Model of Algal Plastid Evolution
   
  Model for the origin of algal plastids. The three primary algal lineages (glaucophytes, chlorophytes, and rhodophytes) arose after a cyanobacterial (CB) primary endosymbiosis in their common ancestor. The green and red algae gave rise thereafter to most other algal lineages through secondary endosymbiosis. The dinoflagellate plastid may have arisen through a tertiary endosymbiosis involving a haptophyte. The plastid-based phylogenetic framework is shown in different colors, whereas the "host" tree is shown in black. Resolving all the unclarified nodes in the host tree (indicated with broken lines) and establishing the relationship between plastid and nuclear genome evolution remain important challenges for our lab and for endosymbiosis research in general. Photo not to be used without permission of D. Bhattacharya.