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PubMed · 16012094

A new technique for identifying sequence heterochrony.

Jonathan E Jeffery·Olaf R P Bininda-Emonds·Michael I Coates·Michael K Richardson
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Abstract

Sequence heterochrony (changes in the order in which events occur) is a potentially important, but relatively poorly explored, mechanism for the evolution of development. In part, this is because of the inherent difficulties in inferring sequence heterochrony across species. The event-pairing method, developed independently by several workers in the mid-1990s, encodes sequences in a way that allows them to be examined in a phylogenetic framework, but the results can be difficult to interpret in terms of actual heterochronic changes. Here, we describe a new, parsimony-based method to interpret such results. For each branch of the tree, it identifies the least number of event movements (heterochronies) that will explain all the observed event-pair changes. It has the potential to find all alternative, equally parsimonious explanations, and generate a consensus, containing the movements that form part of every equally most parsimonious explanation. This new technique, which we call Parsimov, greatly increases the utility of the event-pair method for inferring instances of sequence heterochrony.

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AlgorithmsAnimalsClassificationData Interpretation, StatisticalMorphogenesisPhylogenyTime FactorsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

Jonathan E Jeffery, Olaf R P Bininda-Emonds, Michael I Coates, Michael K Richardson. 2005. A new technique for identifying sequence heterochrony.. https://doi.org/10.1080/10635150590923227

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