Figure 1

Relationship and divergence times of deuterostome and vertebrate species. This tree represents a survey of molecular and paleontological analyses of phylogeny and divergence times. Divergence times estimates are given in millions of years ago (MYA). The timing of genome duplication events from the first round (1R), second round (2R), and the teleost-specific third round (3R) are represented by rounded rectangles. The dotted line for the connection of the agnathan lineages represents the current uncertainty regarding their divergence relative to the second round of genome duplication.