinct groups in morphological viewpoint. The pentamery is the common body system in echinoderms. From some viewpoint, it has been considered that echinoderms are evolutionary close related to vertebrates. In this nimi-review, I review about the molecular and nonmolecular evidence of evolutionary close relationship between echinoderms and vertebrates.