The last common bilaterian ancestor

Erwin, Douglas H.; Davidson, Eric H.

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NASA NTRS · 20040088270

The last common bilaterian ancestor

Erwin, Douglas H.·Davidson, Eric H.

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Abstract

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.

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Review NASA Discipline Exobiology Review, Tutorial NASA Discipline Evolutionary Biology Non-NASA Center Drosophila/physiology Fossils Chordata, Nonvertebrate/physiology Evolution Gene Expression Regulation, Developmental Animals Phylogeny Support, U.S. Gov't, Non-P.H.S Support, Non-U.S. Gov't Morphogenesis

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Erwin, Douglas H., Davidson, Eric H.. 2002-07-01. The last common bilaterian ancestor. https://ntrs.nasa.gov/citations/20040088270

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