Send to

Choose Destination
Development. 2002 Jul;129(13):3021-32.

The last common bilaterian ancestor.

Author information

Department of Paleobiology, National Museum of Natural History, Washington, D.C. 20560, USA.
Smithsonian Inst, Washington, DC
CA Inst Technol, Pasadena


Many regulatory genes appear to be utilized in at least superficially similar ways in the development of particular body parts in Drosophila and in chordates. These similarities have been widely interpreted as functional homologies, producing the conventional view of the last common protostome-deuterostome ancestor (PDA) as a complex organism that possessed some of the same body parts as modern bilaterians. Here we discuss an alternative view, in which the last common PDA had a less complex body plan than is frequently conceived. This reconstruction alters expectations for Neoproterozoic fossil remains that could illustrate the pathways of bilaterian evolution.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center