We are working on multiple annelid genomes to better understand genomic basis of regeneration. We are also interested in understanding how the polychaete Capitella teleta has maintained remarkable levels of genomic conservation (e.g., synteny, gene sequence, gene content), and the leech Helobdella robusta appears to have experienced much larger genomic evolutionary changes. When did these changes happen? How widespread are they? Are they responsible for making a leech a leech or did they define many other annelid lineages?