Regeneration in spiralians: evolutionary patterns and developmental processes
Published: 15 January 2015
Alexandra E. Bely*,1, Eduardo E. Zattara1,2 and James M. Sikes3
1Department of Biology, University of Maryland, College Park, Maryland, USA2Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington DC, USA and 3Department of Biology, University of San Francisco, San Francisco, California, USA
Animals differ markedly in their ability to regenerate, yet still little is known about how regeneration evolves. In recent years, important advances have been made in our understanding of animal phylogeny and these provide new insights into the phylogenetic distribution of regeneration. The developmental basis of regeneration is also being investigated in an increasing number of groups, allowing commonalities and differences across groups to become evident. Here, we focus on regeneration in the Spiralia, a group that includes several champions of animal regeneration, as well as many groups with more limited abilities. We review the phylogenetic distribution and developmental processes of regeneration in four major spiralian groups: annelids, nemerteans, platyhelminths, and molluscs. Although comparative data are still limited, this review highlights phylogenetic and developmental patterns that are emerging regarding regeneration in spiralians and identifies important avenues for future research.