• Alberto Stolfi
  • Federico D. BrownEmail author


Tunicates are a group of marine filter-feeding animals that have been traditionally divided into three classes: (1) Appendicularia, also known as larvaceans because their free-swimming and pelagic adult stage resembles a larva; (2) Thaliacea, which includes three orders of free-swimming and pelagic adult forms with complex life cycles (Salpida, Pyrosomida, and Doliolida); and (3) Ascidiacea, colloquially referred to as sea squirts, which is comprised of diverse sessile solitary and colonial species and includes some of the most extensively studied tunicates. It was mainly the ascidians that served as the inspiration for seminal studies in developmental biology and evolution conducted last century by British zoologist and prolific writer N. J. Berrill, whose quote appears above


Neural Tube Neural Plate Notochord Cell Larval Muscle Colonial Ascidian 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Many thanks to Andreas Wanninger and Ivan Dias for comments on the manuscript and to Florian Razy-Krajka for thoughtful discussions. Thanks to Leda Restrepo, Gabriela Agurto, Joanna Greer, and Paul Caiger for contributing with some figures. We would also like to thank all the authors who have granted us permission to modify and adapt figures from their excellent papers. This work was supported by an “Apoio aos Novos Docentes” Grant from Universidade de São Paulo, an Assistant Professor Grant from Universidad de los Andes and a Prometeo Research Award from the Secretaría Nacional de Ciencia, Tecnología e Innovación (Senescyt-Ecuador) to F. D. B., and by a National Science Foundation Postdoctoral Research Fellowship (under grant NSF-1161835) to A. S.


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© Springer-Verlag Wien 2015

Authors and Affiliations

  1. 1.Department of BiologyCenter for Developmental Genetics, New York UniversityNew YorkUSA
  2. 2.EvoDevo Laboratory, Departamento de ZoologiaInstituto de Biociências, Universidade de São PauloSão PauloBrazil
  3. 3.Evolutionary Developmental Biology Laboratory, Department of Biological SciencesUniversidad de los AndesBogotáColombia
  4. 4.Centro Nacional de Acuicultura e Investigaciones Marinas (CENAIM)Escuela Superior Politécnica del Litoral (ESPOL)San PedroEcuador

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