Modelling the covarion hypothesis of nucleotide substitution

  title={Modelling the covarion hypothesis of nucleotide substitution},
  author={Chris Tuffley and Mike Steel},
A “covarion” model for nucleotide substitution which allows sites to turn “on” and “off” with time was proposed 27 years ago by Fitch and Markowitz. It has been argued recently that evidence supports such models over later, alternative models which postulate a static distribution of rates across sites. However, in contrast to these latter well-studied models, little is known about the analytic properties of the former model. Here we analyse a covarion-style model and show (i) how to obtain the… CONTINUE READING