Metazoan cell lineages can be collapsed to a set of rules that is surprisingly simple, according to Ricardo Azevedo (University of Houston, Houston, TX), Armand Leroi (Imperial College, Ascot, UK), and colleagues. Decoding the biochemical basis of the rules should provide a complete recipe book for development.
Azevedo brought three influences to the study: his background in evolutionary biology; his adopted field of worm biology; and computer science from collaborators. When he joined Leroi's worm lab he “was immediately struck by the lineage data,” he says. “But there were more data to be extracted.”
As in phylogenetic trees, there were repeating patterns. A handful had been noted by others, but no systematic study had been undertaken. This is where a simple computer algorithm helped out.
“For any particular cell division we can find another that forms the same pattern,” Azevedo explains. “Then we collapse [those...
