“…Using this method, previous studies revealed the existence and diversity of the Hox genes in a variety of animals, including sponges (Seimiya et al, 1994;Degnan et al, 1995), cnidarians (Schierwater et al, 1991), flatworms (Bartels et al, 1993), annelids (Dick and Buss, 1994;Snow and Buss, 1994), chelicerate arthropods (Cartwright et al, 1993), and primitive groups of chordates and a hemichordate (Pendleton et al, 1993). These pieces of evidence suggest that the Hox system is widely conserved through all metazoans.…”