Fig. 6From: What is Xenoturbella?Different scenarios for the evolution of morphology and larva of Xenoturbella. a, b Phylogenetic trees showing Xenacoelomorpha as an early-branching bilaterian. c, d Phylogenetic trees showing Xenacoelomorpha as a deuterostome. Black circles show gain and black crosses show loss of adult organs (e.g. coeloms and anus). White circles show gain and white crosses show loss of feeding planktotrophic larvaBack to article page