FIGURE 1 in Review Renewed perspectives on the sedentary-pelagic last common bilaterian ancestor

FIGURE 1 The fossil records of the earliest sedentary and motile multicellular eukaryotes, metazoans and bilaterians. The first appearance of metazoan and bilaterian phyla (where records are present) is indicated by a genus name, a higher-level taxon acronym, and an age estimation (in millions of years). Several taxa with uncertain attribution are included to show diversity. Note that there is no evidence for active mobility of the muticellular eukaryotes over a very long period of time (see text for references and details). Abbrevations: Act = Acanthocephala; Ann = Annelida; Art = Arthropoda; Bil = Bilateria; Cha = Chaetognatha; Cte = Ctenophora; Cni = Cnidaria; Cho = Chordata; Deu = Deuterostomia; Ech = Echinodermata; Ecd = Ecdysozoa; Enp = Enteropneusta; Ent = Entoprocta; Gna = Gnathifera; Loph = Lophophorata; Lphz = Lophotrochozoa; Met = Metazoa; Mol = Mollusca; Pho = Phoronida; Por = Porifera; Pri = Priapulida; Pte = Pterobranchia; Tun = Tunicata. The controversial motile metazoans without evident bilaterian affinities are indicated by an asterisk. ARTWORK AND DESIGN BY TATIANA KORSHUNOVA